We have made significant changes to this page of the site according to the comments . They are connected, first of all, with GOST 4835-2006, which establishes new types and sizes of wheel sets. We draw the attention of readers to the fact that according to this GOST, RU1 axles (with threads and castellated nuts) are no longer produced, and the wheel diameter along the rolling circle is not 950 mm, as it was before, but 957 mm.
Wheelsets are part of the chassis and are one of the critical elements of the car. They are designed to guide the movement of the car along the rail track and the perception of all loads transmitted from the car to the rails during their rotation. Working under difficult loading conditions, wheel sets must provide high reliability, since the safety of train traffic largely depends on them. Therefore, they are subject to special, increased requirements of the State Standard, Rules technical operation railways, Instructions for the inspection, repair and formation of wagon wheelsets, as well as others regulations in design, manufacture and maintenance. The design and technical condition of the wheelsets affect the smoothness of the ride, the magnitude of the forces arising from the interaction of the car and the track, and the resistance to movement.
Working in modern modes of operation of railways and extreme environmental conditions, the wheelset of the car must meet the following basic requirements: to have sufficient strength, while having a minimum unsprung mass in order to reduce the tare of the rolling stock and reduce the direct impact on the rail track and car elements when passing rail track irregularities; have some elasticity, providing a reduction in the noise level and mitigation of shocks that occur when the car moves along the track; together with the axleboxes, provide, possibly, less resistance during the movement of the car and, possibly, greater resistance to wear of elements subject to wear in operation.
Classification of wheel pairs. Improving their designs
The wheel pair (Fig. 1) consists of axle 1 and two wheels mounted on it 2 . Types, main dimensions and technical conditions for the manufacture of wagon wheelsets are determined by the State Standards, and the maintenance and repair of the "Rules for the technical operation of railways" (PTE) and "Instructions for the inspection, survey, repair and formation of wagon wheelsets TsV / 3429", and as well as other regulatory documents in the design, manufacture and maintenance. The design and technical condition of the wheelsets affect the smoothness of the ride, the magnitude of the forces arising from the interaction of the car and the track, and the resistance to movement.
The type of wheelset is determined by the type of axle and the diameter of the wheels(Table 1). According to GOST 4835-2006, five types of wheelsets are installed with axles of types RU1Sh and RV2Sh and wheels with a diameter of 957 mm along the tread circle, depending on the type of car and the maximum design static load from the wheelset on the rails (table 1).
Table 1 Types of wheel pairs of wagons
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Wheelset type |
Wagon type |
Car design speed, km/h |
Maximum calculated static load from the wheelset on the rails, kN (tf) |
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Cargo |
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Passenger |
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Non-motorized electric trains |
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Non-motorized diesel trains |
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Cargo |
An example of a symbol for a wheel pair for a freight car with a RU1SH type axle and wheels with a diameter of 957 mm with axleboxes:
Wheel set RU1Sh-957-G GOST 4835-2006
The same, without axle boxes:
Wheel set RU1Sh-957 without axle boxes GOST 4835-2006
At present, RU1 axles with end fastening with an M110 nut are excluded from GOST 4835-2006, and most plants have stopped producing axles. of this type. Wheel sets RU1-950 and RU1SH-950 can still be found in operation.
Neck diameters 3 , (Fig. 1), sub-hub 5 and middle 6 axle parts are determined based on the calculated load. Pre-incisor part 4 is a stage of transition from the neck to the hub part of the axle and serves to install the sealing devices of the box body. On hub parts 5 wheels firmly attached 2 . On necks 3 bearings are placed.
Rice. 1. Wheelset and axle journal shape: 1 - axis; 2 - wheel; 3 - neck; 4 - pre-hub part; 5 - substand part; 6 - middle part; 7 - threaded part
Wheelsets with axles intended for operation with roller bearings are distinguished from each other by the design of the end fastening of the inner rings roller bearings on the neck:
with a threaded part 7 for screwing the castellated nut (axis RU1);
with the help of an attachment washer, for which purpose threaded holes are made at the ends for the fastening bolts (axis РУ1Ш Fig. 1). This fastening is made in two versions: three or four bolts.
Much attention was paid to the strength and reliability of wheel sets when creating the first wagons. The normal axle until 1892 had the diameters of the necks, hub and middle parts, respectively, 100, 135 and 126 mm. In connection with the increase in the carrying capacity and tare of wagons, as well as the speed of trains, the loads acting on the wheelsets increased, which required strengthening of their elements. As a result, the diameters of the axles increased, the design of the wheels improved, and the strength of their fit on the axle increased.
In pre-revolutionary Russia, wheel sets were equipped with composite (shroud) wheels, consisting of a wheel center, a bandage and elements reinforcing it. Until 1892, wheels were used, the centers of which were wooden (Fig. 2) (Menzel's wheels). They were made from hard wood. A wooden disk was placed in the wheel center 2 , consisting of 16 teak sectors. He was between the bandage 1 and hub 3 , was fastened to them with rings 4 and 5 bolted 6 .
Fig.2 Wheel with wooden center
As noted, in those days, such wheels had a silent and relatively quiet ride, and softened vertical shocks. However, due to the shrinkage of the tree during operation, the bolts weakened, which violated the safety of train traffic and led to the need for constant monitoring of the condition of the fastening.
Therefore, wheels with wooden centers (Menzel wheels) were removed from service. Until 1900, forged centers became widespread, then cast spoke, steel and cast iron discs. In 1948, the production of cast-iron centers was discontinued due to the large mass, low strength and frequent damage during the formation of wheelsets. The production of spoke centers also stopped due to the uneven rigidity of the rim and the weakening of the connection with the bandage, air turbulence. The swirl of air caused sand to get on the rubbing surfaces of the chassis and increased wear and tear of the metal.
In 1931, a transition was made from shroud wheels to more advanced tireless ones, which was completed in the 70s. In 1953, the production of cast-iron wheels was also discontinued, as they often had dents, shells, and spalls that threatened the safety of train traffic and shortened their service life. Cast steel have proved to be more reliable in operation. Since 1935, the production of solid-rolled wheels has been organized, which have significant advantages over cast ones. Over the years, solid-rolled wheels have improved, and they have become widespread.
For the safe movement of the car along the rail track, wheels 2 are firmly fixed to axle 1 (Fig. 3) with strictly defined dimensions. The distance between the inner edges of the wheels2s is: for new wheelsets intended for cars circulating at speeds up to 120 km / h - (1440 ± 3), over 120, but not more than 160 km / h - (1440) mm. Nominal tread distance2l equal to 1580 mm, and between the centers of the necks2b - 2036 mm.
Fig.3. The main dimensions of the wheelset
To avoid uneven load transfer to wheels and rails size differencek from the end of the axle to the inner edge of the rim, no more than 3 mm is allowed. Wheels mounted on the same axle must not have diameter differenceD more than 1 mm, which prevents one-sided wear of the ridges and does not allow an increase in resistance to movement. In order to reduce inertial forces, the wheel pairs of high-speed cars are subjected to dynamic balancing: for speeds of 140...160 km/h, an imbalance of no more than 6 Nm is allowed; for speeds of 160...200 km/h - no more than 3 Nm. The nominal width of the wheel rim for all types of wheelsets is 130 mm.
In addition to wheelsets manufactured in accordance with GOST 4835-80, they also supply structures made according to special drawings and specifications for industrial transport cars, cars of electric and diesel trains, as well as with wheels that are sliding on the axle for operation on roads with various gauge, etc. In wagons equipped with disc brakes, on the axle 1 (Fig. 4), except for two wheels 2 , firmly reinforced discs 3.
Fig.4 Wheel pair with brake discs (3)
The wheelset of the motor car of an electric train (Fig. 5) consists of an axle 5 and two bandage wheels 6 with cast-spoke wheel centers 2 and tires 1. One wheel center has an elongated flange 7, to which the gear wheel flange 3 of the gearbox is attached with precision bolts. The reducer is mounted on the bearing-reducer unit 4. The wheel pairs of industrial transport cars, designed for operation with increased loads, have increased diameters, in particular, the diameter of the necks is 180 mm.
Rice. Fig. 5. Wheel set of a motor car of an electric train: 1 - bandage; 2 - spoke center; 3 - gear; 4 - bearing-reducer assembly; 5 - axis; 6 - shroud wheel; 7 - flange
Wheel sets with sliding wheels on the axle have a more complex structure. In 1957, at the Bryansk Machine-Building Plant, a wheel pair was created with wheels sliding on the axle (Fig. 6). The movement of the wheels from one position to another occurs automatically when the car moves along a special transfer stand, connected at one end to the 1520 mm gauge, and the other end to the 1435 mm gauge. The sliding wheelset consists of an axle 2 along which the wheels can move 1 at the transition of a wagon from a track of one gauge to a track of another gauge.
Rice. 6. Wheel set with wheels sliding on the axle for rolling stock circulating on 1520 and 1435 mm gauge roads without changing running gear: 1 - wheel; 2 - axis; 3 - sleeve; 4 - locking ring; 5 - drum; 6 - buffer; 7 - lid; 8 - spring
To ensure sliding between the wheel hub 1 and the hub part of the axle 2 kapron bushing installed 3 . On the outer surface of the hub there are two annular grooves for fixing the wheel on the axle by means of sectors 9 . Do the sectors enter one groove when the wheel is in a track of 1520 mm, and the second? in a track of 1435 mm. This position of the sectors is fixed by the drum 5 , reinforced on the axle by means of a shrink fit. To prevent spontaneous exit of sectors from the annular grooves of the hub, a lock ring is provided. 4 bolted to buffer 6 . Springs are located inside the buffer 8 leaning on the lid 7 and pressing the buffer and the lock ring to the middle of the axis. The rotation of the wheel on the axle is prevented by the gearing of the drum and the wheel hub.
The sliding wheel pair is actuated as follows. When the car passes through the transfer stand, the buffer is squeezed out with a special stop 6 , resulting in lock rings 4 move towards the wheels and stop holding the sectors 9 in the recesses of the hub. Then the emphasis of the stand, pressing the wheels 1 , moves them along the axis 2 to the required position. At the beginning of this movement, the wheels squeeze sectors 9 from the annular grooves, at the end of the movement of the wheels, the sectors are opposite the second grooves. At the same time, they are released from buffer pressing 6 and under the action of springs 8 come back with lock rings 4 to the starting position. While the rings 4 click on sectors 9 , as a result of which the sectors enter the second grooves, fixing the wheels in the changed position.
One of the design options for a wheelset with sliding wheels was developed by specialists from Uralvagonzavod and VNIIZhT.
Structures with sliding wheels differ from conventional wheelsets in a more complex device, increased weight and manufacturing cost. However, technical and economic calculations show that during the transportation of certain goods, sliding wheelsets, despite the above disadvantages, including additional costs for repairs and maintenance, can reduce capital investments and operating costs compared to the costs necessary for organizing and performing reloading operations at border stations. Non-reloading communication also ensures the reduction of cargo losses and the acceleration of their delivery to the consumer, which is important especially for perishable goods.
Wheel sets of narrow-gauge wagons are of great diversity. For example, there were 42 types of wheelsets of 750 mm gauge, of which 30 had collars at the ends of the necks and 12 without collars, 14 sizes according to the diameter of the wheels - from 450 to 650 mm. The wheels were bandage with cast-iron or steel (disc or spoke) wheel centers, as well as bandless - cast-iron and steel solid-rolled. On fig. 7 shows a wheel set without collars on the axle journals, used in cars of narrow gauge railways, which were equipped with axle boxes that did not have bearings. on axle 1 on the left is a section of a tire wheel with a disk center 2 on which the bandage is firmly put on 4 , reinforced against shear by a safety ring 3 , and on the right is a tireless wheel 5 . In 1955, the Main Directorate of the Carriage Facilities of the Ministry of Railways carried out the unification of the wheelsets of 750 mm gauge cars, which sharply reduced their diversity.
Rice. Fig. 7. Wheel pair without collars on the neck of the axle of narrow-gauge wagons of 750 mm gauge: 1 - axle; 2 - disk center; 3 - safety ring; 4 - bandage; 5 - solid-rolled wheel
The wagon axle (Fig. 1) is an integral part of the wheelset and is a steel bar with a round, variable cross-section along the length. On the hub parts of the 3rd axle there are wheels fixed rigidly or movably, and bearings are placed on the necks 1. Carriage axles differ in size, determined depending on the given load; the shape of the axle neck in accordance with the type of bearing used - for rolling bearings and plain bearings; round cross-sectional shape - solid or hollow; the way of end fastening of rolling bearings on the axle neck - with a castellated nut or washer.
Rice. 1. Types of wagon axles: 1 - neck; 2 - pre-hub part; 3 - hub part; 4 - middle part
In addition, axles are classified according to material and manufacturing technology. Between necks 1i hub parts 3 are pre-hub parts 2, which serve to accommodate the parts of the rear sealing devices of the axle boxes, as well as to reduce the stress concentration in the transition sections from the hub parts to the axle journals. In places where diameters change, to reduce stress concentration, there are smooth mates - fillets, made with certain radii: from the neck 1 - to the sub-hub 2, from the pre-hub - to the sub-hub 3 and from the middle 4 - to the sub-hub. Reducing the concentration of stresses caused by the fit of the inner ring of the roller bearing is provided by a relief groove located at the beginning of the rear fillet of the axle journal (Fig. 8, G). Axles for rolling bearings at the ends of the necks have a threaded part To(fig.1, a) for screwing a castellated nut, at the end there is a groove with two threaded holes for setting and fastening with two bolts of the locking bar.
In wagon axles with mounting of rolling bearings, threaded holes for bolts are made at the ends of the necks with the help of an attachment washer (Fig. 1, b) in two versions: with the help of three or four bolts. Center holes are provided at the ends of all types of axles (Fig. 1, d, e), serving to install and secure the axle or wheelset in the centers when processing on lathe. The shape and dimensions of the center holes are standardized. Axles of wheel sets equipped with a disc brake, as well as axles on which the undercarriage generator drive is provided, have seating surfaces for installing brake discs or gearbox parts. The main dimensions and permissible loads for standard types of axles of wide gauge cars, except for cars of electric and diesel trains, are given in Table. 2.
Roller bearings with an outer diameter of 250 mm are installed on the journals of the axles RU1 and RU1SH.
For all types of axles, the distances between the centers of application of the load to the journals are the same and amount to 2036 mm. For freight cars with increased loads from the wheelset on the rails up to 245 kN, a reinforced axle with increased diameters is provided.
