Production and technological processes

The production process is a set of all actions, people and tools necessary for a given enterprise for the manufacture and repair of products.

The technological process is part production process, containing purposeful actions to change and / or determine the state of the object of labor.

There are the following technological processes:

production of blanks;

heat treatment;

mechanical and other processing of parts;

1. tests.

The structure of the technological process. Concepts; operation, setting, position, transition,workflow, acceptance. Technological and auxiliary operation, technological and auxiliary transition.

The workplace is a section of the production area, equipped in accordance with the work performed on it.

The technological process consists of technical and auxiliary operations.

A technological operation is a complete part of a technological process performed at one workplace.

A technological operation is a part of a technological process that is performed continuously at one workplace, on one or more simultaneously processed products, one or more workers with unchanged means of production.

During technological operation necessarily changes - the shape, size, properties of the object of labor.

During the auxiliary operation, the shape, dimensions and properties do not change (transportation).

All operations are performed in a certain sequence. The content, composition and sequence of operations is determined by the structure of the technological process.

Structure of technological operations

Operation  Set  Position  Transition  Move  Receive

Installation - part of the technical operation, performed with the constant fixing of the manufactured object of labor.

Position - any fixed position, invariably fixed workpiece, together with the device relative to the tool or fixed parts of the equipment to perform a certain part of the operation.

Transition is a completed part of a technical operation, performed by the same service station tools, with unchanged technical conditions. Technical transition is always associated with a change in the shape and size of the product.

Auxiliary transition - a completed part of the technical operation, consisting of human and equipment actions that do not change the properties, dimensions of the object of labor, but are necessary to complete the technical transition.

A move is a completed part of a technical transition, consisting of a single moving tool relative to the workpiece, accompanied by a change in the size of the shapes and properties of the workpiece.

Auxiliary move - part of the technical transition, consisting of a single movement of the tool, not accompanied by a change in the shape and size of the workpieces, but necessary to prepare the working move.

Reception - a complete set of human actions, when performing a transition, or part of it, accompanied by a single designated purpose.

The concept of technological support means,

To perform any technological process, a set of production tools is required, called technical equipment (STO). Service stations are subdivided into technological equipment and technological equipment.

Technological equipment serves to place material and workpieces in it and means of influencing them.

Technological equipment - additional technological equipment:

fixtures for fixing material and workpieces;

shaping tool - cutting tool;

measuring;

auxiliary tool - fixing the shaping tool

3.2 Technology transition

Technological transition is called the completed part of the technological operation, performed by the same means of technological equipment with constant technological modes and installation. If the tool was changed during the turning of the roller, then the processing of the same surface of the workpiece with this tool will be a new technological transition (Figure 3.3). But the tool change itself is an auxiliary transition.

Figure 3.3 - Scheme of technological transition

An auxiliary transition is a completed part of a technological operation, consisting of human and (or) equipment actions that are not accompanied by a change in the properties of the object of labor, but are necessary to complete the technological transition. Transitions can be combined in time due to the simultaneous processing of several surfaces, i.e. they can be carried out sequentially (roughing, semi-finishing, finishing turning of a stepped shaft or drilling four holes with one drill), parallel (turning a stepped shaft with several cutters or drilling four holes at once four drills) or parallel-sequential (after turning the stepped shaft simultaneously with several cutters, simultaneous chamfering with several chamfering cutters or drilling four holes in series with two drills).

Installation - a part of the technological operation, performed with the unchanged fixing of the workpieces being processed or the assembled assembly unit. Turning parts to any angle is a new setting. If the roller is first turned in a three-jaw chuck with one setting, and then it is turned over and turned, then this will require two settings in one operation (figure 3.4).

Figure 3.4 - Scheme of the first (a) and second (b) installation

3.3 Position

The workpiece installed and fixed on the rotary table, subjected to drilling, reaming and countersinking, has one setup, but with the rotation of the table it will take a new position.

A position is a fixed position occupied by a rigidly fixed workpiece or an assembled workpiece. assembly unit together with a device relative to a tool or a fixed part of the equipment when performing a certain part of the operation. On multi-spindle machines and semi-automatic machines, the workpiece, with one fixing it, occupies different positions relative to the machine. The workpiece is moved to a new position along with the clamping device (figure 3.5).

