This scientific discipline arose in our state in the twenties of the last century in connection with the rapid growth of domestic mechanical engineering. Its development was facilitated by a wide range of Soviet scientists and engineers and production innovators. Its origin was based on the works of P.L. Chebysheva, I.A. Tim and other scientists, as well as in Soviet times, scientists - technologists: Sokolovsky, Kovan, Matalin, Balakshin, Novikov. The further formation and development of this subject is reflected in the works of I.I. Artobolevsky, V. I. Dikushin, A. P. Vladzievsky, L.N. Koshkina, G.A. Shaumyan and other domestic scientists.
Automation of production processes is one of the directions of development of the national economy. This is due to the fact that the automation of production opens up unlimited possibilities for the productivity of social labor. In addition to increasing labor productivity, it facilitates and radically changes the nature of labor, makes it creative, erases the difference between mental and physical labor.
Mechanization and automation makes it possible to improve the quality of products and the safety and utilization of equipment, and in some cases to intensify the operation of the equipment.
The problem of automation of production also raises socio-economic issues. V modern society automation of production is a means of obtaining maximum profit and a tool for fighting competitors. These and a number of other positive factors force us to pay serious attention to mechanization and automation.
The real economic effect obtained as a result of mechanization and automation largely depends on the specific conditions and for the solution of what production problems the means and methods of mechanization and automation are used. The mechanization and, especially, the automation of machine-building production requires significant capital expenditures. If the automation object is chosen successfully, these costs pay off quickly. In a short time, a high economic efficiency, and if you follow the path of "continuous" automation, then instead of saving you can get losses. Therefore, every mechanical engineer must have a clear understanding of technical capabilities means of mechanization and automation and be able to choose them correctly in each specific case with the greatest efficiency.
2. Basic concepts and definitions: mechanization, automation, single and complex mechanization and automation. Automation stages
Mechanization called the direction of development of production, in which the physical labor of the worker, associated with the implementation of the production process or its components, is transferred to the machine. Examples of mechanization are: the use of pneumatically and hydraulically driven chucks instead of the usual manual screw movement of the jaws with a wrench; displacement of the tailstock pins of lathes, quick approach of the caliper or machine table using electric, pneumatic or hydraulic supports. Mechanization makes the work of the worker easier. In this case, the actions aimed mainly at managing the production process remain with the worker. They are included in the cycle of the machine. Mechanization can be either partial or complete, or, as it is called, complex.
Partial mechanization- this is the mechanization of part of the movements necessary for the implementation of the production process: either the main movement, or auxiliary and positioning movements, or movements associated with the movement of products from one position to another.
Full or complex mechanization- mechanization of all basic, auxiliary, installation and transport movements that are carried out during the production process. With complex mechanization, the service personnel only carries out operational control of the production process, turning on and off the required mechanisms at the right times and controlling the mode and nature of their work.
Further development of mechanization leads to the automation of production. Those. automation is a direction of production development in which a person is freed not only from heavy manual labor, but also from the operational control of mechanisms or machines.
A distinction is made between partial and complex automation. Concept "Partial automation" associated with the implementation of automation of only one structural component from among all systems. For example, automation of individual elements of the general cycle of machine tools. Examples of this type of automation: equipping machines with loading devices, automating the supply and removal of the support, table, storage, as well as cleaning of shavings, etc. equipping with devices that partially automate the control and maintenance of machine tools. If we talk about the technological process as a whole, then, for example, one of ten operations is automated. Integrated automation is characterized by the transfer of parts processing, for example, from general-purpose machines to automatic lines, spans, workshops, as well as automatic factories. This direction is characterized by the continuity of processing, and the processing of parts, their control, transportation, accounting, storage, as well as cleaning of shavings, etc. are automated.
An example of a comprehensively automated production is the production of rolling bearings, where the production of bearings, starting from the blank and ending with control and packaging, is carried out by a set of automated equipment.
At integrated automation in addition to the previously listed advantages inherent in automation in general, it is possible continuous work in a single stream. The need for intermediate warehouses is eliminated, the duration of the production cycle is reduced, production planning and accounting of manufactured products are simplified. Here two principles are most fully and effectively combined - automation and continuity of the production process. Comprehensive automation of production is a radical and decisive means of increasing labor productivity and product quality, and reducing its cost.