(with amendments and additions approved by the order of the Ministry of Railways of Russia dated 23.08.2000 No. K-2273u)
1. INTRODUCTION………………………………………………………………………………………………….. 3 2. GENERAL PROVISIONS ……… ………………………………………………………………………… 3 3. TECHNICAL CONTENT AND BASIC REQUIREMENTS FOR THE WHEELS IN OPERATION ………………… . 5 4. TYPES, TERMS AND PROCEDURE OF SURVEY OF WHEELS9 5. FAULTS OF WHEELS AND WAYS TO ELIMINATE THEM …………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………….. 12 12………………………………………. GENERAL REQUIREMENTS……………………………………………………………………………………………………. 20 6.2. PROCESSING OF NEW AND OLD YEAR AXES. ………………………………………………………………….. 21 6.3. PROCESSING OF NEW AND OLD CENTERS, SOLID-ROLLED AND GEARS…… 23 6.4. REPAIR OF GEARS. ………………………………………………………………………………………….. 25 6.5. BORING OF NEW AND OLD BANDAGES. ……………………………………………………………. 26 6.6. NOZZLE (CHANGE) OF BANDAGES. ……………………………………………………………………………………… 27 6.7. PRESS WORKS …………………………………………………………………………………………………… 29 6.8. THERMAL METHOD OF FORMING WHEELS…………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………. The turn of the bandages and rims of whole -roll wheels in the profile ……………………… 36 6.10. ФОРМИРОВАНИЕ КОЛЕСНЫХ ПАР………………………………………………………………………………… 44 7. ПРОВЕРКА, ПРИЕМКА И ИСКЛЮЧЕНИЕ ИЗ ИНВЕНТАРЯ КОЛЕСНЫХ ПАР 45 8. МАРКИРОВАНИЕ AND STAMPING OF WHEELS AND THEIR ELEMENTS … 46 THEIR ELEMENTS …………………………………………………………………………………………………… 53 11. SAFETY REQUIREMENTS AND ENVIRONMENTAL MEASURES ……… ……………………………………………………………………………………. 54 12. METROLOGICAL PROVISION…………………………………………………….. 54 APPENDIX 1………………………………………………………… …………………………………………………………… 56 APPENDIX 2………………………………………………………………… …………………………………………………… 59 APPENDIX 3………………………………………………………………………… …………………………………………… 59 APPENDIX 4………………………………………………………………………………… …………………………………… 60 APPENDIX 5………………………………………………………………………………………… …………………………… 61 APPENDIX 6……………………………………………………………………………………………… …………………… 66 APPENDIX 7……………………………………………………………………………………………………… …………… 68 APPENDIX 8……………………………………………………………………………………………………………… …… 70 APPENDIX 9…………………………………………………………………………………………………………………… 74 APPENDIX 10…………………………………………………………………………………………………………………. 76 APPENDIX 11………………………………………………………………………………………………………………. 78 APPENDIX 12………………………………………………………………………………………………………………. 78 APPENDIX 13………………………………………………………………………………………………………………. 78
1. INTRODUCTION
1.1. This Instruction applies to wheelsets of all types of locomotives and multi-unit rolling stock (MVPS) of 1520 mm gauge. Locomotives and MVPS are hereinafter referred to as traction rolling stock (TPS).
1.2. The instruction establishes the procedure, terms, norms and requirements that must be met by wheel sets during their formation, repair (survey) and technical maintenance.
1.3. All newly issued operational and repair documentation for wheelsets must strictly comply with this Instruction and GOST 11018, and the current documentation must be brought in accordance with them.
1.4. The requirements of this Instruction are obligatory in the manufacture, repair, maintenance and operation of wheel sets.
(As amended by the instruction of the Ministry of Railways of Russia dated 23.08.2000 No. K-2273u)
1.5. Instruction dated 31.12.85. No. TsT / 4351 is valid in terms of the manufacture and repair of wheel pairs of steam locomotives.
2. GENERAL PROVISIONS
2.1. In accordance with the Rules for the Technical Operation of Railways of the Russian Federation (hereinafter PTE), each wheel pair must meet the requirements of this Instruction. Wheel sets of TRS with rolling bearings must also meet the requirements of the current Instructions for the maintenance and repair of units with rolling bearings of locomotives and multiple unit rolling stock.
The wheelsets of the TPS operating at speeds over 140 km/h must, in addition, meet the requirements of the current Instructions for the maintenance and operation of structures, rolling stock devices and the organization of traffic in the areas of circulation of high-speed passenger trains.
Manufacture and repair of driven gears of traction gearboxes with elastic rubber-metal elements, assemblies and parts of wheel pair drives with support-frame and support-axial suspension of traction motors must be carried out in accordance with the requirements of the relevant existing drawings, repair rules, technological instructions, repair manuals and GOST 11018.
Compliance with the requirements of the specified technical documentation is mandatory for all employees associated with the formation, examination, repair and operation of wheel sets.
2.2. Each wheel pair must have clearly marked marks on the axle indicating the time and place of formation, complete examination and a stamp confirming its acceptance during formation and complete examination. Elements of the wheelset must have signs and stamps established by the relevant standards, specifications and this Instruction. After repair in the CIS countries and Latvia, the operation of wheel sets and their individual elements without the “Hammer and Sickle” stamp is allowed, provided that the other prescribed stamps are present (section 8).
2.3. Wheelsets must be subject to inspection under the TPS, ordinary and complete survey, in accordance with the procedure established by this Instruction.
2.4. A complete survey should be carried out at factories and in locomotive depots that have a permit from the Ministry of Railways and a mandatory minimum of equipment, fixtures, measuring and control instruments in accordance with Annexes 1 and 2.
2.5. Responsibility for the maintenance of tools and measuring instruments in good condition, as well as for the timely verification (calibration) of measuring instruments, rests with the head of the wheel shop or the foreman who manages the repair and formation of wheel pairs.
Control over the organization and timeliness of verification (calibration) of measuring instruments is carried out by:
at the factory - head of department technical control;
in the depot - chief engineer or deputy head of the repair depot.
(As amended by the instruction of the Ministry of Railways of Russia dated 23.08.2000 No. K-2273u)
2.6. The condition of equipment, fixtures and tools for the repair (examination) of wheel sets, as well as compliance with the requirements of this Instruction at plants and depots, must be annually checked by commissions chaired by the chief engineer (or his deputy at the plant) with the participation of the Quality Control Department and locomotive inspectors ( acceptance inspectors at the factory).
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Foreword
The goals, basic principles and basic procedure for carrying out work on interstate standardization are established by GOST 1.0-92 “Interstate standardization system. Basic Provisions” and GOST 1.2-2009 “Interstate Standardization System. Interstate standards, rules and recommendations for interstate standardization. Rules for the development, adoption, application, updating and cancellation "
About the standard
1 DESIGNED BY OPEN joint stock company"Scientific-Research and Design-Technological Institute of Rolling Stock" (JSC "VNIKTI")
2 INTRODUCED by the Federal Agency for Technical Regulation and Metrology
3 ADOPTED by the Interstate Council for Standardization, Metrology and Certification (Minutes No. 40 dated November 29, 2011)
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Short name of the country according to MK (ISO 3166) 004-97 |
MK country code (ISO 3166) 004-97 |
Abbreviated name of the national standards body |
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Azerbaijan |
Azstandard |
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Ministry of Economy of the Republic of Armenia |
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Belarus |
State Standard of the Republic of Belarus |
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Kazakhstan |
State Standard of the Republic of Kazakhstan |
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Kyrgyzstan |
Kyrgyzstandart |
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Moldova-Standard |
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Russian Federation |
Rosstandart |
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Gospotrebstandart of Ukraine |
4. This standard has been developed taking into account the main provisions of the international standard ISO 1005-7: 1982 “Railway rolling stock. Part 7. Wheel sets for rolling stock. Quality requirements" (ISO 1005-7:1982 "Railway rolling stock materia - Part 7: Wheelsets for tractive and trailing stock - Quality requirements", NEQ)
5. By order of the Federal Agency for Technical Regulation and Metrology dated March 5, 2012 No. 14-st, the interstate standard GOST 11018-2011 was put into effect as the national standard of the Russian Federation from January 1, 2013.
For the Russian Federation, this standard fully implements the requirements of the technical regulation "On the safety of railway rolling stock" in relation to the object of technical regulation - wheel sets of locomotives and multiple unit rolling stock, as well as the requirements of the technical regulation "On the safety of high-speed railway transport" in relation to the object of technical regulation - wheel pairs of high-speed railway rolling stock:
4.3.2 - 4.3.13, 4.3.15, 4.3.17, 5.2.6, 5.3.4 - 5.3.7, 5.3.7.1 - 5.3.7.9 contain the minimum required safety requirements;
Subsection 6.5 establishes the rules for sampling for conformity assessment;
7.1.1, 7.1.2, 7.1.4, 7.1.5, 7.1.8, 7.1.10, 7.1.12 - 7.2, 7.3.4 specify the methods of verification necessary requirements security.
Information about changes to this standard is published in the annually published information index "National Standards", and the text of changes and amendments - in monthly published information signs "National Standards". In case of revision (replacement) or cancellation of this standard, a corresponding notice will be published in the monthly published information index "National Standards". Relevant information, notification and texts are also posted in the public information system- on the official website of the Federal Agency for Technical Regulation and Metrology on the Internet
INTERSTATE STANDARD
Introduction date- 2013-01-01
1 area of use
This standard establishes the requirements for drive wheelsets of locomotives (tenders), motor cars of multiple unit rolling stock (traction rolling stock) of 1520 mm gauge railways with UHL climate modification according to GOST 15150.
2 Normative references
This standard uses normative references to the following interstate standards:
* On the territory of the Russian Federation, GOST R 52366-2005 applies (hereinafter).
GOST R 51175-98 (hereinafter).
Wheel rolled and stamped centers and other parts of the wheelset - according to the regulatory document (RD), approved in the prescribed manner.
A
B C
D- the diameter of the wheels in the circle of skating;
E- tolerance of the radial runout of the wheel tread;
G
B
Figure 1 - Wheel pair with one gear on the axle
A- the distance between the inner ends (faces) of the tires (rims) of the wheels;
B- the width of the bandage (rim) of the wheel; C- the distance between the thrust end of the pre-hub part of the axle
and the inner end of the tire (rim) of the wheel; D- the diameter of the wheels in the circle of skating; E- admission
radial runout of the wheel tread; G- tolerance of the end runout of the inner end of the bandage
(rim) wheels; B- geometric axis of the wheelset; To- axis symmetry plane;
T - size symmetry tolerance BUT relative to the plane To(in diametric terms)
Figure 2 - Wheel pair with two gear wheels on elongated wheel hubs
A- the distance between the inner ends (faces) of the tires (rims) of the wheels;
B- the width of the bandage (rim) of the wheel; C- the distance between the thrust end of the pre-hub part of the axle
and the inner end of the tire (rim) of the wheel; D- diameter of the wheel in a circle of skating;
E- tolerance of the radial runout of the wheel tread;
G- tolerance of the end runout of the inner end of the tire (rim) of the wheel;
B- geometric axis of the wheelset
Figure 3 - Wheelset with axle gear and disc brakes
4.2.1 Axle requirements
4.2.1.1 Roughness parameter Ra* axle surfaces should be:
* Here and below, instead of the roughness parameter, Ra apply the appropriate setting Rz according to GOST 2789.
Necks for rolling bearings and wheel hubs - no more than 1.25 microns;
Necks for axial plain bearings for TPS with design speed v K:
no more than 100 km/h - no more than 1.25 microns;
more than 100 km / h - no more than 0.63 microns;
The middle part - no more than 2.5 microns;
Hub parts for gear wheels and brake discs - no more than 1.25 microns;
for thrust bearings of rolling and sliding - no more than 2.5 microns;
non-working - no more than 6.3 microns;
Galteley:
bearing journals - no more than 1.25 microns;
hub journals - no more than 2.5 microns.
For hollow axes, the roughness parameter Ra the surface of the central hole should be - no more than 6.3 microns.
4.2.1.2 Variability tolerance of the diameter ** of the axis in transverse and longitudinal sections must be, mm, not more than:
** Here and below, instead of the variability of the diameter in the cross section, it is allowed to measure the deviation from roundness, instead of the variability of the diameter in the longitudinal section, to measure the profile of the longitudinal section. The tolerance of roundness and profile of the longitudinal section should be 0.5 of the tolerance value for the variation of the diameter in the transverse or longitudinal section.
0.015 - for journals for rolling bearings;
0.05 - for journals for axial plain bearings;
0.05 - for wheel hubs, in the case of a conical shape, the larger diameter should face the middle of the axle;
0.05 - for hub parts for gear wheels or for hubs of gear rims and brake discs;
0.03 - for pre-wheel parts under thrust rings of axle bearings.
4.2.1.3 Radial run-out tolerance when checking in the centers of the axle journals for rolling and plain bearings, wheel hubs, brake discs and gears shall be no more than 0.05 mm.
4.2.1.4 The runout tolerance of the thrust ends of the pre-hub parts of the axle when checking in centers of more than 0.05 mm is not allowed.
4.2.1.5 The axle must be subjected to ultrasonic testing for internal defects and sounding according to GOST 20415 and magnetic testing of surface defects according to GOST 21105.
Requirements for permissible and impermissible defects detected by ultrasonic and magnetic testing, and requirements for the soundness of axes - in accordance with GOST 31334.
4.2.1.6 The surfaces of the axle journals, pre-hub, hub and middle parts, as well as the fillets of the transition from one part of the axle to another, must be hardened by rolling with rollers in accordance with GOST 31334.
4.2.2 Wheel and wheel center requirements
4.2.2.1 The difference in the hardness values of solid wheel rims or composite wheel tires for one wheel pair of more than 24 HB units is not allowed.
4.2.2.2 The difference in width of the tire (rim) of the wheel (see Figures 1, 2 and 3, size B) is not allowed to exceed 3 mm.
4.2.2.3 Roughness parameter Ra landing surfaces must be:
Wheel hub or wheel center bores:
with the thermal method of formation - no more than 2.5 microns;
with the press method of formation - no more than 5 microns;
The outer surface of the wheel center for the fit of the bandage - no more than 5 microns;
The inner landing surface of the bandage - no more than 5 microns;
Elongated hub for gear wheel fit - no more than 2.5 microns.
4.2.2.4 Variation in diameter is not allowed:
For wheel hub or wheel center bore:
more than 0.05 mm - in cross section;
more than 0.05 mm - in the longitudinal section, in the case of a conical shape, the larger diameter should face the inner end of the hub;
For the outer surface of the wheel center for the fit of the tire:
0.2 - in cross section;
0.1 - in the longitudinal section, in the case of tapering, the direction of the taper of the outer surface of the wheel center must coincide with the direction of the taper of the inner seating surface of the tire, and the difference in the tolerance values for the variability of the diameter of the seating surfaces in the longitudinal section must be no more than 0.05 mm.
4.2.2.5 The upper and lower limit deviations from the nominal value of the diameter of the pairing of the axle and wheel hub (wheel center) by more than plus 2 and minus 1 mm, respectively, are not allowed. The difference in the thickness of the wheel hub (wheel center) at the ends, measured in the radial direction, except for the elongated part of the hub, is not more than 5 mm along the perimeter of the circle.
4.2.2.6 On a wheel center with an elongated hub for fitting a gear wheel, the wheel center hub hole is bored after the gear wheel (composite gear hub) is seated relative to the axis of the pitch circle of the gear wheel, while the alignment tolerance of the hole axis of the hub of the wheel center and the pitch circle of the gear wheel - no more than 0.15 mm.
4.2.2.7 The locations of the holes in the disk part of the wheel for fastening the brake disks shall be located taking into account the minimization of stresses from the action of operational loads.
4.2.2.8 On the inner seating surface of the bandage with a width of up to 10 mm, located at the thrust shoulder and at the undercut for the bandage ring, blackings are not allowed. On the rest of this surface, no more than two drafts with a total area of not more than 16 cm 2 are allowed with a maximum draft length of not more than 40 mm.
4.2.2.9 The junction radii of the profile elements of the tread undercut for the tread ring shall be at least 2.5 mm, the junction radius of the seating surface and the thrust collar shall be at least 1.5 mm. Roughness parameter Ra surfaces of the recess under the shroud ring and under the thrust collar should be no more than 10 microns. On the edges of the undercut for the shroud ring, facing the inner seating surface of the shroud and the thrust collar, there must be chamfers of 1.5 mm in size at an angle of 45°. It is allowed to round edges with a radius of 2 mm instead of chamfers.
4.2.2.10 Tolerance of variability of the diameter of the seating surface of the bandage in the cross section should be no more than 0.2 mm, in the longitudinal section - no more than 0.1 mm. In the case of taper, the direction of the taper shall comply with the requirements for the mating surface of the wheel center according to 4.2.2.4.
4.2.2.11 The upper and lower deviations from the nominal value of the tire and wheel center mating diameter by more than plus 3 and minus 1.5 mm, respectively, are not allowed.
4.2.2.12 Cast wheel centers and solid-rolled wheels shall be subjected to ultrasonic testing in accordance with GOST 4491 and GOST 10791, respectively. Rolled, stamped and forged wheel centers must be subjected to ultrasonic testing in accordance with approved regulatory documentation.