When developing a technological process for processing workpieces, it is preferable to replace setups with positions, since each additional setup introduces its own processing errors.

Figure 3.5 - Scheme of changing workpiece positions on a multi-spindle machine

3.4 Working and auxiliary stroke

The working stroke is the completed part of the technological transition, consisting of a single movement of the tool relative to the workpiece, accompanied by a change in the shape, dimensions, surface quality and properties of the workpiece. The working stroke usually accompanies the continuous processing of one layer of the workpiece, for example, on a lathe - processing the shaft per pass, on a planer - one movement of the cutter during cutting.

Auxiliary stroke is the completed part of the technological transition, consisting of a single movement of the tool relative to the workpiece, necessary to prepare the working stroke. For example, when rough turning a shaft, the cutter returns to its original position, making an auxiliary stroke.

3.5 Reception

A technique is a complete set of human actions used in the performance of a technological transition or part of it and united by one purpose. Usually, the reception is an auxiliary action of the operator when controlling the machine (manually), measuring the workpiece. Receive element - pressing a button, moving a handle, etc.

Important characteristics of the technological process and operation are the cycle, technological operation, tact and rhythm of release.

3.6 Cycle, beat and rhythm release

The cycle of a technological operation is a calendar time interval from the beginning to the end of a periodically repeating technological operation, regardless of the number of simultaneously manufactured products.

Tact is the time interval through which the release of products or blanks of certain names, sizes and designs is periodically performed.

The release rhythm is the number of products or blanks of certain names, sizes and designs produced per unit of time.

It is desirable that the time spent on the execution of one operation be equal to the release cycle time or a multiple of it. Such a correction of the time spent on the operation is achieved by varying degrees of concentration of operations, the use of optimal processing modes, the reduction of auxiliary time due to multiple devices, automation of loading, transportation, the use of more high-performance equipment, parallel operation on the same type of backup machines, etc.

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§ 22. STRUCTURE OF THE TECHNOLOGICAL PROCESS.

Operations, setups, positions, transitions, working and auxiliary moves and auxiliary transitions.

The technological process is divided into operations, installations, positions, transitions, working and auxiliary moves and auxiliary transitions.

A technological operation is a complete part of the technological process, performed at one workplace and covering all the actions of the worker and equipment performed with one or more simultaneously processed parts. Machining a different part or surface in a batch of identical parts is considered a new operation. For example, grinding one plate on one surface grinder on both sides is performed in one operation. If, on the other hand, a batch of plates is ground on one plate, first on one side and then on the other, then two operations are performed.

The installation is called a part of the technological operation performed with the unchanged fixing of the workpiece being processed or a group of simultaneously processed workpieces. Removal of the part from the machine with subsequent fixing is considered a new setup.

A position is a fixed position occupied by an invariably fixed workpiece, together with a fixture relative to a tool or a fixed piece of equipment, to perform a certain part of an operation.

Technological transition is called the completed part of the technological operation, characterized by the constancy of the tool used and the surfaces formed by the processing. Therefore, the transition from machining one surface of the workpiece to another surface is the next transition.

The working stroke is the completed part of the technological transition, consisting of a single movement of the tool relative to the workpiece, accompanied by a change in the shape, size, roughness or properties of the workpiece.

Auxiliary transition - a completed part of a technological operation, consisting of actions of a person and equipment or one equipment, which are not accompanied by a change in the shape, size and surface roughness, but are necessary to perform a technological transition (starting the machine, stopping the machine, turning on the feed, etc.) .

Auxiliary stroke is the completed part of the technological transition, consisting of a single movement of the tool relative to the workpiece, not accompanied by a change in the shape, dimensions, surface roughness or properties of the workpiece, but necessary to complete the work stroke.

working stroke called the completed part of the technological transition, consisting of a single movement of the tool relative to the workpiece, accompanied by a change in the shape, dimensions, surface quality and properties of the workpiece. The working stroke usually accompanies the continuous processing of one layer of the workpiece, for example, on a lathe - processing the shaft per pass, on a planer - one movement of the cutter during cutting.

Rice. 3. Workpiece processing in three working steps

Auxiliary move called the completed part of the technological transition, consisting of a single movement of the tool relative to the workpiece, necessary for the preparation of the working stroke. For example, when rough turning a shaft, the cutter returns to its original position, making an auxiliary stroke.