The degree of automation of production processes can vary. Distinguish three stages of automation.
On the first stage automation, the worker is completely freed from physical labor (while the machine is running), including the labor of managing the production process. He carries out the initial adjustment of the machine, supervises the machine and corrects deviations from its normal operation. The first stage of automation is provided by an open-loop automatic control system (without feedback). An example is: automatic turret lathes, multi-spindle automatic lathes, and other machines and machines with cam mechanisms. The cam in this case provides a certain sequence, direction, magnitude and speed of movement of the executive bodies.
In second stage automation, closed-loop automatic control systems with feedbacks, which not only ensure the implementation of the set program, but also automatically, without the intervention of the worker, regulate and maintain normal operating conditions of the machine. The work of the worker in this case is reduced mainly to the initial adjustment of the machine. Take turning long shafts, for example. During turning, the wear of the cutter leads to an increase in the processing diameter, and if the active control device measures the processing diameter and, based on the results of these measurements, automatically introduces a correction to the machine setting (move the cutter in the desired direction), then we will have a CAP that maintains normal operating conditions.
Distinctive feature third stage automation is the ability of the control system to perform logical operations to select the optimal operating conditions for the machine. In addition to devices with feedback, such control systems have devices for solving logical problems (calculating machines), which allow to perform work under optimal conditions, taking into account the variability of external and internal modes of operation of the machine. Such machines are self-driving. For example, machines with a computer connected to it, which optimize machining in terms of minimum roughness, or provide maximum metal removal.
3. Concepts and definitions: automatic, semi-automatic, GPS, automatic line
Automatic machine is called a working machine (system of machines), in the implementation of the technological process on which, all elements of the working cycle (working and idle strokes) are performed automatically. The repetition of the cycle is carried out without human intervention. In the simplest machines, a person adjusts the machine and controls its operation. In more advanced systems, the quantity and quality of the product is automatically controlled, the tool is adjusted and changed, the original blanks and material are fed, chips are removed, etc.
Semi-automatic is called a working machine, the cycle of which at the end of the operation being performed is automatically interrupted. To resume the cycle (start the semiautomatic device), the intervention of a person is necessary, who sets and removes workpieces, starts up the machine and controls its operation, changes and adjusts the tool.
The terms and definitions of the types of flexible production systems are established by GOST 26228-84.
Flexible Manufacturing System (FPS)- a set or a separate unit technological equipment and systems for ensuring its functioning in automatic mode, which has the property of automated readjustment in the production of products of arbitrary nomenclature within the established limits of their characteristics.
SBSs are subdivided into the following levels by organizational structure:
· Flexible production module - the first level;
· Flexible automated line and flexible automated section - second level;
· Flexible automated workshop - the third level;
· Flexible automated plant - the fourth level;
According to the stages of automation, GPS are subdivided into the following stages:
· Flexible production complex - the first stage;
· Flexible automated production - the second stage.
If no indication of the level is required organizational structure production or stages of automation, then they use the general term "flexible production system".
Flexible Manufacturing Module (FPM) is a flexible production system consisting of a piece of technological equipment equipped with an automated device program control and by means of automation of the technological process; autonomously functioning, carrying out multiple cycles and having the ability to integrate into a higher-level system. A special case of a GPM is a robotic technological complex (RTK), provided that it can be integrated into a higher-level system. In the general case, the PMG includes storage devices, fixtures, satellites (pallets, loading and unloading devices, including industrial robots (PR), devices for tool replacement, waste disposal, automated control, including diagnostics, changeovers, etc.)
Flexible automated line (GAL)- GPS, consisting of several flexible production modules, combined automated system control, in which the technological equipment is located in the accepted sequence technological operations.
Flexible automated section (GAU)- FMS, consisting of several flexible production modules, united by an automated control system, operating along a technological route, which provides for the possibility of changing the sequence of using technological equipment.
Flexible automated workshop (GAC)- GPS, which is a set of flexible automated lines and (or) flexible automated sections, intended for the manufacture of a product of a given nomenclature.