By agreement with the consumer, it is allowed to control surface defects in rolled and stamped wheel centers, cast wheel centers, solid wheels using magnetic particle or acoustic methods.
4.2.2.13 The bandage must be subjected to ultrasonic testing in accordance with GOST 398, as well as to magnetic testing for the absence of defects (longitudinal and transverse cracks, hairline, captivity, delamination, etc.) on the inner seating surface.
4.2.2.14 Solid wheels and wheel centers of locomotives with a design speed over 100 to 160 km/h (up to 130 km/h - for MVPS wheel sets) shall be statically balanced, except for wheel centers for wheel sets subjected to dynamic balancing. The residual unbalance of the solid wheel and the wheel center must be no more than 12.5 kg cm. The location of the unbalanced mass must be marked on the wheel rim or wheel center by marking the number "0" with a height of 8 to 10 mm.
4.2.2.15 Landing of the bandage on the wheel center is carried out by the thermal method with an interference fit from 1.2 · 10 -3 to 1.6 · 10 -3 of the wheel center rim diameter. The shrinkage of the wheel center rim due to plastic deformation after assembly should be no more than 20% of the interference determined before forming.
4.2.2.16 The temperature of the tire before fitting onto the wheel center rim shall be between 220 °C and 270 °C. In the process of heating, it is necessary to record on the storage medium a graph of the change in temperature (heating diagram) of the bandage over time, and also to ensure automatic shutdown of the heater when the maximum allowable temperature is reached.
4.2.2.17 The shroud ring is inserted into the groove of the shroud with the thickened side at a shroud temperature of at least 200 °C and the clamping collar of the shroud is finally crimped with a force from 44 10 4 to 49 10 4 N (from 45 to 50 tf) at a temperature of at least 100 °C C. After compression of the clamping shoulder, the retaining ring must be tightly clamped in the groove. A gap between the ends of the shroud ring is allowed no more than 2 mm.
4.2.2.18 The clamping shoulder of the tire after the end of the compression must be machined to a diameter corresponding to the outer (fitting) diameter of the wheel center rim with maximum deviations of ±0.2 mm, at a length of (7 ± 1) mm from the inner end of the tire, with traces of processing on the bandage ring are not allowed.
4.2.2.19 To control the absence of rotation of the tire on the wheel center during operation, after landing the tire on the outer ends of the tire and the rim of the wheel center on one straight line along the radius of the composite wheel, control marks are applied. Control marks in the form of four to five cores with a depth of 1.5 to 2.0 mm with equal intervals between cores of at least 5 mm are applied no closer than 10 and no further than 45 mm from the inner diameter of the edge of the bandage thrust collar. A reference mark on the rim of the wheel center in the form of a groove with a depth of 0.5 to 1.0 mm and a length of 10 to 20 mm is applied with a blunt tool.
To control the minimum thickness of the rim of a solid wheel, an annular groove in the form of a groove 6 +1 mm wide and 2 +1 mm deep should be applied on the outer end of the rim in accordance with Figure 4.
D- limiting diameter of a wheel with a worn rim
Figure 4 - Annular groove
4.2.2.20 On the control marks apply control strips with a width of 30 to 40 mm:
On the bandage with red enamel for the entire thickness of the bandage;
On the rim of the wheel center - white (yellow) color.
4.2.3 Gear requirements (solid or composite)
4.2.3.1 Roughness parameter Ra the surface of the hole of the gear wheel or the hub of the compound gear before landing on the axle or the elongated hub of the wheel center must be, microns, not more than:
2.5 - with the thermal method;
5 - with the press method.
4.2.3.2 Tolerance of variability in the diameter of the hole of the gear or the hub of the composite gear in the transverse and longitudinal sections should be no more than 0.05 mm. In the case of taper, the direction of the taper must match the direction of the taper of the seating surface of the axle or extended wheel center hub.
4.2.3.3 The teeth of the gear wheel (crown) must be subjected to magnetic testing for the absence of surface defects in accordance with GOST 30803.
4.2.3.4 At the request of the customer, the gear wheels of wheel sets of locomotives with a design speed of more than 100 to 160 km/h (up to 130 km/h - for wheel sets of MVPS) must be subjected to static balancing. Residual unbalance should be no more than 12.5 kg cm. The location of the unbalanced mass must be marked with a marking - the number "0" with a height of 8 to 10 mm.
4.3 Wheel set requirements
4.3.1 Nominal basic dimensions of the wheelset (see figures 1, 2, 3):
A= 1440 mm;
B= 140 mm - for locomotives ( B= 150 mm - for bandages without a comb);
B= 130 mm - for MVPS;
C- according to technical documentation;
D- for:
Composite wheels of locomotives - according to GOST 3225;
Solid-rolled wheels MVPS - according to specifications or drawings;
4.3.2 Profile parameters of solid wheel rims and wheel tires according to:
Figure 5 - for wheel sets of locomotives with a design speed of up to 200 km/h;
Figure 6 - for MVPS wheelsets with design speed up to 130 km/h.
Figure 5 - Profile of the rim of a solid wheel or bandage of a prefabricated wheel of locomotives
Figure 6 - Profile of the rim of a solid wheel or bandage of a prefabricated wheel of MVPS wheel sets
It is allowed by agreement between the manufacturer, the customer and the owner of the infrastructure * the use of the profile of tires (rims) of wheels with other parameters (including wheels without a ridge), taking into account that the permissible impact on the track is not exceeded.
* In the Russian Federation, the infrastructure owner is determined federal law in the field of rail transport.
For locomotives and MVPS with a design speed up to 200 km/h inclusive, it is not allowed to increase the value of the nominal width of the rim of a solid wheel or a combined wheel rim in a wheel pair (see Figures 1, 2 and 3, size B) by more than 3 mm, and reduce - more than 2 and 1 mm, respectively; for TPS wheelsets with a design speed over 200 km/h - ±1 mm.
Deviations of other sizes - according to the 14th grade (GOST 25346).
4.3.3 Permissible deviation from the nominal value of the diameter in the rolling circle:
Tires of wheel pairs of locomotives in accordance with GOST 3225;
Tires of MVPS wheelsets and tenders in accordance with GOST 5000.
For TRS with a design speed of not more than 200 km/h, the difference in wheel diameters in the plane of the rolling circle for one wheel pair should be no more than 0.5 mm.
For wheel pairs of TRS with a design speed of over 200 km/h, the difference in wheel diameters in the plane of the rolling circle for one wheel pair of more than 0.3 mm is not allowed.
4.3.4 Radial run-out tolerance of wheel tread (see figures 1, 2 and 3, value E) when checking in the centers (axis B) for the TPS should not be, mm, more than:
0.5 - at v to no more than 120 km / h;
0.3 - at v to over 120 km/h.
4.3.5 The distance between the inner ends of the tires (rims) of the wheels (size A) for TPS should be:
mm - at v to no more than 120 km / h;
(1440 ± 1) mm - at v to over 120 km/h.
4.3.6 Tolerance of the end runout of the inner ends of the tires (rims) of the wheels ( G) when checking in centers (axis B) for TPS should not exceed, mm:
1.0 - at v to no more than 120 km / h;
0.8 - at v to over 120 km/h up to 160 km/h inclusive;
0.5 - at v to over 160 km / h up to 200 km / h inclusive;
0.3 - at v to over 200 km/h.
4.3.7 Roughness parameter Ra surfaces of the tread profile and wheel flanges of wheel pairs of TRS with a design speed of not more than 200 km / h should not be more than 10 microns, the inner ends of the tires (rims) of the wheels - more than 20 microns.
For wheel sets of TRS with a design speed of over 200 km/h, the roughness parameter Ra surfaces of the tread profile, wheel flanges, the inner surface of the tires (rims) of the wheels, as well as the disk part and the wheel hub should not be more than 6.3 microns.
4.3.8 On the inner ends of the wheel rims of wheel sets of TRS with a design speed of not more than 120 km/h, dispersed blacks with a depth of not more than 1 mm, not extending to the radius of mating with the wheel flange, are allowed. The total area of black holes is not more than 50 cm 2 .
4.3.9 The difference in distances from the inner ends of the tires (rims) of the wheels to the thrust ends of the pre-hub parts of the axle (see Figures 1, 2 and 3, the difference in sizes FROM) for one wheel pair should not exceed 2.0 mm at a design speed up to 200 km/h inclusive.
For wheel sets of TRS with a design speed over 200 km/h, the difference in dimensions C for one wheel set shall not exceed 1.0 mm.
Symmetry tolerance T of the distance between the inner ends of the tires (rims) of the wheels must be equal to the value of the tolerance field for the size A according to 4.3.5 when using the center of the axle as a base (see Figure 2, base K).
4.3.10 Wheel sets with a gear wheel (gear wheels) fixed on the axle (elongated hub of the wheel center) for locomotives with a design speed of over 100 to 120 km/h (up to 130 km/h for MVPS wheel sets) are subjected to a check for residual static imbalance. The value of the residual static unbalance of the wheelset should be no more than 25 kg·cm. It is allowed for wheel sets to provide the value of residual static unbalance during their formation, taking into account the requirements of 5.1.3.
It is allowed to replace the check for residual static unbalance of wheel sets with a check for residual dynamic unbalance. The value of the residual dynamic unbalance of the wheelset should be no more than 25 kg cm in the plane of each wheel of the wheelset.
4.3.11 For wheel pairs of locomotives with a design speed of over 100 to 120 km/h with a toothed wheel (gears) fixed on the axle (elongated hub of the wheel center) and with an axial bearing housing fixed with the possibility of its rotation relative to the axle, the value of the residual static imbalance must be ensured when forming the wheelset. Wheel center imbalances are located in the same plane on one side of the wheelset axle. The total value of the residual static imbalance of the wheel centers should not exceed 25 kg cm.
It is allowed to replace the check for residual static unbalance of wheel sets with a check for residual dynamic unbalance.
4.3.12 Wheel sets with a gear wheel fixed on the axle for locomotives with a design speed of over 120 km/h (over 130 km/h for MVPS wheel sets) are subjected to a residual dynamic unbalance check.
The value of the residual dynamic unbalance in the plane of each wheel of the wheelset for locomotives must not exceed, kg cm:
12.5 - at v
7.5 - at v
The value of the residual dynamic unbalance in the plane of each wheel for MVPS wheelsets should not exceed, kg cm:
25 - at v to over 130 to 160 km/h inclusive;
15 - at v to over 160 to 200 km/h inclusive.
For TRS wheelsets with a design speed over 200 km/h, the value of the residual dynamic imbalance in the plane of each wheel should not exceed 5.0 kg cm.
4.3.13 A wheel set of the TRS, on which the gear wheel is installed in a bearing support, enclosing the axle of the wheel set and fixed on the traction motor, and the transmission of torque to the wheel set is carried out by means of a hollow shaft or an axial gearbox, having the possibility of relative movement in the longitudinal and transverse directions relative to the axis of the wheelset, subjected to a test for residual dynamic imbalance when fixing the bearing support with the gear wheel in the middle position relative to the axis. The value of the residual dynamic unbalance - according to 4.3.12.
It is allowed to subject such a wheel pair to a test for residual static imbalance and provide the value of static imbalance separately for the constituent elements of the wheel pair (wheel centers of composite wheels, parts of the drive of the wheel pair connected to the wheel center located on the side opposite to the gear wheel) when it is formed taking into account requirements 5.1.3.
The total value of the residual static imbalance of the wheelset should not exceed, kg cm:
25 - at v to over 120 to 160 km/h inclusive;
15 - at v to over 160 to 200 km/h inclusive.
4.3.14 Paint and varnish coatings of wheel sets of locomotives and tenders - in accordance with GOST 31365, wheel sets of MVPS - in accordance with GOST 12549.
For wheel sets of TRS with a design speed of more than 200 km/h, the disk parts of the wheels and the open parts of the axle must be protected with an anti-corrosion coating.
4.3.15 The electrical resistance between the tires (rims) of wheelset wheels should be no more than 0.01 Ohm.
4.3.16 Use in wheelsets of a wheel center with a disk part, the deformation of the shape of which causes, during operation, an excess of tolerances for the distance between the inner ends of the wheel rims (size A, 4.3.5) due to heating of the elements of the wheelset during prolonged and / or intensive braking by brake pads on the tread surface of the tires, reduction of the thickness of the tires due to wear and repair turning of the tread surface of the tires is not allowed.
4.3.17 Permissible safety factor for axle and wheel fatigue resistance as part of a wheel pair for a specific TRS, taking into account the effect of technological and operational loads - in accordance with GOST 31373.
4.3.18 Probability (calculated) of failure-free operation of the axle and wheel as part of a wheel pair for a specific TRS, taking into account the effect of technological and operational loads - according to GOST 31373.
4.3.19 The endurance limit of the axle and wheel as part of a wheel pair for a specific TRS, taking into account the effect of technological and operational loads - according to GOST 31373.
4.3.20 Permissible safety factor for the static strength of the axle and wheels as part of a wheel pair, taking into account the effect of technological and operational loads - in accordance with GOST 31373.
4.4 Marking
Marking and branding of axles of MVPS wheelsets - in accordance with GOST 31334.
The marking of the axles of wheel pairs of locomotives after formation and branding after acceptance tests are applied on the right end of the axle according to Figure 7.
With a one-sided drive, the right end is considered the end of the axis from the side of the gear. With a double-sided drive or a symmetrical arrangement of the gear, marking and branding is performed on any end free for branding and marking. Such an end face with marking and branding is considered right.
When conformity is confirmed after certification, the wheelsets are marked with the sign of circulation on the market in the places where the hallmarks related to the repair of the wheelset are placed, as well as in the wheel set form. If the design features of the wheelset do not allow marking the mark of circulation on the market at the end of the axle, the mark of circulation on the market is put on another surface indicated in the technical documentation or only in the form.
Zone I(applied during the manufacture of the axis)
1
- conditional number or trademark of the manufacturer of the raw axle;
2
- month and year (last two digits) of the production of the rough axle;
3
- melt serial number and axis number; 4
- stamps of technical control of the manufacturer
and the representative of the acceptance, who checked the correctness of the transfer of the marking and accepted the finishing axis;
5
- conditional number or trademark of the manufacturer who processed the rough axis
Zone II(applied when forming a wheelset)
6
- designation of the wheel pair formation method [FT - thermal, F - press,
TK - combined with the thermal method of landing the wheel (wheel center) and the press method
landing of the gear wheel on the axle, TK - combined with the thermal method of landing the gear wheel
and the press method of landing the wheel (wheel center) on the axle]; 7
- conditional number or trademark
the enterprise that produced the formation of the wheelset; 8
- month and year of wheel formation
couples; 9
- stamps of technical control of the manufacturer and acceptance representative,
who accepted the wheelset; 10
- balancing mark
Note - If the ends of the axles are working elements of the design of the axlebox units, then the markings and stamps are knocked out on the cylindrical surface of the collars or other non-working surface indicated on the working drawing; the height of numbers and letters is from 6 to 10 mm.
Figure 7 - Marking and branding of wheelset axles
4.5 Requirements for accompanying documentation
A form is attached to each wheel pair. In the wheel pair form indicate:
Type (name);
Name and conditional number of the manufacturer;
date of manufacture;
Date and number of the acceptance certificate by the manufacturer;
Designation of the wheel pair drawing;
Data on the axle, solid wheels or wheel centers and tires (casting manufacturer, heat number);
Manufacturer and designation of the drawing of the axle, solid wheels or wheel centers and tires;
The initial dimensions of the main parts of the axle (diameters of journals for rolling and plain bearings, pre-hub and hub parts, diameter of the middle part of the axle), fitting diameters of wheel hubs or wheel centers, outer fitting diameters of wheel centers and inner diameters of tires, wheel diameters along the tread circle and thickness ridges, as well as the thickness of bandages.
The wheel pair form must contain pages for indicating the inspections and repairs carried out at the depot or at the repair plant (date, type of repair, mileage, actual dimensions).