2.2.6. Reception. Reception call a complete set of human actions used in the performance of a technological transition or part of it and united by one purpose. Usually, the reception is an auxiliary action of the operator when controlling the machine (manually), measuring the workpiece. Receive element- pressing a button, moving a handle, etc.

2.3. Workplace. The workplace is called the elementary unit of the structure of the enterprise, where the performers of the work are located, serviced technological equipment, part of the conveyor, and for a limited time - equipment and objects of labor. Workplace - a section of the production area, equipped in accordance with the work performed on it (Fig. 1.9)

Rice. 1.9. Schemes of jobs for a machine operator (a) and an assembler (b):

The main elements of equipping the workplace :

Type of equipment Equipment elements

Main technological

equipment: machine tools, machines, units, automatic lines, etc.

Auxiliary equipment : assembly, test benches, conveyors and other means of transporting products, etc.

Technological equipment: fixtures and tools (cutting, measuring, auxiliary)

Organizational tooling: means for placing and storing fixtures, tools, auxiliary materials and documentation; industrial packaging for blanks and finished products; means of signaling and communication, maintenance of equipment and workplace

When organizing the workplace of the machine operator, the instructions for the operation of the equipment, safety precautions, sanitary norms and others. The space occupied by the workplace, as a rule, is determined by calculation. This space must be sufficient to allow workers to make all the necessary movements and movements during production operations. Also needed signaling and communication system , which ensures the exchange of information between the worker and the foreman, as well as intra-shop services

Important characteristics of the technological process and operation are the cycle, technological operation, tact and rhythm of release.

Cycle, beat and rhythm release

cycle technological operation is called the interval of calendar time from the beginning to the end of a periodically repeating technological operation, regardless of the number of simultaneously manufactured products.

Tact called the time interval through which the release of products or blanks of certain names, sizes and designs is periodically made.

Rhythm release refers to the number of products or blanks of certain names, sizes and designs, produced per unit of time.

It is desirable that the time spent on the execution of one operation be equal to the release cycle time or a multiple of it. Such a correction of the time spent on the operation is achieved by varying degrees of concentration of operations, the use of optimal processing modes, the reduction of auxiliary time due to multiple devices, automation of loading, transportation, the use of more high-performance equipment, parallel operation on the same type of backup machines, etc.

Questions for self-examination

1. Define a technological operation.

2. What is the reason for the division of the technological process into operations?

3. What is meant by technological route?

4. Explain the structure of the technological operation.

5. What is meant by the principle of constructing a technological process

A machine-building (machine-repair) enterprise performs various processes related to the manufacture (repair) of products.

Manufacturing process - this is a set of interrelated actions of people and tools of production necessary for a given enterprise to manufacture (repair) a product.

The production process includes not only the main processes associated with the transformation of raw materials to obtain finished products, but also auxiliary, for example, the production of tools, fixtures, equipment repair, as well as service processes (intra-factory transportation of materials and parts, warehouse operations, control, etc.), which provide the possibility of manufacturing products. A rational organization of the production process is impossible without a thorough technical training production.

Pre-production. This process includes the following:

1) design preparation for production (development of the product design and creation of drawings of the general assembly of the product, assembly elements and individual parts of products launched into production with the execution of relevant specifications and other types of design documentation);

2) technological preparation of production, i.e. a set of interrelated processes that ensure the technological readiness of enterprises (or enterprises) to produce products of a given quality level within established deadlines, output volumes and costs. Technological preparation of production includes: ensuring the manufacturability of the product design, development of technological processes, design and manufacture of technological equipment, process control technological preparation production;

3) scheduling the production process of manufacturing in a timely manner, in the required output volumes and costs.

A responsible and time-consuming part of the technical preparation of production is technological design, the labor intensity of which is 30 ... 40% (as a percentage of the total labor intensity of technical preparation) in small-scale production, 40 ...

The increase in the complexity of designing technological processes with an increase in product output is explained by the fact that in large-scale and mass production, the development of processes is carried out more carefully than in serial production (it increases in total volume, technological equipment becomes more complicated, documentation is developed in more detail).

The complexity of technological design in most cases significantly exceeds the complexity of designing machines.