Flexible Automated Plant (GAZ)- FMS, which is a set of flexible automated workshops, designed for the release of finished products in accordance with the main production plan.
The above definitions do not cover such terms as: automatic line, automatic section, workshop, plant. ENIMS offers the following definitions:
Automatic line (LA)- a set of technological equipment installed in the sequence of the technological process of processing, connected by automatic transport and equipped with automatic loading and unloading devices and common system management or several interconnected management systems.
The steps of automation are distinguished two types of GPS:
Flexible Manufacturing Facility (FPS) Is a flexible production system, consisting of several flexible production modules, united by an automated control system and an automated transport and warehouse system, functioning autonomously for a given time interval and having the ability to integrate into a system of a higher level of automation.
Flexible Automated Manufacturing (HAP)- FMS, consisting of one or several production complexes, united by an automated production control system and a transport and warehouse automated system, and carrying out an automated transition to the manufacture of new products.
Chip quality
(incoming control of 10-12% of microcircuits - 1990, Tomsk association "Kontur")
1. In what cases is automation ineffective in socio-economic terms?
3. Suggest the main sections of the business plan for the planned purchase and use in the metalworking workshop lathe with a CNC system.
4. What factors are decisive for improving the quality and reliability of products?
2. Automation in mechanical engineering,
CNC systems
A brief classification of production systems is as follows:
¨ production system Is a complex multilevel (hierarchical) system that converts initial semi-finished products, raw materials, materials into a final product corresponding to a public order;
more broadly: production- it is a combination of resources (raw materials, capital, labor and entrepreneurial ability) for the production of goods and services;
¨ the basis of any production - technological process (TP)- a certain interaction of tools of labor, service and transport systems;
¨ continuous TP: chemical, oil and gas production and processing, energy;
¨ discrete TP: mechanical engineering, cutting of materials;
¨ continuous-discrete TP: metallurgy, cement, mechanical engineering, etc.
We will take mechanical engineering as the basis of TP and corresponding automation systems. It was mechanical engineering (metal processing processes), along with the weaving industry, that first demanded automation. Mechanical engineering is widely developed in the Kama region. Let's take into account that automation systems in various industries
are carried out on a single technological basis, according to the same
principles.
Analysis technological processes in mechanical engineering shows that in the general cycle of organizing the production of a part, machine tool time takes on average no more than 5% (the rest is preparation for production, transportation, lying, etc.). In a hundred
overnight processing time is only about 30%
(the rest of the time is positioning, loading, measuring, idle time, etc.).
Efforts to intensify machining affect only a small portion of the overall balance of the finished product cycle. The same analysis shows that reducing non-production time losses is possible only on the basis of production integration, which allows, in principle, to bring machine time in the general production cycle up to 90%, machine time within the machine also up to 90%. This also means the integration of production, which would allow continuous three-shift operation of equipment, including low-population night shift.
In fig. 2.1 shows the balance of the time of use of production equipment, from which it follows that the most powerful reserve for increasing the utilization rate of equipment is three-shift work.
Practice has shown that, in principle, the correct idea - to link integration with a deserted technology - is quite difficult to implement, since it requires solving a whole range of complex problems. Among these problems is a sharp increase in the reliability of equipment and control systems based on MP-x systems.
Automation objects in mechanical engineering:
¨ machines: turning, milling, drilling and boring, grinding, multipurpose (machining center), gear-cutting, electro-erosion, etc .;
¨ machine tool periphery: robots, pallet accumulators, tool magazine blocks, etc.;
¨ transport systems: robocars, conveyors, etc.
¨ storage systems: automated warehouses with stacker cranes, picking stations, etc .;
¨ auxiliary systems: control and measuring machines, washing-drying stations, etc.
Rice. 2.1. Time balance of production use
equipment
Many separate microprocessor-based automation systems must be combined into a single - local area network. From the standpoint of productivity and flexibility, automation systems in mechanical engineering can be classified according to the level of flexibility and productivity (Fig. 2.2).