The form for the gear wheel(s) must be attached to the form for the wheelset.
5 Formation of wheelset
5.1 General
5.1.1 The wheelset should be formed by thermal, pressing or combined methods.
5.1.2 With the combined method of forming a wheel pair, the wheels (wheel centers) and the hubs of the brake discs are mounted on the axle by the pressing method, and the gear wheel - by the thermal method. Other combinations of methods for forming the constituent elements of the wheelset are allowed.
5.1.3 When forming TRS wheelsets with a design speed of more than 100 km/h, the unbalanced masses of the wheel centers should be located in the same plane on one side of the axle.
5.1.4 The design of the wheelset must provide channels for supplying oil under pressure to the connection area of the wheel, gear wheel (gear wheel hub) and brake disc hub with the axle to disassemble the wheel pair (oil removal).
5.2 Thermal shaping method
5.2.1 Wheelsets are formed by the thermal method in accordance with the requirements of ND * approved in the prescribed manner.
GOST R 53191-2008.
5.2.2 Local heating of a solid wheel hub, gear wheel or wheel center assembly with a tire is not allowed.
From 0.85 10 -3 to 1.4 10 -3 diameters of mating parts for hubs of wheel centers and wheels;
From 0.5 · 10 -3 to 1.0 · 10 -3 diameter of mating parts for gear wheel hubs and brake discs.
5.2.4 The seating surface of the axle must be coated with an anti-corrosion coating.
It is recommended to use natural drying oil according to GOST 7931 or heat-treated vegetable oil (sunflower oil according to GOST 1129** or linseed oil according to GOST 5791) as an anti-corrosion coating for the seating surfaces of the axle. It is allowed to use other anti-corrosion coatings that have passed the tests for resistance to fretting corrosion of mating parts and do not reduce the fatigue strength of the axis.
** On the territory of the Russian Federation, GOST R 52465-2005 applies (hereinafter).
5.2.5 Before forming, the parts mounted on the axle, except for gears, are uniformly heated to a temperature of 240 °C to 260 °C and the heating diagram is recorded. Heating temperature of gear wheels made of alloyed steels - no more than 200 °C, gear wheels made of steel grade 55 (F) *** - no more than 260 °C. The heating temperature of gears containing non-metallic elastic elements should not exceed 170 °C.
*** On the territory of the Russian Federation, these requirements are established in GOST R 51220-98.
5.2.6 After completion of the formation by the thermal method and cooling of the assembled wheelset to a temperature not exceeding the ambient temperature by more than 10 °C, the strength of the connection of the elements of the wheelset for the TRS with a design speed of not more than 200 km/h must be checked for a shift of the control axial load:
(636 ± 20) kN [(65 ± 2) tf] - for every 100 mm of the diameter of the axle hub parts for the fit of running wheels or wheel centers for wheel pairs of locomotives;
(568 ± 20) kN [(58 ± 2) tf] - for every 100 mm of the diameter of the axle hub parts for the fit of running wheels or wheel centers for MVPS wheel pairs;
(432 ± 20) kN [(44 ± 2) tf] - for every 100 mm of the diameter of the axle hub parts for fitting a gear wheel or hub of a compound gear wheel (one or two) for wheel sets of locomotives with a nominal wheel diameter in the tread circle of at least 1200 mm;
(294 ± 20) kN [(30 ± 2) tf] - for every 100 mm of the diameter of the hub parts of the axle for fitting a gear wheel or hub of a compound gear wheel (one or two), a brake disc hub (one or two) for TPS wheelsets with a nominal diameter of the wheel in a circle of rolling up to 1200 mm;
(245 ± 20) kN [(25 ± 2) tf] - for every 100 mm of the diameter of the elongated hub of the wheel center for the fit of the gear wheel.
It is allowed to increase the set maximum value of the control axial load by 10%, taking into account the established interference.
It is allowed to check the fit of the gear wheel on the elongated hub of the wheel center with the control torque (9.8 ± 0.8) kN m [(1.0 ± 0.08) ton m] per square of every 100 mm of the diameter of the elongated hub of the wheel center. After landing the gear wheel on the elongated hub of the wheel center, a control mark is applied to the plane adjacent to the seating surface. The control mark is applied with a blunt tool in the form of a groove with a depth of not more than 0.5 mm and a length of not more than 10 mm.
For TRS wheel sets with a design speed over 200 km/h, the control axial load in kilonewtons should be taken in the range of 5.2 - 5.8 d (d- diameter of the axle hub part, mm) in accordance with the tightness established in the design documentation for a given connection (running wheel, wheel center, gear wheel, composite gear wheel hub, brake disc hub with axle).
Shift or rotation (displacement of control marks) in the connection is not allowed.
5.3 Press forming method
5.3.1 Parts mounted on the axle (wheels, wheel centers or wheel centers complete with tires, gear wheels, brake disc hubs) and the axle must have the same temperature before pressing. It is allowed to exceed the temperature of the wheel above the temperature of the axle by no more than 10 °C.
5.3.3 The seating surfaces of the axle and parts mounted on the axle must be covered with an even layer of natural drying oil in accordance with GOST 7931 or heat-treated vegetable (hemp in accordance with GOST 8989, linseed in accordance with GOST 5791 or sunflower in accordance with GOST 1129) oil. It is allowed to use other anti-corrosion coatings that have passed the tests for resistance to fretting corrosion of mating parts and do not reduce the fatigue strength of the axis.
5.3.4 Pressing the parts onto the axle and checking for shear by the control-axial load is carried out on a hydraulic press. The press must be equipped with a calibrated force control device and an automatic recording device that records on paper or electronic media a diagram of the pressing force of the wheel (wheel center), gear wheel, brake discs relative to the seat during the entire pressing operation.
The accuracy class of the recording device must be at least 1.5%, the error of the chart course should not exceed 2.5%, the thickness of the recording line should not exceed 0.6 mm, the width of the chart tape should be at least 100 mm, the recording scale along the length should be not less than 1:2, along the height of the diagram 1 mm must correspond to a force of not more than 24.5 kN (2.5 tf).
5.3.5 Pressing the wheels (wheel centers) onto the axle and pressing the gears onto the axle or wheel center (brake disks) for wheel sets of the TRS with a design speed of not more than 200 km/h is carried out with final pressing forces, which must correspond to those indicated in the table 1, when the speed of the hydraulic press plunger is not more than 3 mm/s.
Table 1 - Final pressing forces when forming a wheel pair by pressing
|
Wheel set detail |
Final pressing force for every 100 mm diameter of the seating surface, |
||
|
Composite wheel (solid wheel) |
wheel center |
||
|
locomotive axle |
|||
|
gear wheel brake disc |
|||
|
Brake disc hub |
|||
|
* When pressed onto an extended wheel center hub. ** In the numerator, the values are for wheelsets with wheel diameters up to 1200 mm, in the denominator - over 1200 mm. |
|||
5.3.6 Pressing wheels, brake discs and gear wheels onto the axle for wheel sets of the TRS with a design speed over 200 km/h is carried out on the diameter d in millimeters with final press-in forces in kilonewtons ranging from 3.9 to 5.8 d with mating length from 0.8 d up to 1.1 d.
5.3.7 A normal pressing indicator diagram should have the form of a smooth curve, slightly convex upwards, growing along the entire length from the beginning to the end of the pressing. A template - a diagram of the pressing of wheel sets is shown in Figure 8.
The following deviations from the normal shape of the pressing pattern are allowed.
1
- field of satisfactory pressing diagrams; 2
- maximum curve; 3
- minimum curve;
P- pressing force, kN; P max , P min - respectively, the maximum and minimum final forces
pressings in accordance with table 1; L- theoretical length of the chart, mm
Figure 8 - Template - pressing diagram
5.3.7.1 At the starting point of the diagram (the zone of transition of the conical part into the cylindrical part), an abrupt increase in force of no more than 49 kN (5 tf) with a subsequent horizontal section of not more than 5% of the theoretical length of the diagram L.
5.3.7.2 Presence of areas or depressions on the diagram at the location of recesses for oil channels on the hubs, the number of which must correspond to the number of recesses.
5.3.7.3 Concavity of a diagram with a continuous increase in force, provided that the entire curve, except for the lands and valleys specified in 5.3.7.2, is placed above the straight line connecting the beginning of the curve with a point indicating the minimum allowable force in this diagram P min for the given axis type.
5.3.7.4 Horizontal straight line on the diagram at the end of the press-in for a length not exceeding 15% of the theoretical length of the diagram L, or force drop no more than 5% of the pressing force P max on a length not exceeding 10% of the theoretical diagram length L.
5.3.7.5 Stepwise increase in force at the end of the diagram, if the design of the wheelset or the technology of formation provides for a fit to the stop in any element.
5.3.7.6 Force fluctuation at the end of the press-in with an amplitude of not more than 3% of the press-in force P max on a length not exceeding 15% of the theoretical diagram length L when pressing wheels with an extended hub.
5.3.7.7 Deviation from measurement accuracy up to 20 kN (2 tf) when determining the maximum maximum force from the diagram.
5.3.7.8 If the final pressing force of wheel pairs is up to 10% less or greater than the limit value of the range specified in Table 1 (without taking into account the permissible stepwise increase in force according to 5.3.7.5), the manufacturer, in the presence of the customer, must check the press fit by applying a test axial load three times in the opposite direction from the pressing force. To check the reduced final press-in force, the reference axial load must be equal to 1.2 times the actual press-in force. To check the increased final press-in force, the reference axial load must correspond to the maximum press-in force according to table 1.
5.3.7.9 The actual length of the pressing pattern shall be at least 85% of the theoretical length of the pattern L, mm, which is calculated by the formula
L = (L 1 + L 2) · i,
where L 1 - length of the contact area of the hub of the wheel center with the axle, mm;
L 2 - additional advancement of the hub (if provided for in the design documentation), mm;
i- the scale of the chart in length.
The actual length of the pressing pattern for the brake disc hub must be at least 105 i.
5.3.7.10 If an unsatisfactory diagram is obtained or the value of the final pressing force does not correspond to the value specified in Table 1, it is allowed to re-press (no more than two times) the wheel (wheel center) onto the axle without additional machining of the seating surfaces in the absence of burrs on the seating surfaces of the axle and wheel hub ( wheel center).
When re-pressing the wheel (wheel center) onto the axle, the value of the lower limit of the final force specified in Table 1 must be increased by 15%.
6 Acceptance rules
6.1 Wheel sets are subjected to control for compliance with the requirements of this standard during acceptance tests (PS), periodic (P), type (T) tests in accordance with GOST 15.309 and tests for confirmation of conformity (C).
The list of controlled parameters and test methods for the wheelset is given in Table 2.
table 2
|
Controlled parameter |
Clause of the standard containing the requirements that are checked during testing |
Test method * |
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|
acceptance |
periodical |
for confirmation of compliance |
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1 Dimensions, tolerances and shape |
4.2.1.2 - 4.2.1.4, 4.2.2.2, 4.2.2.4, 4.2.2.5, 4.2.2.9 - 4.2.2.11, 4.2.2.17 - 4.2.2.19, 4.2.3.2, 4.3.1 - 4.3.6, 4.3.8, 4.3.9 |
4.3.3 - 4.3.6, 4.3.9 |
7.1.2, 7.1.4 (PS, P, T), 7.1.5 |
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2 Appearance and condition (quality) of the surface, including the finish (roughness) |
4.2.1.1, 4.2.2.3, 4.2.2.8, 4.2.2.9, 4.2.3.1, 4.3.7, 4.3.8 |
7.1.1 (PS, S), 7.2 (P, S) |
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3 Mechanical properties and chemical composition |
7.1.15 (PS), 7.2 (P) |
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4 Roll hardening |
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5 Heating temperature of mating parts |
4.2.2.16, 4.2.2.17, 5.2.2, 5.2.5, 5.3.1 |
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6 The presence of defects in the metal: |
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Ultrasonic control |
4.2.1.5, 4.2.2.12, 4.2.2.13 |
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Magnetic control |
4.2.1.5, 4.2.2.13, 4.2.3.3, 4.2.11 |
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Acoustic control |
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7 Imbalance: |
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Static |
4.2.2.14, 4.3.10, 4.3.11, 4.3.13, 5.1.3 |
4.3.10, 4.3.11, 4.3.13 |
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Dynamic |
4.3.10, 4.3.12, 4.3.13 |
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8 Preload value of mating parts |
4.2.2.15, 5.2.3, 5.3.2 |
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9 Strength of connection of mating parts |
4.2.2.17, 5.2.6, 5.3.5 - 5.3.7 |
5.2.6, 5.3.4 - 5.3.6 |
7.1.10 (PS, S), 7.1.11 (PS), 7.2 (P, S) |
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5.3.7.1 - 5.3.7.9 |
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10 Profile parameters of the tire (rim) of the wheel in a circle of rolling |
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11 Electrical resistance |
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12 Wheel center shrinkage due to plastic deformation |
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13 Changing the distance (size BUT) from heating during braking and reducing the thickness of bandages during turning |
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14 Fatigue resistance factor of the axle and wheels as part of the wheelset |
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15 Static strength factor of the axle and wheels as part of a wheel pair |
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16 Endurance limit of the axle and wheel as part of the wheelset |
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17 Probability (calculated) of failure-free operation of an axle and a wheel as part of a wheelset |
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18 Marking |
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19 Color quality |
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* For parameters not marked by types of tests, tests are carried out for all types of tests. |
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6.2 Acceptance tests
6.2.1 Acceptance testing of parts of a wheel set and each wheel set as an assembly must be carried out prior to their painting with the presentation of certificates, other documents confirming the quality, charts for checking wheels for shear or pressing charts, as well as forms for wheelset and gears.
6.2.2 On the elements and the wheelset that have passed the acceptance tests, the manufacturer's acceptance stamps must be applied, and if they are also carried out by another control organization, its acceptance stamp.
6.2.3 In case of non-compliance with the requirements of this standard, the parts of the wheelset prepared for assembly and the wheelset must be rejected.
6.3 Periodic testing
6.3.1 Periodic tests should be carried out at least once a year in the scope of acceptance tests, and it is necessary to additionally control:
The quality of surface treatment - on two parts of each design;
The quality of rolling hardening - in accordance with GOST 31334;
The strength of the bandage connection with the wheel center is on two pairs of wheels from each standard size of the bandage.
6.3.2 In case of non-compliance with the requirements of this standard on at least one sample (part), the tests are repeated on twice the number of wheel sets. In case of unsatisfactory test results, the acceptance of wheel sets is stopped until the cause is eliminated.
6.4 Type tests
6.4.1 Type tests should be carried out:
When changing the design of the wheelset (by parameters 1 - 3, 5, 7 - 17 of Table 2);
When using materials with other mechanical properties, changing the technological process for manufacturing wheel pair parts and their blanks, or changing the manufacturer (by parameters 1 - 6, 8 - 10, 12, 14 - 17 of Table 2);
When changing the method of forming a wheelset (by parameters 1, 2, 4, 5, 8, 9, 12 of Table 2);
In case of changes in the braking system that affect the mechanical or thermal load on the wheel pair (wheel) (according to parameters 1 - 3, 5, 8, 9, 13 of Table 2);
With an increase in the axial load on the wheelset or design speed, a change in the loading pattern (according to parameters 1 - 5, 7 - 9, 13 - 17 of Table 2).
6.4.2 The conditions for carrying out type tests must correspond to the operating conditions of wheel sets in terms of the main parameters (static and dynamic loads from the wheel set on the rails, speed, traction and braking force).
6.5 Sampling rules for wheel sets
Tests to confirm the conformity of wheel sets are carried out on samples selected by random selection in accordance with GOST 18321, which have passed acceptance tests. The number of samples for testing to confirm the conformity of wheel sets is taken at least two.
7 Test methods
7.1 During acceptance tests, compliance with the requirements of this standard is determined by the following means and methods.