Technological process(in a broad sense) is a part of the production process, containing actions to change and (or) determine the state of the object of labor.

In the conditions of machine-building production technological process is a part of the production process, which includes a consistent change in size, shape, appearance or internal properties of the subject of production and their control.

The objects of labor include blanks and products. The technological process can be attributed to the product, its component part or to the methods of processing, shaping and assembly, which are defined by GOST 3.1109–82. .P.

To ensure the most rational process of machining the workpiece, a machining plan is drawn up indicating which surfaces need to be machined, in what order and in what ways.

In this regard, the entire process of machining is divided into separate components: technological operations, installations, positions, transitions, moves, techniques.

Technological operation- this is a complete part of the technological process, performed at one workplace.

For example, turning a shaft, performed sequentially first at one end, and then after turning, i.e., rearranging the shaft in the centers, without removing it from the machine - at the other end, is one operation. If all the blanks (shafts) of a given batch are turned first at one end and then at the other, then this will be two operations.

Technological operation is the main element production planning and accounting. For the performance of operations set the norms of time and prices. Operations determine the complexity and cost of the process, required amount workers by qualifications and means of technological equipment.

In conditions automated production under operation is understood as a complete part of the technological process, performed continuously on an automatic line, which consists of several machines connected by automatically operating transport and loading devices.

In the conditions of flexible automated production, the continuity of execution can be disrupted by the direction of processed blanks to an intermediate warehouse in the periods between individual positions performed on different technological modules.

In addition to technological operations, in a number of cases (for example, in mass production, and especially when processing on automatic lines and in flexible technological complexes) are included auxiliary operations(transport, control, marking, chip removal, etc.)

that do not change the size, shape, appearance or properties of the workpiece, but are necessary for the implementation of technological operations.

setup- part of the technological operation performed with the unchanged fixing of the workpiece or the assembled assembly unit.

For example, turning a shaft while fixing in centers on a lathe is the first setting; turning the shaft after turning it and fixing it in the centers for processing the other end - the second setting. The same operation can be performed in one setup on a double-sided machine, which allows simultaneous turning on both sides.

When performing certain technological operations, an installed and fixed workpiece or an assembled assembly unit must occupy a number of successive positions relative to the working bodies of the equipment using rotary or moving devices, i.e., occupy different positions.

Position- a fixed position occupied by an invariably fixed workpiece or assembly unit to perform a certain part of the operation.

For example, in fig. 2.1 shows the milling of surfaces 1 and 2 in two positions; the workpiece is fixed on the rotary part 3 of fixture 4. Having processed surface 1 (first position), the workpiece, without unfastening, is rotated by 180 ° using the rotary part of the fixture, fixed with lock 5 and milling surface 2 (second position).

Rice. 2.1. Milling surfaces 1 and 2 in two positions

GOST 3.1109–82 defines the main elements of technological operations. The operation is divided into technological and auxiliary transitions.

Technological transition- this is a completed part of the technological operation, characterized by the constancy of the tool used and the surfaces formed by processing or connected during assembly.

For example, sequential turning with a cutter, first of one stage of the shaft, and then the other, will consist of two technological transitions; if you turn these steps simultaneously with two cutters (Fig. 2.2), then this will be turning in one transition. The processing of the same surface of the workpiece in the roughing and then finishing mode will consist of two technological transitions, since the cutting modes change.

Auxiliary transition- this is a completed part of a technological operation, consisting of human actions and (or) equipment, which are not accompanied by a change in the shape, size and surface roughness of the object of labor, but are necessary to complete the technological transition. Examples auxiliary transitions are: setting the workpiece before processing, turning the cutting head, changing tools, etc.

The transition consists of working and auxiliary moves.

working stroke- the completed part of the technological transition in the form of a single movement of the tool relative to the workpiece, accompanied by a change in the shape, size, surface roughness or properties of the workpiece. For each working stroke, one layer of material of a given thickness is removed with the same processing mode.

Auxiliary move- the completed part of the technological transition in the form of a single movement of the tool relative to the workpiece, not accompanied by a change in the shape, size, surface roughness or properties of the workpiece, but necessary to complete the working stroke. For example, the auxiliary move is the movement of the caliper lathe to its original position after turning.

Reception- this is a complete set of human actions used in the implementation of the transition or part of it and united by one purpose.