Rice. 2.2. Classification of automation systems in mechanical engineering:
x- the nomenclature of parts assigned to the equipment (number of batches);
y- the number of parts in the batch; 1
– universal machines with manual
management; 2
- CNC machines; 3
- multioperational machines;
4
- flexible production modules (FPM); 5
- flexible production sites (GPU); 6
- flexible lines, workshops; 7
- automatic lines
Table 2.1
Machine tool production in the main producing countries
| Manufacturer country | Machine tools | CNC machines /% value from all machines | Robots | |||||
| CMEA | – | – | – | |||||
| the USSR | 1,6/5,2 % | 8,9/24 % | 21,0/47 % | |||||
| China | – | – | – | |||||
| USA | 1,9/19 % | 8,9/34 % | 5,0/44 % | 27,1 | 9,4 | |||
| Japan | 1,5/7,8 % | 22,1/50 % | 35,3/70 % | 116,0 | 46,8 | |||
| FRG | 0,8/8,3 % | 4,7/28 % | 14/65 % | 12,4 | 4,8 |
It should be borne in mind that the number of machine tools in mechanical engineering is 1.5 times the number of machine operators. However, the demand for CNC machines in 1990 was not satisfied (Table 2.1).
Mechanization and automation of production processes is one of the main directions of technical progress. The purpose of mechanization and automation is to facilitate human labor, leaving the functions of maintenance and control to the person, increase labor productivity and improve the quality of manufactured products.
Rice. 3.2. Manipulator model ASh-NYU-1 used for mechanization of loading operations, including loading equipment
Mechanization- the direction of development of production, characterized by the use of machines and mechanisms that replace the muscular work of the worker (Fig. 3.2).
According to the degree of technical perfection, mechanization is divided into the following types:
partial and small mechanization, characterized by the use of the simplest mechanisms, most often mobile. Small-scale mechanization can cover parts of movements, leaving many types of work, operations, and processes unmechanized. Small-scale mechanization mechanisms can include carts, simple lifting devices, etc .;
complete, or complex mechanization, includes the mechanization of all basic, auxiliary, installation and transport operations. This type of mechanization
characterized by the use of rather sophisticated technological and material handling equipment.
The highest stage of mechanization is automation. Automation means the use of machines, devices, apparatus, devices that allow production processes to be carried out without the direct participation of a person, but only under his control. Automation of production processes is inevitably associated with the solution of management processes, which must also be automated. The branch of science and technology that solves control systems for automatic equipment is called automation. Automation is based on the management, control, collection and processing of information about an automatic process using technical means- special devices and devices. The automated control system (ACS) is based on the use of modern electronic computing technology and electronic mathematical methods in production management and is designed to improve its productivity.
Automation production processes are also divided into two parts:
partial automation, covers part of the operations performed, provided that the rest of the operations are performed by humans. As a rule, a direct impact on the product is automatically performed, i.e. processing, and the loading operations of the blanks and the repeated switching on of the equipment are performed by a person. Such equipment is called semi-automatic;
full or complex automation, characterized by the automatic execution of all operations, including loading. A person only fills the loading devices with blanks, turns on the machine, controls its actions, carrying out readjustment, tool change and waste disposal. Such equipment is called automatic. Depending on the volume of implementation of automatic equipment, automatic lines, an automatic section, a workshop and a plant differ.
As practice has shown, ordinary automation and complex automation schemes are effectively used only in large-scale and mass production. In a diversified production where frequent readjustments of the flow are required, conventional automation schemes are of little use. Equipment equipped with stationary automation systems does not allow switching over to control from manual mode... The usual automation scheme means the use of loading devices (skis, trays, bins, feeders, etc.) and processing equipment adapted to perform automatic operations. Processed products are removed using a device for receiving processed products (slips, trays, stores, etc.).
Auto operators and mechanical arms, long used in conventional automation schemes, served as prototypes for a new kind of automation. A new type of automation using industrial robots (PR) allows you to solve problems that cannot be solved using ordinary automation schemes. Industrial robots, as conceived by their developers, are intended to replace humans in hard and tedious jobs that are hazardous to health. They are based on modeling human motor and control functions.