7.1.1 The appearance and quality of surface treatment must be checked by visual inspection using surface roughness samples in accordance with GOST 9378 or with a profilometer. The control of roughness parameters is carried out at three points equidistant from each other along the circumference.
7.1.2 Errors allowed when measuring linear dimensions - according to GOST 8.051.
When controlling dimensions over 500 mm, the maximum error of the particular measuring instrument used should not exceed 1/3 of the tolerance value established by this standard.
The radial and end runout is checked with a dial indicator and is determined as the arithmetic mean of the results of at least three measurements.
7.1.3 The value of the interference fit of the mating parts is determined before the formation of the wheel pair by measuring the fit diameters of their mating points with a micrometric caliper according to GOST 868 and a micrometric clamp according to GOST 11098 in three sections along the length of the fit and in two mutually perpendicular planes. The average value of the results from every six measurements should be taken as the value of the diameter of the measured place of mating of the parts.
It is allowed to use another measuring tool that provides the necessary measurement accuracy.
7.1.4 The correctness of the actual combinations of seating surface tapers should be checked by comparing the measurement results according to 7.1.3 according to the measurement values in two extreme sections along the seating surface fit length in two mutually perpendicular planes. For the value of the diameter in the extreme section of the landing, the average value of two measurements in each section should be taken.
7.1.5 The width of the compound wheel tire is measured in three sections along the circumference at a distance of at least 100 mm from the extreme numbers of the marking.
7.1.6 The profile of the tire (rim) of the wheel should be checked with an appropriate template with maximum deviations for its dimensions ± 0.1 mm. In the allowable gap between the template and the profile of the tire (rim) of the wheel, a probe with a thickness of more than 0.5 mm should not pass along the tread surface and the thickness of the ridge, 1 mm - along the height of the ridge, while the template must be pressed against the inner end of the tire (rim) of the wheel .
Magnetic control in accordance with GOST 21105 and acoustic control - in accordance with GOST 20415.
Note - When evaluating the results of ultrasonic testing, samples of the enterprise that identify the defect and have valid verification certificates are used.
7.1.8 Residual static or dynamic unbalance is checked on the wheelset or separately for the components when forming the wheelset in accordance with Appendix A.
7.1.9 The heating temperature of the parts of the wheelset before their landing should be controlled according to the heating diagram using instruments and devices that control the temperature rise, not allowing it to exceed its limit value. Measurement error - ±5 °C.
7.1.10 The strength of the connection of parts with the axis must be checked:
With the press fitting method - according to the shape of the pressing diagram and its correspondence to the final pressing forces in accordance with Table 1. To check the validity of the pressing diagrams, it is recommended to use an invoice template;
With the thermal method of landing - three times the application of a regulated control axial (shear) load to the joint, while loading diagrams are recorded.
The strength of the fit of the gear wheel on the elongated hub of the wheel center is checked by the control torque (for rotation) according to 5.2.6, while loading diagrams are recorded.
7.1.11 The tightness of the fit of the tire and compression of the tire ring on each wheel pair should be checked after the wheel has cooled down by tapping with a metal hammer (GOST 2310) on the tread surface and the tire ring at least at four equidistant points. Muffled sound is not allowed.
7.1.12 The electrical resistance should be checked on the wheelset installed on the supports of the device, which allows measuring the electrical resistance between the tires (rims) of the wheelset wheels according to ND * approved in the prescribed manner.
* On the territory of the Russian Federation, these requirements are established in GOST R 52920-2008.
7.1.13 Markings should be checked visual method. Wheels with illegible markings must be rejected.
7.1.14 Methods for quality control of painting wheel pairs of locomotives in accordance with GOST 31365, MVPS in accordance with GOST 12549.
7.1.15 The mechanical properties and chemical composition of the metal of wheel pair parts must be confirmed by documents on the quality of the enterprises producing blanks (forgings).
7.2 During periodic testing, compliance with the requirements of this standard is determined by the following means and methods:
The quality of surface treatment of parts before the formation of a wheelset - control of surface roughness parameters in accordance with GOST 2789;
The quality of hardening by rolling - cutting out longitudinal sections from the axes in the neck, sub-hub, middle part, and also selectively at the locations of the fillets according to RD ** approved in the prescribed manner;
** On the territory of the Russian Federation, these requirements are established in.
The strength of the bandage connection with the wheel center - by measuring the actual dimensions of the connection after removing the bandage, calculating the preload value and comparing it with the initial preload value;
The mechanical properties of the metal must be checked on cut samples - wheels according to GOST 10791, axles according to GOST 31334, wheel centers according to GOST 4491, tires according to GOST 398 or other approved ND.
7.3 For type tests, compliance with the requirements of this standard is determined by the following means and methods.
7.3.1 The decrease in the actual tightness (shrinkage) of the wheel center must be determined by measuring the diameters of the fitting surfaces of the mating parts in three planes at an angle of 120° along the entire circumference, before installation and after removing the bandage - according to 7.2, while the decrease in tightness should not exceed the specified in 4.2.2.15.
7.3.2 The change in the distance between the inner ends of the wheel rims due to heating during braking with the shoes on the wheel tread surface must be determined by the calculation method finite elements with idealization (breakdown) of the wheel by three-dimensional elements or an experimental method, by reproducing a long braking mode for 20 minutes at a brake pad pressure coefficient of up to 0.5 of the maximum at a speed of at least 40 km / h on long descents and stopping braking following lengthy.
7.3.3 The change in the distance between the inner ends of the wheel tires due to a decrease in the thickness of the tire (rim) due to wear and repair turning of the tread profile is determined by the finite element calculation method with the idealization (breakdown) of the wheel by volumetric elements or by the experimental method of layer-by-layer turning of the tread surface of the tire (rim) wheels from the maximum to the maximum thickness established in the rules for the technical operation of railways ***.
*** On the territory of the Russian Federation, these requirements are established in.
7.3.4 Determination of the value of the fatigue resistance factor of the axle and wheel as part of a wheel pair for a specific TRS, taking into account the effect of technological and operational loads - in accordance with GOST 31373.
7.3.5 Determination of the value of the endurance limit of the axle and wheel as part of a wheel pair for a specific TRS, taking into account the effect of technological and operational loads - in accordance with GOST 31373.
7.3.6 Determination of the value of the static strength factor of the axle and wheels and the probability (calculated) of the failure-free operation of the axle and wheels as part of a wheel pair, taking into account the effect of technological and operational loads - according to GOST 31373.
7.4 The test results are recorded in the test reports.
The test report must contain the following data:
date of testing;
Type of tests;
Wheel pair designation;
Measuring tool;
Test results.
7.5 The measuring instruments used must have type approval certificates and valid verification certificates.
The equipment used must be certified in accordance with the legislation on ensuring the uniformity of measurements.
8 Transport and storage
8.1 When loading wheelsets onto a railway platform or a car with wooden floors, they should be positioned symmetrically to the longitudinal axis of the platform (body), fixing the wheels with wooden wedges nailed to spacer boards attached to the floor of the vehicle. The wheelsets must be firmly attached to the floor with annealed wire 6 mm in diameter to prevent possible impacts of the wheelsets against each other. When transporting wheelsets on a railway platform or a car with metal floors, wheelsets should be installed on special supports, which are fixedly fixed on the vehicle.
8.2 During storage and transportation of the wheelset of the neck, the hub parts of the axles and the rims of the gear wheels must be coated with an anti-corrosion compound in accordance with protection groups 1 - 2, protection option VZ-1 in accordance with GOST 9.014.
Before transporting the wheelset, the necks of the axles and the teeth of the gears must be protected by tires - belts made of wooden planks strung on a wire or rope or nailed to a metal or keeper tape. Gear teeth should be wrapped with moisture-proof paper and protected from damage.
Metal tape, wire and nails should not touch the axle neck.
For long-term storage, it is allowed to additionally wrap the necks and gear wheels with burlap, glassine.
8.3 The axial bearings of the gearbox or traction motor must be covered with protective covers, and the bearings of the levers of the reactive moments of wheel pairs of diesel trains must be wrapped with burlap.
8.4 During transportation and storage it is not allowed:
Discard wheelsets and their elements;
Grab hooks and chains of lifting mechanisms of the neck and the tread parts of the axles of wheel pairs;
Store wheelsets on the ground without mounting on rails.
8.5 Each wheel pair must be affixed by the sender to a metal or wooden plate stamped or painted with the following data:
The name of the sender;
Destination,
Wheelset number.
In the case of delivery of a wheel pair with axle boxes, the bolt of fastening of the front cover of the right axle box must be attached metal plate with the wheel pair number stamped on it, if it is not stamped on the axle box body or front cover.
9 Manufacturer's warranties
9.1 The manufacturer guarantees that the wheel sets comply with the requirements of this standard, provided that the operating rules * and the requirements of section 8 are observed.
* On the territory of the Russian Federation, these requirements are established in.
9.2 Warranty period for the strength of the connection of parts (axle, wheel, wheel center, gear wheel) - 10 years.
Note - The warranty is terminated in case of re-formation of the wheelset.
9.3 Warranty periods operation of wheel pair parts:
Cast wheel centers - according to GOST 4491;
Other parts - according to specifications for a specific part.
Note - Warranty periods are calculated from the date of commissioning of the wheelset, indicating in the form the date of installation of the wheelset under the TRS.
10 Occupational safety requirements
10.1 When inspecting, surveying and forming wheelsets, labor safety requirements in accordance with GOST 12.3.002 must be met.
10.2 When carrying out work on the formation of wheelsets, measures should be taken to protect workers and the environment from the effects of hazardous and harmful production factors in accordance with GOST 12.0.003.
* On the territory of the Russian Federation, these requirements are established in the hygienic standards "Maximum Permissible Concentrations (MAC) harmful substances in the air of the working area" (GN 2.2.5.1313-03), approved by the Ministry of Health of the Russian Federation on April 27, 2003.
10.4 Work related to the production and testing of wheel sets must be carried out in rooms equipped with supply and exhaust ventilation in accordance with GOST 12.4.021.
10.5 Indicators of the microclimate of industrial premises must comply with the requirements of ND ** approved by the authorized national executive body.
10.6 The level of noise and vibration at workplaces should not exceed the standards established in the ND ** approved by the authorized national executive body.
** On the territory of the Russian Federation, these requirements are established in the “Hygienic Requirements for the Microclimate of Industrial Premises. Sanitary rules and norms” (SanPiN 2.2.4.548-96), approved by the State Committee for Sanitary and Epidemiological Supervision of Russia on 01.10.1996.
10.7 Illumination of industrial premises and workplaces must comply with the requirements of building codes and regulations.
10.8 Personnel involved in the production of wheelsets must be provided with personal protective equipment in accordance with GOST 12.4.011.
Annex A
(mandatory)
Checking residual static and dynamic imbalances
A.1 Checking the residual static unbalance
Residual static unbalance is checked on a wheelset installed with axlebox journals on the supports of a balancing stand. In the event of a spontaneous stop of a wheel pair swinging on the stand, the radius vector of the unbalance is directed downwards.
To determine the value of the residual static unbalance, pick up and attach to the top of one of the wheels at a radius r weight load m so that its imbalance is equal to the original imbalance.
mr = m 1 r 1 .
If the imbalances are equal, the wheel pair has a state of equilibrium on the horizontal supports of the stand in any of its positions when turning about the axis of rotation.
Residual static imbalance of wheelset D ost, kg cm, calculated by the formula
D ost = mr
and compared with the allowable values according to 4.3.10, 4.3.11, 4.3.13.
If the permissible value of the residual static imbalance is exceeded, the wheelsets are subjected to additional local turning, followed by a re-check.
m 1
- unbalanced mass of the wheelset; m- corrective mass;
r 1 , r- distance from the axis of rotation to the center of mass
Figure A.1 - Scheme of static balancing of the wheelset
A.2 Checking the residual dynamic unbalance
Dynamic unbalance is checked on a wheelset installed on a balancing stand. The stand must ensure the registration of an imbalance of at least 0.2 of the maximum value established by the requirements of this standard.
The values of the residual dynamic imbalance of the wheelset are determined by measuring the dynamic impact of the inertial forces of the rotating masses of the wheelset with the set speed and fixing their value and direction in the plane of the wheels. To do this, the stand is equipped with appropriate measuring sensors and recording equipment.
The obtained values of the residual dynamic unbalance of the wheelset are compared with the allowable values according to 4.3.12.
If the permissible value of the residual dynamic imbalance is exceeded, it is eliminated similarly to the static imbalance by local turning of the wheel, followed by re-checking.
Bibliography
|
TI 32 TsT-VNIIZhT-95 |
Technological instruction for hardening by rolling roller axles of wheel sets of locomotives and motor cars, approved by the Ministry of Railways of Russia on April 19, 1995. |
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|
Rules for the technical operation of the railways of the Russian Federation, approved by the Ministry of Transport of Russia on December 21, 2010, order No. 286 |
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|
Building codes and rules SNiP 23-05-95 |
Natural and artificial lighting, adopted by the Interstate Scientific and Technical Commission for Standardization and Technical Regulation in Construction as interstate building codes on April 20, 1995 |
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Introduction
The transport system of the country is an integral part of the industrial and social infrastructure of the state, ensuring its territorial integrity and national security. Railway transport in this system plays a key role in the socio-economic development of the Russian Federation, performing about 85% of the freight turnover and more than 37% of the passenger traffic of public transport. The growing demand for transport services requires major structural reforms, improvement of legal, economic and administrative mechanisms that regulate transport activity. Current state The transport system has the potential to support the development of the economy and the growth of the well-being of the Russian population in the future.
However, due to a number of serious problems associated with wear technical means and the level of accidents, the impact on environment and human health, there is a pushback of Russian carriers from a number of sectors international market transport services and a decrease in the quality of service for Russian enterprises and the population. To solve the above problems in ensuring the development of transport, improving the safety and efficiency of transport services, expanding transport services, priority measures have been outlined aimed at developing the transport complex.
First of all, creating effective system state management of transport, regulation and control of the transport services market, ensuring fair competition in the transport market and economic conditions for expanded reproduction in the transport complex. For this, it is necessary to form a unified legal framework for the activities of transport enterprises, taking into account international standards for the operation of transport. With the planned growth in traffic volumes, the problem of freight rolling stock is becoming a priority. AT last years the state of vehicles is approaching a critical level. Often the cars do not meet the needs of the clientele in terms of consumer qualities, carrying capacity, speed of delivery, labor intensity of loading and unloading operations.
Domestic car building plants are creating a new generation of freight cars, which are distinguished by increased reliability and efficiency. They have a reduced impact on the track, significantly reducing operating costs for routine maintenance and repairs. The designs and parameters of new cars provide for the expansion of specialization, the use of design solutions in bogies that ensure their normal operation without refurbishment from construction to the first overhaul and between overhauls. The new design of the bogies is made with a rigid frame and axle box suspension with an axial load of 245 kN (25 tf). Progressive design solutions are being introduced into the main elements of the body of the new generation of cars, ensuring the safety of the transported goods and the strength of its parts. The wheels are used with increased rim hardness, which ensures reduced wear of the ridges, and cassette-type axle boxes are introduced. Body structure elements are made of new anti-corrosion materials.
Mastering the production of passenger compartment cars of increased comfort is carried out using a new air conditioning system using an environmentally friendly refrigerant. New system heating of these wagons uses an ecological method of water regeneration. In the manufacture of the body, new fire-resistant materials, environmentally friendly toilets, new fire control and fire extinguishing systems, new service systems, etc. were used. Special compartments for the disabled are provided. New passenger cars are designed for a speed of 200-250 km/h, with centralized power supply, central diagnostics and remote control system.
The car park is one of the most important technical means. The quality of the transportation process, the timeliness of the delivery of passengers and goods, the productivity of transport and its economic indicators depend on the technical level of the rolling stock, its condition, number and composition, and the needs for transportation.