Industrial robots solve complex processes of assembling products, welding, painting and other complex technological operations, as well as loading, transporting and storing parts. The new type of automation has a number of qualitatively distinguishing it from other types of properties that give PR significant advantages over ordinary schemes:
high handling properties, i.e. the ability to move parts along complex spatial paths;
own drive system;
program control system;
autonomy of PR, that is, their non-integration into technological equipment;
versatility, that is, the ability to move products of various types in space;
compatibility with a fairly large number of types of technological equipment;
adaptability to various types of work and products replacing each other;
the ability to disable the PR and switch to manual control of the equipment.
Depending on the participation of a person in the control processes of robots, they are divided into biotechnical, autonomous.
Biotechnical are remote copying robots controlled by a human. The robot can be controlled from the console using systems of handles, levers, keys, buttons, or by “putting on” special devices on the hands, feet or body of a person. These devices are used to reproduce human movements at a distance with the necessary increase in effort. These robots are called exoskeleton robots. Semi-automatic robots are also classified as biotech robots.
Autonomous robots work automatically using programmed control.
Over the relatively long history of the development of robotics, several generations of robots have already been created.
First generation robots(software robots) are characterized by a rigid program of actions and elementary feedback. These usually include industrial robots (PR). This system of robots is currently the most developed. PR of the first generation are divided into universal, target PR of the lifting and transport group, target robots of the production group. In addition, robots are divided into standard-size rows, into rows according to maximum productivity, according to the radius of service, according to the number of degrees of mobility, etc.
Second generation robots(sensed robots) have coordination of movement with perception. The control program for these robots is carried out using a computer.
TO third generation robots include robots with artificial intelligence. These robots create conditions for replacing a person in the field of skilled labor, have the ability to adapt in the production process. Robots of the third generation are able to understand language, can conduct a dialogue with a person, plan behavior, etc.
Robotic technological complexes (RTC) are being created by carrying out complex automation of technological processes of sections, workshops and factories. Robotic technological complex is a collection of technological equipment and industrial robots. RTK is located on a certain area and is intended for one or several operations in automatic mode. The equipment included in the RTC is divided into processing, service and control and management equipment. The processing equipment includes the main technological equipment, modernized to work with industrial robots. The service equipment contains a device for placing parts at the entrance to the RTK, interoperational transporting storage devices, devices for receiving processed products, as well as industrial robots (Fig. 3.3). The monitoring and control equipment ensures the operating mode of the RTK and the quality of the products.
Fig. 3.3. Floor-standing robot with a horizontal retractable arm and cantilever lifting mechanism PR-4
A rational reduction in the range of PR and an improvement in their adaptability (adaptability) contributes to an increase in the efficiency of the use of industrial robots. This is achieved by typing the PR. A comprehensive analysis of production, the grouping of robotization objects and the establishment of the types and main parameters of the PR are carried out. PR typification is the basis for the development of their unification, which should be aimed at ensuring the possibility of creating robots through aggregation. To ensure the principle of aggregation, standardization is carried out: 1) connecting dimensions of drives, transmission mechanisms and feedback sensors; 2) series of output parameters of drives (powers, speeds, etc.); 3) methods of communication of programmed control devices with executive and measuring devices.
The result of work on the unification of PR should be the creation of their optimal type and a system of aggregate-modular construction. An aggregate-modular system for constructing industrial robots is a set of methods and tools that ensure the construction of different standard sizes of PR kz of a limited number of unified units (modules and assemblies). It allows the use of a minimum number of commercially available functional units, which are selected from special industrial catalogs. This makes it possible in multi-product production to quickly rebuild robotic systems of machines for the release of new products. Flexible automated production (HAP) is based on the PR with modular construction.
Planning the introduction of mechanized and automated equipment is associated with the analysis of production. Analysis of production is reduced to identifying a number of conditions that contribute to the use of this equipment. Production involving heavy manual labor is not subject to analysis. The mechanization and automation of heavy manual labor is a paramount task and does not depend on the results of economic calculation.
The design of mechanization and automation of technological processes must begin with an analysis of the existing production. During the analysis, those features and specific differences, on the basis of which a particular type of equipment is selected, are clarified and specified. The pre-design stage of the development of mechanization and automation of production processes includes the solution of a number of issues.
1. Analysis of the product release program includes the study of: the annual product release program, stability and prospects of release; the level of unification and standardization; specialization and centralization of production; rhythm of production; freight turnover (freight turnover is the total mass of incoming and outgoing cargo - for loading operations). It must be remembered that the effectiveness of mechanization and automation of the process largely depends on the product release program. Mechanization and automation devices in mass and small-scale production will differ significantly.
2. The analysis of the technological process of manufacturing products subject to mechanization and automation includes: determining the suitability of the technological process for mechanization and automation; identification of shortcomings of the current technological process; determination of the complexity of the main and auxiliary operations;
comparison of current manufacturing modes with those recommended in reference books; analysis of the use of group technology; division of the technological process into classes.
The first main class includes processes that require orientation of the workpiece (part) and are characterized by the presence of a machined tool. These processes are inherent in the main nomenclature of products that are manufactured by cutting, pressure, or assembled, controlled, etc. The second main class includes processes that do not require orientation of the workpiece (part), they use a working environment instead of a machining tool. These include heat treatment, tumbling, washing, drying, etc.
The first transitional class includes processes that require orientation of the workpiece (part), but the tool is absent, and its role is played by the working environment; application of local coatings, control of hardness by magnetization, etc. The second transitional class includes processes that do not require orientation of the workpiece (part), but a processing tool is involved in them; production of parts by powder metallurgy, production of cermet and ceramic parts, etc.
3. Analysis of the design of the product, thus establishing the accuracy of the processing of the product and the completeness of the technical requirements for the manufactured part; the form, dimensions, materials, weight of the product are investigated and the suitability for one or another type of mechanization and automation is established.
4. Selection of information on various types of mechanization and automation. Before starting work, all techniques and technological schemes, as well as equipment, devices and means mastered by the industry, must be known. Before making a decision, a search is made for information on the production of similar products in the country and abroad.
5. Economic calculation of the effectiveness of the proposed mechanization and automation of production.
6. Development and approval of recommendations for changing the current production conditions. Recommendations are developed on the basis of the analysis carried out and they can be attributed to: unification, that is, reduction to the same standard size of products with similar designs; changing the sequence of technological operations or the use of a completely new progressive technological process; the use of a group technological process of products similar in design; application of a new type of product blank; clarification and, if necessary, changing the technical requirements of the drawing; changing the shape and size of the product; change in the material of the product.
7. Making a decision on the use of a certain principle of mechanization and automation and drawing up a technical assignment for development.
Fundamentally new technological processes require the creation of new technological equipment. Therefore, for their rapid implementation, an integrated development of technology and technological equipment is required.
The most important problem of the development of any modern production - automation of technological processes.
It is especially relevant for mechanical engineering, and here's why. First, the labor intensity of production is very high here. Here are just two examples: manufacturing steam turbine with a capacity of 500 thousand kilowatts, according to the norms, it takes 300 thousand hours, the creation of a sheet-rolling mill "2000" - 5.2 million hours. Secondly, out of 10 million mechanical engineering workers, about half are employed in manual labor.
Automation of mechanical engineering not only increases labor productivity, eliminates manual heavy and monotonous labor, but also increases the quality and reliability of manufactured products, improves equipment utilization, and shortens the production cycle.
What is the essence of the automation of any technological process? Automation must provide, without human intervention, the specified kinematics and parameters of the work process with the required sequence and accuracy.
Complexity of automation of mechanical engineering lies in the fact that the technology here is not continuous, but discrete and, moreover, extremely diverse. Mechanical engineering makes millions of different parts, and the manufacture of each part is associated with the implementation of a large number of technological operations. Casting, forging, welding, heat treatment, machining, hardening, coating, non-destructive testing, assembly, testing ... And each of these and many other technological processes not mentioned here also has different options depending on the materials used, the shape, sizes and serial production of parts, requirements for accuracy, performance, etc.
In mechanical engineering, mass production is only 12%, and even together with large-scale production - only 29%, and the share of serial and individual production accounts for 71%. This complicates the solution of the automation problem, since small-scale production requires a flexible, quickly reconfigurable system of automatic control of technological processes. The most expedient here is a two-hierarchical control system: directly each technological process is controlled by its own small computer, and the management of all production, taking into account the information received from them, is carried out by ordinary computers.