The most important characteristic of the wagon fleet is the percentage composition by types of wagons - the structure of the fleet, which depends on the composition of the transported goods or passenger requests. The criterion for the optimal structure of the wagon fleet is the full and high-quality development of a given volume of traffic at minimal cost. The structure of the wagon fleet is constantly changing depending on the supply of new wagons and the exclusion of old types of wagons, and consequently, the production base, organization and technology of the wagon economy are being improved.
The wagon economy ensures the operability of the wagon fleet, maintaining the wagons in good technical and commercial condition, as well as the safe and uninterrupted movement of trains, carrying out scheduled preventive repairs and Maintenance wagons. Carriage economy, in addition, provides passengers with comfortable travel conditions.
To fulfill the above tasks, the wagon economy has the necessary production base, including wagon depots, wagon wheel workshops, washing and steaming enterprises, passenger service offices, laundries, as well as wagon maintenance points, points for preparing wagons for transportation, repair and outfitting depots, control points for automatic brakes and other structures and devices that are part of the wagon depot or section, within the territorial boundaries of which they are located.
To ensure the safety of train traffic in the wagon industry, automated diagnostic systems are used, which can significantly reduce the impact of " human factor"when detecting defects in wagons and ensure monitoring of the technical condition of the rolling stock in accordance with the current regulatory and technological documents, which significantly increases the safety of train traffic. Modernization of the existing wagon fleet and replenishment with new generation wagons, as well as operation will allow you to set the length of the warranty sections up to 1600 km To this end, to ensure traffic safety on the extended warranty sections of the railway, it is planned to install these complexes with an average distance between them of 25 km. at the beginning and end of the warranty sections.
1) The main structural elements andtechnicaldata
assembly unit
Wheelsets perceive static and dynamic loads, provide direct contact between the car and the track and direct the rolling stock to rail track, through them the load from the car is transferred to the rails, and the wheel sets rigidly perceive all the shocks and shocks from the unevenness of the track. When the rolling stock moves along curved sections of the track, additional loads appear on the wheelsets from the impact of centrifugal forces, and during braking - from braking forces. There are also cases when the wheels slide along the rails without rotation (they skid). In addition, the wheelset axles passenger cars interact with drive elements of electric generators.
A change in the mode of train movement, the passage of cars along curved sections and turnouts cause a change in the direction of the forces acting on the wheel pair and the redistribution of loads on its elements. Therefore, in the manufacture and operation of wheel pairs, high requirements are imposed.
Types of wheelsets, their main dimensions and specifications for manufacturing determined state standards. A special instruction establishes the procedure and terms for the inspection, examination and repair of wheel sets, as well as the application of signs and stamps on them. The most important norms and requirements for ensuring traffic safety are set out in the Rules for the Technical Operation of Railways (PTE).
Fig.1. Pair of wheels
The type of wheelset is determined by the type of axle and the diameter of the wheels.
The wheels are mounted on the axle at equal distances from its middle so that the distance between their inner faces is within the established limits (see Table 1.1). The correct position of the wheels and their strong connection with the axle are important conditions for ensuring the safety of the movement of rolling stock along the rail track. Wheel pairs are constantly checked for compliance with these conditions during the operation of the wagons.
The inner edge of the wheel has a 28mm high ridge. Such a height is sufficient to prevent derailment of the rolling stock and, at the same time, excludes the possibility of damage to the parts of rail fasteners and turnouts. The thickness of the ridge, measured at a distance of 18 mm from the top, for new and turned wheels is 33 mm. Due to the friction of the flange against the rail head in operation, this value decreases, therefore, limiting wear rates are established.
Table 1.1 Types of wheelsets and their main dimensions.
|
Wheelset type |
Axis assignment |
Wheel diameter, mm |
Used for wagons |
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For shrink fit rollers with nut end fastening |
Freight and passenger |
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For Shrink Fit Rollers with Washer End Mount |
Freight |
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For roller spigot fit with nut end fastening |
Freight and passenger |
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Parameter |
Main dimensions, mm: |
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The distance between the inner edges of the wheels (L) for wheel sets of cars operated in trains with travel speeds: Up to 120 km/h Over 120 to 160 km/h |
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Wheel diameters (D) in terms of wheelset rolling: -all types |
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Difference of distances between the inner edges of the wheels in one wheel pair, not more than: |
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Difference of wheel diameters along the rolling circle in one wheel pair, not more than: |
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Distance from the end face of the axle neck / to the inner edge of the wheel set of the type: |
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The difference in distances from the ends of the axle journals to the inner edges of the wheel rims on one and the other side of the wheelset, not more than: |
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Deviation from the alignment of wheel rolling circles relative to the axis of the base surface, not more than: |
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|
Rim Width: |
2 ) Periodicity, terms of repair and maintenance
During operation, wheel sets are subjected to inspection under the car, ordinary and complete inspection, as well as inspection with axle pressing out. Wheel sets are inspected under the car for all types of maintenance and current repair without rolling out from under the car, acceptance and delivery, at turnover points, as well as after a crash, accident, collision or derailment.
During the inspection, they check for sliders, captivity, dents, shells, dents, undercuts and pointed rolls of the ridge. At least once a month in each depot, all wheel sets of the car fleet are measured with special templates for rolled products and flange thickness. Ordinary examination of wheel sets of cars is carried out at the current repair of TR-3 and before each wheel set is rolled under the car. At the same time, the state of the wheel centers is checked by external inspection, the presence of appropriate signs and brands on the ends of the axle, the rolled products, the thickness of the ridge, the neck of the axle are examined with a magnetic flaw detector using templates.
A complete inspection of the wheel sets of the car is carried out during overhauls, repairs with depressurization of elements, in case of ambiguity or absence of brands and signs of the last inspection, damage to the wheelsets after an accident or crash. During a full inspection, the wheelset is cleaned from dirt and paint to the metal, the axle hub parts are checked ultrasonic flaw detector, replace worn or defective elements. After examination, stamps and signs of a full examination are applied to the axle of the wheelset. The results of an ordinary and full examination are recorded in a special journal and a technical passport of the wheelset, which also contains all the data related to the manufacture and operation of the wheelset. The wheel set survey with axle pressing out is carried out in all cases of failure to sound the axle with an ultrasonic flaw detector during a full survey, when two wheel centers are pressed, in the absence or ambiguity of formation marks and if the wheel set has not passed this type of survey. At the same time, all the work provided for a complete survey is carried out, as well as the axle is pressed out, its hub parts are checked with a magnetic flaw detector to identify surface cracks, after which stamps and survey marks are applied to the axle with the axle pressed out.
The service life of wheel sets depends on a large number of factors: on operating conditions, on the design of wheel sets, steel quality and manufacturing technology.
The actual wheel life can be determined using the following formula:
where H n is the thickness of the rim of a new solid-rolled wheel, H n = 75 mm;
H to -- the thickness of the wheel rim, worn out of the limiting dimensions, mm;
n - the number of turnings for the entire period of the wheel's service life;
h -- the average thickness of the removed metal layer for one turning, mm;
A - useful work of the car during the year, days;
Lcp - car mileage per day, km;
g - the average wear of the tread surface for 1 km of run, mm.
It follows from the analysis of the formula that the service life of the wheels can be extended by reducing the number of turnings and the thickness of the metal layer removed at each turning. Therefore, it is necessary to strictly monitor that when processing wheels in a rolling circle, a minimum layer of metal is removed.
The number of regrindings can be reduced through organizational and technological measures to improve the strength and reliability of wheel sets, which can be implemented in the following areas: reduction of axle tension in operation, technological ways to improve reliability. Axle tension reduction in operation can be achieved by eliminating additional force factors that arise in operation due to the formation of the previously considered wear and damage to the wheel tread surfaces, overload and uneven load distribution inside the car, malfunctions of spring-spring suspension systems, malfunctions and track irregularities.
Untimely eliminated defects of the wheel tread surfaces occupy a leading place in terms of their harmful effect on the strength of the axle.
These defects cause overvoltage constantly of the same fibers. It has been established that a slider up to 2 mm deep gives the highest accelerations up to 60g. These accelerations cause a significant overload of the axle and, in particular, the design force on the journal is increased by a factor of 2.
To reduce the tension of the elements of wheel sets, such an event as wheel set balancing is required, which is mandatory for wheel sets of cars operated at speeds above 140 km/h. Balance violation for speeds from 140 to 160 km / h is allowed up to 6 N * m.
Technological ways to improve the reliability of wheel sets have several directions - these are the methods of knurling the axles along the entire length, annealing the wheels before turning, restoring the necks with metallization, restoring the thread by automatic surfacing.
Currently, all new axles are knurled during the manufacturing process, while old axles are knurled directly after turning.
The rolling operation can increase the fatigue strength of the axle, reduce roughness and increase the surface hardness. The scheme of knurling axles with rollers is shown in Fig. 1.1
Rice. 1.1 Scheme of knurling the axle with rollers
For the hub part of the axle, the force P lies in the range of 18...28 kN. The knurling roller deforms the surface and creates directly in the section (1) under the roller in the surface fibers stresses that significantly exceed the yield strength, which gradually decrease deep into the part. After passing through the roller (section 2), the deep fibers of the metal, which have received stresses and deformations of elastic compression, tend to return to their original position, but this is prevented by the outer fibers that have received residual deformations.
As a result, although the axis diameter is larger behind the roller than directly under the roller, the size is not completely restored and residual compressive stresses are formed in the surface fibers. These stresses, summing up with the working tensile stresses, reduce the total stress state in one group of fibers, which leads to an increase in their fatigue strength. Another group of metal fibers, which is under operating compression stresses, receives an additional load. However, this does not cause serious damage, since the allowable compressive stresses are much higher than the allowable tensile stresses.
The rolling operation leads to an increase in surface hardness by at least 22% and is approximately HB 219 ... 229. The depth of the work-hardened layer after rolling of the hub part of the axle should be within 3.6 ... .7.2 mm. Surface roughness R a -- 1.25 microns.
Universal screw-cutting lathes are used to process the hub parts of the axle, as well as specialized turning-rolling machines, for example, models KZh1843 KZTS, Poremba (Poland) models TOA-40Z: and TOA-40W.
steel by switching to smelting in electric furnaces, followed by evacuation and purging with inert gases (argon) in order to remove non-metallic inclusions.
3) Typical malfunctions and damages, their causes and
ways to eliminate
Wheelsets are one of the main elements of the running gear, the technical condition of which significantly affects the reliability of the car as a whole. When a wheel set moves along a rail track, a set of static and dynamic vertical and horizontal forces acts on it. In addition, the wheelset axle experiences additional compressive stresses in the areas where the wheel hubs are pressed onto the axle and a number of other operational factors. The combination of a complex of these factors contributes to the occurrence of a number of faults in the elements of wheel sets. Malfunctions of axles of wheelsets are subdivided into general view for wear, cracks, breaks.
In the middle part of the axle, under operating conditions, a number of faults are formed, the location of which is shown in Fig. 2.1.
Fig.2.1. Malfunctions of the middle part of the axle
The most dangerous defects are transverse cracks 1. The analysis of a large number of axles with breaks in the middle part showed that the vast majority of cracks are of a fatigue nature and are caused by repeated repetition of cyclic loads, enhanced by the additional effect of loading cars in excess of the established norms, uneven distribution of cargo over the body, metal fatigue, the presence of stress concentrators, as well as defects in the wheel rolling surfaces (slider, chipping, etc.), causing additional dynamic loads. If transverse cracks are found in the axle, regardless of other parameters, the wheel pair is subject to disbandment. wheeled railway wagon
Longitudinal cracks 2 are formed due to the presence in the surface layers of the metal of defects of technological origin in the form of non-metallic inclusions, sunsets, captivity, nicks. Axles of wheel pairs with a longitudinal crack longer than 25 mm are replaced by serviceable ones. Rejection inclined cracks 3 depends on the angle of inclination b to the generating axis. At an angle of inclination of 30° or less, the crack is classified as longitudinal, and at an angle of more than 30°, it is referred to as transverse.
Cracks can be detected using ultrasonic or magnetic flaw detection, or visually (under PHE conditions) by a number of external signs. It has been established by practice that the paint film in the area of the crack does not adhere tightly to the axis, and in some cases it swells up in the form of a bubble or peels off. Deeper cracks can be detected in summer by the accumulation of dust, and in winter by the presence of frost. This is explained by the fact that moisture is concentrated in the crack, to which dust adheres in summer, and in winter the moisture turns into frost.
Ring workings on the middle part of the axle 4 arise from the friction of the vertical levers and horizontal rods, incorrectly assembled or incorrectly adjusted leverage of the brake or their fall on the axle. Significant wear depth can lead to axle breakage, so wheelsets with axle wear more than 2.5 mm deep are rejected.
Nicks and dents 5- mechanical damage, which is characterized by the formation of a local depression resulting from plastic deformation from an impact with an object (most often in the process of loading or unloading wheelsets). Axles of wheel pairs are rejected for these defects if the diameter of the axle at its location is less than the permissible one.
Curvature of the wheelset axle- mechanical damage with the formation of a bending of the axis as a result of its deformation from impacts during accidents and crashes. Curvature is determined by measuring the distance between the inner edges of the wheels at four points along the circumference or as a runout when the axle rotates in the centers. Wheelsets with a bent axle are not allowed for operation.
Defects in the hub part of the axle are mainly associated with the additional influence of pressing the wheel hub onto the axle. The most dangerous defect is a crack - a violation of the continuity of the metal in the zone of contact between the axle and the hub at the end. Immediately from the surface, cracks propagate at an angle of 70 ... 75 0 (Fig. 2.2) inside the sub-hub part of the axis, and then at a depth of 2 ... 4 mm it changes its direction to perpendicular to the surface. The slope of the crack from the axle surface is related to the pressure exerted by the ends of the wheel hub, in the sections of which the pressure increases by 1.5...1.8 times the normal pressure of the wheel hub after landing on the axle.
Fig.2.2. The nature of the formation of a crack in the sub-hub part of the axle.
The reason for the sharp decrease in the endurance of the axle in this zone is also damage to the axle surface due to friction corrosion (fretting corrosion), which develops on the surfaces of mating parts during cyclic loading. In addition, during contact friction, the processes of microwear, chemical oxidation of the surface occur, and electroerosive phenomena develop due to the thermoelectric current that occurs during friction of two metals.
Defects in axle journals:
Cracks in axle journals are most often formed near fillets. The main reason for their formation in the journals of axles with roller bearings is the local stress concentration in the area of the end face of the inner ring, especially near the rear fillet. The nature of these cracks is similar to the nature of cracks in the hub part, i.e. is a consequence of stress concentration over the cross section of the end face of the roller bearing inner ring. In order to reduce the stress concentration in this zone, it is necessary to make relief grooves near the rear fillet with a depth of 0.04 mm.
Seizures and risks on the necks and pre-axle parts - circular uneven wear along the transverse profile. On the journals and pre-hub parts with rolling bearings, transverse seizures and risks are formed due to the rotation of the inner rings of the bearings and labyrinth rings when the axle boxes are heated or the rings are not tight enough during installation.
Malfunctions of solid-rolled wheels:
The technical condition of the rolling surface and the crest has a huge impact on the smoothness of the car and the interaction with the tracks, especially when passing turnouts. The following groups of faults are distinguished: natural wear, thermomechanical damage, metal discontinuity.
The group of natural wear and tear includes such wear as different kinds rolled wheel tread surfaces, flange wear, sliders and others.
Uniform circular wear - rolling wheel rolling surface h (Fig. 2.3, a) in the plane of the rolling circle comes from the interaction of the wheel with the rail and the brake shoe. The formation of rolled products from interaction with the rail occurs as a result of the simultaneous action of two processes: the crushing of metal fibers at the contact area of the wheel with the rail and the abrasion of the metal under the action of friction forces that arise during braking from slipping of the wheel along the rail and the pad along the rim. The increase in rolling is also associated with plastic deformation.
In the initial period of running-in, the process of rolling stock formation proceeds 3 times faster than after running-in. During the run-in period; In addition to intensive wear of microroughnesses of the tread surface, there is a compaction of the upper layers of the metal and the formation of work hardening. The hardness of the work-hardened layer can reach HB 470. At the second stage of rolled product formation, the metal from the wheel-rail contact zone flows towards the outer edge of the wheel with the formation of circular sagging.
Rice. 2.3. Types of wheel tread wear:
1 - worn wheel profile;
2 - profile of an unworn wheel.
According to VNIIZhT, the average annual rental of freight car wheels is 2.8 mm. However, this rolling formation rate differs significantly for wheels with different rim thicknesses. So, for a new wheel of a freight car, 1 mm of rolled metal is formed in 37 thousand kilometers, and with a rim with a thickness of 30 ... 32 mm - in 22 thousand kilometers. This is due to the uneven distribution of the metal hardness of the new wheel rim over the thickness. So, at the tread surface of a new wheel, the hardness is about HB 300, and at a depth of up to 60 mm, about HB 270.
The average rate of formation of rolling in passenger cars is approximately 1 mm per 25 thousand km of run.
Circular wear uneven on a profile - stepped rolling(Fig. 2.3, b), in which a pronounced step is formed on the tread surface, occurs when the contact zone of the wheel with the rail is shifted, mainly due to the asymmetrical fit of the wheels on the axle, the large difference in the diameters of the wheels on the same axle along the tread circle, improper installation wheelset in a bogie. Step rolling, as a rule, is observed at one wheel of a wheel pair, and on the other wheel there is either increased wear or a vertical undercut of the wheel flange. The greatest depth of stepped rolling is at a distance of 25 ... 30 mm from the rolling circle towards the chamfer. Wheel pairs with stepped rolling are excluded from operation according to the norms of limiting uniform rolling, but more often according to the undercutting of the ridge on the other wheel.
Comb wear solid-rolled wheels are formed due to the intensive interaction of the wheel flange with the rail head. This process is intensified by abnormal operation of the wheelset, caused by incorrect installation of the wheelset in the bogie, a significant difference in the diameters of the wheels of one wheelset, asymmetrical fit of the wheels on the axle, and also due to the narrowing of the rail track. In all cases, the wheelset warps in the rail track and the frequency of the ridge running up on the side face of the rail head increases.
There are three types of ridge wear: uniform wear, vertical undercut (Fig. 2.3, c) and pointed rolling (Fig. 2.4, a).
Fig.2.4. Pointed rolling of the ridge (a) and circular influx of metal on the chamfer (b) of the wheel
Vertical undercut comb-- this is the wear of the ridge, at which the angle of inclination of the profile of the side surface of the ridge approaches 90°. Vertical undercut in operation is not allowed more than 18 mm in height.
Pointed reel(see Fig. 2.4, a) is a mechanical damage in which a protrusion is formed along the circular perimeter of the ridge at the point of transition of its worn side surface to the top. This defect occurs as a result of plastic deformation of the surface layers of the flange metal towards its top due to high contact pressure and intense friction in the zone of interaction with the rail head. The operation of wheel sets with a pointed reel is prohibited, as it is possible for the wagons to derail when cutting the anti-wool arrow.
Circular influx on the chamfer of the wheel rim (Figure 2.4, b) - this is the damage that occurs in wheel sets with a rolled product of 5 mm or more, when a further increase in the rolled product occurs due to plastic deformation of the displacement of the metal from the tread surface towards the chamfer. The passage of wheel pairs with this defect through the hump retarders leads to the formation of another defect - spalling of the circular influx of the wheel.
Spall off circular The influx of the wheel rim (Fig. 2.5, 7) occurs in the form of a circular spall in separate areas, or along the entire circle of the rim.
In operation, there is also local destruction - spalling metal at the outer edge in the chamfer area, which, as a rule, has a significant depth and length along the tread surface. This destruction occurs as a result of fatigue processes under the action of normal and tangential forces through the development of cracks that form at a depth of 8 ... 10 mm in the presence of a local stress concentrator in the form of shells, non-metallic inclusions, etc.
In operation, any spalls with a depth of more than 10 mm are not allowed, or if the width of the remaining part of the wheel rim at the spall is less than 120 mm, or if at the fracture site, regardless of size, there is a crack that propagates deep into the metal.
saddle steel(Fig. 2.3, d) - circular wear, uneven along the transverse profile of the rim, in which a concave saddle is formed on the tread surface,
Ring workings(Fig. 2.3, e) are wears in which local annular recesses of various widths are formed on the rolling surfaces of the wheels. These phenomena are observed, as a rule, in wheelsets interacting with composite brake pads. Annular workings are formed along the edges of the contact zone of the tread surface with the brake pad, and this pattern of their appearance is explained by the unequal thermal conditions of the surface layers of the metal of the wheel and the composite pad along the width of the contact zone and the impact of abrasive dust particles on the friction surface along the edges of the pad.
Wheel pairs with annular grooves with a depth of more than 1 mm at the base of the ridge and more than 2 mm near the outer edge of the rim or a width of more than 15 mm are not allowed for operation.
crawler(Fig. 2.5, 1) - local wear of the wheel, which is characterized by the formation of a flat area on the tread surface. The slider occurs when the wheel moves along the rail skidding due to the action in the contact zone of a complex of phenomena: heating of the contact zone to high temperatures, contact setting of the metal and severe plastic deformation.
The main reasons for jamming of wheel sets with brake pads, leading to skidding of the wheels, are malfunctions of brake devices, incorrect adjustment of the leverage, improper control of the brakes, changes in the mutual ratio of the friction coefficient of the brake pad to the wheel and the adhesion of the wheel to the rail (moistening of surfaces, lubricant ingress, etc.). ).
The sliders during the movement of the car cause impacts that lead to accelerated destruction of parts of the rolling stock and the superstructure of the track. It has been established by research that when a wheelset moves skidding with a static axle load of even about 20 tons, the intensity of the formation of a slider is 1 mm per 1 km of track. Wheel pairs with a slider deeper than 1 mm are not allowed for operation.
Fig.2.5. Wheel and axle failures
The high temperature of the slide zone leads, when the brakes are released and the wheelset is turned, to a huge heat transfer from the heated surface, at low ambient temperatures and the formation of hardening structures of the metal in the slide zone, which causes an increase in the brittleness of the metal and in the future can cause chipping of the metal from the slide zone and the formation of dents.
Vyshcherbina(Fig. 2.5, 2) - local destruction of the wheel rim in the form of chipping of the metal of the tread surface. The reason for their formation is thermomechanical damage, metal fatigue phenomena and thermal cracks in the rim. Cracks in places of thermomechanical damage and thermal cracks are formed under the action of tangential and normal forces during braking. The formation of dents is facilitated by the martensitic structure of the upper layers of the wheel metal, which has high hardness and brittleness. Large residual stresses of the hardened upper layer of the wheel metal cause the formation of microcracks, which, gradually developing, are interconnected and, as a result, the metal is chipped. Cracks in places of thermomechanical damage and in places of thermal cracks are characterized by a small depth, not exceeding 2...3 mm, and they usually have a group arrangement. Cracks in the places of fatigue cracks are characterized by a depth of significant dimensions, reaching 10 mm, an uneven surface with a characteristic type of fatigue failure, covered with an oxide film.
In winter (December-March), dents are formed 2-3 times more often than in April-November, which is due to the instability of the friction coefficient due to weather conditions, and hence the difficulty in choosing the correct braking mode. This is also due to the increase in gaps in the joints of the rails, leading to additional shock effects during the passage of wheel sets.
Metal gain(Fig.2.5, 3) on the tread surface - thermomechanical damage, in which U-shaped metal shear areas are formed on the tread surface. This form of plastic deformation with a maximum shift in the center of the contact strip and a minimum one at the edges is explained by the elliptical distribution of pressures on the contact area. The greatest deformations occur in the center of the contact area, where the maximum pressure is created, which develops in the direction of sliding of the wheels.
The build-up is located on the tread surface in the form of one or more zones, it can be single-layer and multi-layer. The build-up is determined by the shear height of the metal, measured from the undamaged tread to the peaks of the shear. The main cause of this defect is a violation of the braking regimes, as a result of which the wheel slips along the rail by 20 ... 30 mm for very short periods of time. At the same time, in the contact zone of the wheel with the rail, severe plastic deformation occurs with elements of contact setting and significant heating of the metal, which, firstly, leads to deformations, and, secondly, to hardening of this zone into martensite, which has increased hardness. Thus, the alternation of weld shifts is explained by a small slippage of the wheel due to an abrupt change in the adhesion force of the wheel to the rail.
The frequency of this defect has been increasing in recent years. This is due, on the one hand, to an increase in the speed of trains, their mass, at which it is necessary to extinguish the growing kinetic energy of the train, and on the other hand, the introduction of non-metallic blocks that provide a high braking effect, but poorly remove heat from the rolling surface during the braking period. So, when braking with cast-iron pads, 70% of thermal energy goes into the wheel body, and with non-metallic pads, up to 95%.
The build-up on the rolling surfaces causes increased shock loads on the rolling stock and the superstructure of the track, and therefore build-up with a height of more than 0.5 mm for wheel sets of passenger cars and more than 1 mm for freight cars is not allowed.
A significant proportion of wheel defects are mechanical damage, which include loose fit of the wheel hub on the axle, shift of the wheel hub.
Loose hub seat wheels is possible in case of violation of the technology of formation of the wheelset, non-observance of the equality of the temperature of the axle and the wheel when measuring the diameters of the landing surfaces, as a result of which the landing interference is incorrectly determined. Signs of a weakened fit are a break in the paint along the entire perimeter near the end of the hub in the place of its mating with the axle and characteristic corrosion and oil from under the wheel hub on the inside. Wheel sets with signs of weakening of the hub are subject to disbandment.
Wheel hub shift is the displacement of the wheel hub along the axis. This defect is also a consequence of a violation of the wheel pair formation technology or impacts in case of accidents.
The shift of the wheel hub leads to a change in the distance between the inner edges of the wheel rims and poses a serious threat to traffic safety, and therefore the wheel sets are excluded from service.
Cracks in the wheel hub and disc(Fig. 2.5, 4) - are formed under the action of a complex of dynamic forces due to the presence of metallurgical metal defects in these areas, non-metallic inclusions and irregularities from rolling the wheel during manufacture. In addition, cracks in the wheel hub develop from tensile stresses after the wheel is seated on the axle and the presence of microcracks on the edges that form when the hole in the wheel hub is pierced.
Longitudinal crack in the wheel rim(Fig.2.5, 5) - this is a violation of the continuity of the metal in the form of single longitudinal or transverse cracks. Such cracks occur due to the presence of foci of non-metallic inclusions or local heterogeneity of the wheel rim metal. These faults are detected by external inspection. If the thickness of the rim allows, the defect can be eliminated by turning on a wheel lathe. If the rim thickness is insufficient, then the wheelset is excluded from service.
Thermal transverse cracks in the wheel rim are formed in the form of many thermal fatigue cracks on the tread surface in the slope zones 1:7, on the chamfer and in some cases passing to the outer edge of the rim. Thermal fatigue cracks occur as a result of alternating intense heating of the wheel tread during braking and subsequent cooling. When the train brakes sharply, the friction surface of the wheel, especially with composite pads, heats up to a temperature of 400 °C, and in some areas the temperature can reach 1000 °C. Repeated cycles of heating and cooling induce sequentially in the surface layer of the wheel rim compressive and tensile stresses, the value of which can exceed the yield strength of steel, and this leads to the development of plastic deformation and, as a result, to the formation of cracks.
Cracks on the neck and pre-hub part of the axle(Fig.2.5, 6) - this is a violation of the continuity of the metal, which are characterized by the location most often near the fillets, as stress concentrates. The main reason for the formation of cracks in the journals of axles with roller bearings on a sleeve fit is the local stress concentration in the contact zone of the thin end of the adapter sleeve or the end of the inner ring of the bearing on a shrink fit.
Common causes of transverse cracks in axles are:
The phenomenon of metal fatigue;
Overloads caused by the presence of sliders and dents;
Incorrect arrangement of cargo on the body of the wagon;
Cracks are detected by external inspection and flaw detection during the inspection and repair of wheel sets. Wheelsets with cracked axles are taken out of service.
4) assembly unit repair technologyitzy
For wheel sets, depending on the amount of work performed, two types of repairs are established - without a change and with a change of elements. When repairing without changing elements in a depot, work is carried out to eliminate wear of the axle journals - knurling and grinding of the journals and welding without pressing out the elements.
Repair with the change of elements provides for the replacement of axles, wheel centers, repressing of weakened wheel centers, inspection of wheel sets with axle pressing. This type of repair is allowed to be carried out in wheel shops of repair plants and specialized workshops. For repair, wheelsets are rolled out from under the car.
Rental of wheel pairs is eliminated by turning on special machines with and without rolling out from under the car. Wheel pairs on the current repair of TR-3 are turned on wheel-turning machines equipped with a hydrocopy device. As the turning progresses, the thickness of the bandage decreases and its smallest thickness when released from the current repair is allowed 43 mm and not less than 50 mm for cars operating at speeds over 120 km/h. The outer profile of the tire during turning is controlled by a template, and the distances between the inner edges of the tires are controlled by a caliper. The template is tightly pressed against the inner edge of the tire, while the gap along the tread surface is allowed up to 0.5 mm, and in height and thickness of the ridge - up to 1 mm. In the conditions of the depot, the rental of tires without rolling out the wheelsets is eliminated during the maintenance of TO-4 on special wheel-milling machines KZh-20M. The machine is placed in a special ditch with removable rail inserts. To process the tires, the diesel locomotive is installed on a ditch, the traction motor is lifted slightly up with a jack, and the rail inserts are set aside, and the wheel pair is suspended on motor-axial bearings. The wheel pair rotates from the traction motor, which is powered by a current of 220--380 V. Calipers with cutters are brought to the bandages and the bandage is turned to the required dimensions. The processing time of one wheel pair is 30--40 minutes.
The worn surface of the ridge is restored by electric surfacing with special two-arc A-482 submerged arc devices or manually with wheel sets rolled out from under the diesel locomotive with subsequent processing on the machine. It is also allowed to weld the flanges of wheel sets without rolling out the wheel sets from under the car with a two-arc R-643 apparatus, followed by processing on a machine. Surfacing of worn surfaces of wheel pairs makes it possible to reduce the removal of metal from the bandage by about one and a half times during its turning to obtain a normal profile and extend the service life of the gearbox.
After processing the welded ridge, the K.P. is carefully inspected and checked with a flaw detector. Potholes (sliders) on the tread surface of the bandage are eliminated by turning or electric surfacing with subsequent processing (surfacing is not allowed for passenger cars). After fitting into the groove of the bandage, which has cooled down to a temperature of at least 200 ° C, a reinforcing ring is inserted and the side of the bandage is pressed.
The seating surfaces of the rim and hub of the wheel center, when worn, are restored by surfacing, followed by turning to a size that provides the necessary tightness.
Transverse and longitudinal risks and scuffs, nicks and traces of corrosion on the axle journals, not exceeding the permissible values, are cleaned. After cleaning the transverse cracks and nicks, the axle neck is subjected to flaw detection. Clogged or developed center holes are restored by electric surfacing, followed by machining according to the drawing.
The presence of transverse cracks on the necks is not allowed. If a longitudinal crack or film more than 25 mm long is found on the middle part of the axle, as well as longitudinal cracks or films on other parts of the axle, then the wheel pair is sent to a repair point for a complete examination.
When releasing wagons from the current TR-3 and overhauls wheel pairs are selected from among repaired or new formations with a difference in diameters along the rolling circle: no more than 12 mm when releasing from the current repair TR-3 and not more than 9 mm when releasing from overhauls that meet the requirements of the rules of technical operation, with zero rolling.
Under the formation of a wheelset is understood the manufacture of a wheelset from new elements. Replacing individual parts of the wheelset (axles, centers, gears) with new or good ones, but used, refers to the repair of the wheelset with the change of elements. Wheel centers are pressed onto the axle on a special hydraulic press in a cold state. Before pressing, the axles and wheel centers are sized to provide the necessary tightness, the seating surfaces are cleaned, wiped and lubricated with natural drying oil. The force when pressing the center with a bandage per 100 mm of the diameter of the hub part is (45-4-65) 104N, and when pressing the center without a bandage - respectively (40 4-60) 104N. In the process of pressing, a special indicator records the pressing diagram. Formation of the wheelset is completed by a full survey, branding and filling in the technical passport of the wheelset.
5) Assembly and testing technology
The technological process of repair and formation of wheelsets contains a significant number of operations performed sequentially and in parallel at specialized workplaces using high-performance equipment.
The wheel pairs received at the mechanical section of the wheel shop are subjected to a preliminary inspection and washing, which is carried out in a specialized washing machine. Then the wheelset enters the inspection site, which is equipped with a stand that allows you to rotate the wheelset during inspection. Ultrasonic, magnetic flaw detection with a flaw detector is also carried out here. Necessary measurements are made and the scope of repair is determined.
In the mechanical section of the wheel shop, wheelsets are repaired with and without replacement of elements. Wheelsets that do not require element change and performance welding work are sent to wheel turning machines. After turning, they are fed to the delivery site, where they are secondarily subjected to flaw detection.
The distance between the inner faces of the wheels after repair without changing the elements is 1440±3mm. The difference in distances between the inner faces of the wheels at various points is allowed up to 2 mm. The minimum and maximum width of the solid-rolled wheel rim is 126mm and 130mm.
The shape of the wheel profile is checked by the maximum template. It is allowed to deviate the outlines of the wheel from the profile of the cutout of the template along the height of the ridge 1 mm, along the tread surface and the inner edge 0.5 mm. The turning of the wheels along the rolling circle is carried out on wheel-turning machines of the latest model of the Polish company Rafamet KKVs-125, 1T-CH-A. The processing of the necks is carried out on special neck-rolling machines. The necks and pre-wheel parts for roller bearings are cleaned with sandpaper. It is allowed to leave small transverse and longitudinal risks, small teases.
When repairing wheel pairs, electric welding is used. Here, threading on the axles takes place, and the developed center holes of the axles are welded. After the formation of wheel sets and after repair, and examination, marks and stamps are placed on the ends of the axle, which are applied within the control circle. After testing the wheels for shift, the letter “F” is placed next to the formation sign on the right end of the axle. The received wheel pair is painted with black oil paint or black varnish and sent to the roller compartment. If the wheelset is not rolled immediately under the car, then it is conserved, the axle necks are coated with grease or technical vaseline and covered with protective wooden shields. According to the technical instructions for the production of welding and surfacing, when repairing cars, it is allowed to restore worn-out flanges of solid-rolled wheels by mechanized submerged arc surfacing. Before surfacing, the wheelset is machined on a wheel lathe in order to remove surface defects, heated in a muffle furnace to a temperature of 250 0 C, then the wheelset is installed on a modernized neck-rolling machine, on which surfacing heads of the A-580 type with a VS-600 rectifier are installed, automatic arc surfacing is carried out under a layer of flux, then the wheelset is placed in a thermostat for cooling, turned along the rolling profile, and ultrasonic flaw detection is performed.
The main advantages of this repair method are the high quality of the deposited metal and productivity. However, this technology leads to a change in the structure of the wheel metal and its unevenness in the thickness of the rim, a change in mechanical properties, the appearance of additional internal stresses, and high labor intensity of the work performed. The hub part of the old axle is turned before pressing the wheel in order to remove corrosion products, cracks, scratches and other defects, followed by hardening knurling with rollers.
The wheel pairs are pressed out, as a rule, on a press specially dedicated for this purpose. In cases where pressing out is performed on the same press as pressing in, the self-recording pressure gauge (indicator) and the working pressure gauge designed to control pressing forces must be turned off to avoid damage. The control over the shear forces in this case is carried out according to the second working pressure gauge.
When installing a wheel set on a press, it is necessary to ensure that its geometric axis of the wheel set and the press plunger coincide. After that, the press is turned on and the wheel is removed from the axle. The second wheel is removed in the same way.
For wheelsets with axles for roller bearings, a special cup is used to prevent thread deformation, damage to the ends, and flaring of the cylindrical part of the neck during disengagement.
If the wheel pair cannot be disbanded by the maximum force of the press, it is allowed to heat the wheel hub with a gas burner. But if, even after heating, the wheels cannot be removed from the axle, then if the axle malfunctions, the wheel hub is cut, and if the axle malfunctions, the wheelset is scrapped.
After wheel pairs are pressed out, previously rejected and marked elements (wheels, axles) are transported to platforms and racks for defective elements. Elements previously recognized as fit for further use are carefully inspected and measured. Based on the results of the inspection and measurement, the issue of further use of the wheel pair elements is decided. On the rejected elements with light paint, the sign “B” (marriage) and the conditional number assigned to the master are put.
Items suitable for further use are transported to the appropriate racks.
Processing of new and old-year axles is carried out on wire lathes.
The roughness of the machined surface and dimensions must comply with the drawings and technical requirements. The surface roughness of the axes is checked by standard standards.
6) Fundsmechanizationandautomation
Roll-out of wheelset:
The wagon bogie rolled out from under the depot repair car is transferred to the path of the wheel-turning department, the pin nuts are loosened
The trolley is moved by an overhead crane to the wheel pair assembly stand
Spinner nuts loosened
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The wheelset refers to rail transport and can be used in the running gear of railway rolling stock. The invention solves the problems of increasing the resource of the wheelset, improving maintainability, reducing maintenance and repair costs, improving driving performance, improving traffic safety and environmental safety in conditions of increasing speed, train weight and axle loads of the wheelset. The wheel pair includes two wheels with internal flanges on one solid hollow axle with a ratio of diameters ranging from 0.4 to 0.8, a conical interface, an average wheel tread line T with a tread circle diameter L, two outer and inner axle boxes, radial channels in the axle connecting the internal cavities of the axle and the cavities of the axle boxes, which are filled with liquid lubricant, sealing devices that prevent leakage of liquid lubricant from the axle boxes, a hydraulic pump placed on the axle is designed to circulate the coolant in the cavities of the bearing axle boxes. 1 ill.
The invention relates to rail transport, in particular to the running gear of railway rolling stock. A wheel pair is known, selected as an analogue, containing two wheels with internal flanges on one solid solid or hollow axle with two outer axle boxes that transfer the axle load with the help of bearings (Cars. Edited by L.A. Shadur. M .: Transport, 1980, p. 94, figure V.3). Known wheelset, selected for the prototype, containing two wheels with internal flanges on one solid axle with two internal or external axle boxes, transmitting the axle load by means of thrust bearings ( international standard ISO 1005/7. Rolling stock of railways, part 7. Wheel sets for rolling stock. quality requirements; Crap. 2, p. 17). However, the above known wheel sets (analogue, prototype) are made according to the traditional scheme, providing on one solid axle either only two external axle boxes, or two only internal ones, and have the following disadvantages, which reduce the resource, maintainability, increase the cost of maintenance and repair , reduce driving performance, traffic safety and environmental safety in the conditions of increasing speed, train weight and axle loads of the wheelset:
Increased stresses from bending in dangerous sections of the axle due to its asymmetric loading relative to the center line of the wheel, which, under conditions of cyclic bending deformations during movement, is the cause of the observed fatigue failures (statistics of wagon cuts show that due to the appearance of transverse at least 40% of the axles are rejected in parts of the axle, see Serensen SV, Shneiderovich OM, Groman MB Shafts and axles, Moscow, Gosmashtekhizdat, 1959);
Increased vertical asymmetric load on the axlebox assembly, thrust bearings, which leads with grease lubrication to conditions of semi-dry friction, heating of the axlebox assembly, intense wear, fatigue failure of cages, rings and rollers in rolling bearings, antifriction layer in plain bearings (statistics show that the proportion wagon cuts due to axle box heating due to bearing failures is up to 70%: see Proceedings of VNIIZhT, 1982, issue 654);
The impossibility of maintaining the wheel rolling circle in the vertical plane, which reduces driving performance, causes additional lateral impact of the wheel flange on the rail head and leads to the action of dynamic transverse forces on the axle bearing by means of a reflected shock wave, to the disorder of the rail-sleeper lattice, the transverse friction of the wheel on the rail, causing , as is known, the greatest wear on the contact surfaces;
The absence and impossibility of implementing, with the existing design of the wheelset (prototype), a closed system of forced lubrication with cooling of the axle bearings, which does not require the addition of lubrication for a long time of operation, and a reliable sealing system - due to watering of the lubricant, its dilution, ejection through the labyrinth seal and, for this reason, excessive wear of the centering surfaces and webs of the rolling bearing cage, depending on the class of cars, from 35 to 65%; see Tr VNIIZhT, 1978, issue 583). The objective of the invention is to increase the resource of the wheelset, improve maintainability, reduce maintenance and repair costs, improve driving performance, improve traffic safety and environmental safety in the face of increasing speed, train weight and axle loads of the wheelset. To solve this problem, a wheel pair containing two wheels with internal flanges on one solid hollow axle with two outer axle boxes is simultaneously equipped with two inner axle boxes, each of which with a corresponding outer axle box is placed on the axle symmetrically with respect to the centerline of the wheel tread, the ratio of the diameter of the hole of the hollow axle to its outer diameter in the range from 0.4 to 0.8, the interface of the wheel with the axle has a conical shape, while the small diameters of the cone are facing the ends of the axle, the internal cavities of the axle and the axle box are filled with an environmentally friendly lubricating-cooling fluid and are connected by radial channels made in the axle , a hydraulic pump is placed on the axis, the axle boxes are equipped with sealing devices in relation to liquid lubrication. The presence of new elements and connections makes it possible, while maintaining both the existing loads on the axle of the wheelset and the tendency to increase them, to increase the resource, maintainability, reduce maintenance and repair costs, improve driving performance, improve traffic safety and economic security due to the symmetrical relative wheel centerline of the load distribution on the axle and bearings, maintaining the wheel rolling circle in the vertical plane and at the same time halving: a) vertical equivalent loads on the support bearings, b) bending moment in the near-hub sections of the axle from vertical static load, complete unloading of the middle part axles from bending with an increase in fatigue strength and durability of axlebox units by more than two times, bending deformations of the axle by more than three times, providing a closed lubrication system for bearings. The specified new set of essential features is necessary and sufficient to solve the specified problem, which proves compliance with the criterion of eligibility for "novelty". Comparison of the proposed invention not only with the prototype, but also with other technical solutions in this field of technology did not reveal in them the features that distinguish the proposed invention from the prototype, which allows us to conclude that the criterion "inventive step" is met. The drawing shows a symmetrical part of the proposed wheelset. The wheel pair includes two wheels with internal flanges 1 on one solid hollow axle 2 with a ratio of inner and outer diameters d1/d2 ranging from 0.4 to 0.8, a conical shape of interface 3 of axle 2 and wheels 1, the middle line of rolling of the wheel T with a diameter rolling circle L, two outer 4 and two inner 5 axleboxes, radial channels 6 in the axle connecting the inner cavity 7 of the axle 2 and the cavity 8 of the axleboxes 4, 5, which are filled with a liquid lubricant such as, for example, "Tormob" fluid of the Canadian company "Thordon" , end-type sealing devices 9 are similar to the Sederval and Sons seal, Sweden (see "Shipbuilding Technology", 1991, No. 7), hydraulic pump 10, placed, for example, inside the axle cavity. The wheel pair works as follows. With a symmetrical arrangement of the inner and outer bearing boxes 4.5 relative to the center line T of the wheel 1, only the near-hub sections of the Z axis are subjected to bending, while the middle part of the axis of length A is completely unloaded from static bending. At the same time, the deflections and angles of rotation of the axle sections are reduced by more than three times, the difference between the angular displacements of the characteristic near-hub sections of the axle is significantly reduced: sections coinciding with the planes of adjacent rolling bearings axle boxes 4.5, with outer and inner planes of sealing devices 9 axle boxes 4.5; as a result, this reduces the effect of axial amplitude forces dangerous for bearings and sealing devices, caused by constraint of bending deformations, which, under conditions of rotation of a curved axis, leads to shock, friction and wear of the contacting parts. Further, if the stress in the calculated sections of the axis from the vertical static force acting on one bearing is halved, then the fatigue strength in accordance with the known experimental data and with the formulas of the probabilistic method for assessing the strength of the axis (see "Norms for the calculation and design of new and modernized of 1520 mm gauge MRS railway carriages (non-self-propelled)") more than doubled. Such a significant increase in the fatigue strength of axle 2 in dangerous sections and the unloading of its middle part due to redistribution of the load justifies the possibility of safely weakening the axle cross section by introducing an internal symmetrical capacitance in the axle without increasing the standard outer diameter by replacing the solid section with an annular one. This reduces the mass of the axle (on average by 100 kg) with all the known beneficial consequences, and the internal cavity 7 allocated due to the appeared reserve of axle strength is involved in the proposed closed lubrication system of the axleboxes 4.5 as a reservoir that simultaneously performs the functions of storing and cooling the lubricant washing axle bearings during movement. The range of 0.4 - 0.8 of the ratio of the diameters of the hollow axis d1 / d2 was chosen: a) the optimality conditions between the requirement to ensure strength, on the one hand, and an increase in the volume of the internal cavity used for the lubrication system (with a simultaneous decrease in the mass of the axis) - on the other; b) technology for manufacturing axles with a variable ratio d1/d2 along the length of the axle; c) the experience of using hollow axles, described, for example, in the book "Cars", ed. L.A. Shadur, M. : "Transport", 1980, pp. 94, 95, d) the behavior of the functions f=1-(d1/d2) 2 , w= 1-(d1/d2) 4 , respectively characterizing the cross-sectional area of the tubular axis and moment of resistance. Halving the equivalent radial forces acting on one bearing causes a significant increase in bearing life in millions of kilometers in accordance with the formula for evaluating the life of journal bearings (see "Calculation standards ..." mentioned above). Thus, the axle boxes turn out to be low-maintenance and with an increased resource, which leads to a decrease operating costs. With a symmetrical distribution of the load on the axlebox units 4.5, the plane of the rolling circle of diameter L of the wheel 1 is automatically set to a vertical position, which improves the driving performance of the vehicle and eliminates additional lateral forces on the rail and sleeper grid, reduces the effect of lateral friction of the wheel on the rail, wear of their surfaces. Environmental safety is also ensured in the event of an emergency (explosion, destruction of the box body, etc.), because the leaking lubricant does not pollute the environment, as it is environmentally friendly, soluble in water. The maintainability of the wheelset increases, and the repair costs are reduced due to the conical shape of the landing surface of the wheel 1 and axle 2, because injection of liquid onto such a mating surface provides convenient disassembly of the wheels. The hydraulic pump 10, located on the axle asymmetrically with respect to the wheels 1, causes the circulation of liquid lubricant in the cavity 7 of the axle 2 during movement, providing a closed lubrication system for axleboxes 4.5. An invention including such systemic related factors, as a conical connection of both wheels with the axle, allowing for a symmetrical distribution of the vertical load on the axle and bearings relative to the center line of the wheel, maintaining the wheel rolling circle in the vertical plane, significant unloading of the axle from bending, and bearings from radial forces and axial forces arising from - due to the constraint of bending deformations, as well as the creation of a closed system of environmentally friendly lubrication of bearings and a low-maintenance axle box, leads to such systemically related consequences as an increase in service life, an increase in maintainability, a reduction in maintenance and repair costs, an improvement in driving performance, an increase in traffic safety, which together create a super-effect under conditions of an increase in the speed of movement, the weight of trains and the loads on the axle of the wheelset.
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