This path is very promising for the automation of mechanical engineering. But, of course, for its implementation, it is necessary to improve technological equipment and technological processes.
Until now, the patterns of many technological processes in mechanical engineering have not been sufficiently disclosed, and the operating parameters are regulated by empirical methods. In factories, due to the influence of the scale factor and other production conditions, insufficiently studied technology has to be worked out anew.
These problems are becoming more and more urgent, since the creation of new technology is associated with the complication of structures, the use of difficult-to-machine materials, increased requirements for quality, reliability, and operational characteristics.
In procurement production The most effective are continuous technological processes, for example, continuous casting of steel, rolling of billets, bending of spatial hollow billets from sheet and coiled strip. Continuous processes that are most conducive to automation provide the highest productivity and metal savings.
To improve the conditions for automation and mechanization assembly work, which are very laborious and in mass production are mainly carried out by hand, it is necessary to improve the design of parts and the layout of machines, to increase the accuracy of dimensional processing, to optimize the tolerances and dimensional chains of machines.
The automation of individual technological operations, of course, increases productivity and product quality. But the most effective is complex automation of sequentially connected technological operations. At the same time, inaccuracies of previous operations are eliminated, which can disrupt the operation of the machine at a subsequent operation, synchronization of the flow of technological operations is provided, eliminating downtime of the machines.
In small-scale production, preparation of production, design and manufacture of tooling, adjustment of equipment, installation, alignment of products, control, transportation and storage are associated with high labor and time costs. Therefore, the greatest effect in mechanical engineering is provided by integral automation: the main technological operations are automated together with auxiliary, control and transport operations.
The experience of using integrally automated production lines in production shows that labor productivity increases up to four times.
To complex automatic systems ensured high efficiency and excluded the labor of adjusters, management should be based on the principles of adaptation and adjustment of work processes. In this case, the parameters of the technological process, the state of the tool, the workpiece, its installation, coordination, processing accuracy should be controlled by sensors transmitting necessary information, on the basis of the processing of which the parameters of work processes are adjusted, tools are moved or replaced, etc.
Automatic flow lines must be equipped with automatically controlled technological equipment, vehicles, control devices, tilting, setting, shooting manipulators. In some cases, precise manipulators with great kinematic capabilities are required, and sometimes with tracking and automatic correction of operations. Such complex and automated manipulators, replacing far from simple manual labor, are usually called robots.
Practice shows that robots should be used not only for auxiliary operations, but also for the automation of complex, diverse technological operations, for example, spatial welding, assembly, cutting, stripping, packaging. Such operations require automatic tracking and spatial orientation, and robots must have adaptive control to automate them.
Also of great importance system automation technological preparation production, which should provide automatic design of technological processes, analysis of manufacturability of structures, determination of the range of equipment, tools, development of control programs, etc.
Automatic technology control not only excludes subjective errors inherent in manual labor, but also provides high stabilization of technological processes, adjustment of their parameters in connection with fluctuations in the size and properties of workpieces raw materials, changes in the state of equipment and tools.
Even in cases where the technological process is fully automated and its stability is ensured, the problem of automation of control is not completely eliminated. Therefore, it is necessary to develop automatic methods and means of analysis. chemical composition materials, non-destructive and metrological control, mechanical tests.
And in conclusion, I note that production automation greatly simplifies and gives the greatest economic effect with an increase in the serial production. That is why the most important condition for the expansion of automation is the specialization of production and the maximum unification of products. This principle of technical policy should be given great attention.
Corresponding member of the USSR Academy of Sciences N. Zorev, director of the Central Research Institute of Mechanical Engineering Technology (TsNIITMASH).
The current state and the nearest prospects of automation in mechanical engineering are associated, first of all, with the transition from the creation of individual machines and units to the development of systems of automatic machines, covering various stages of the production process - from procurement to assembly, with the optimization of technical solutions.
The center of gravity of developments is shifted from mass production to mass production with the widespread development of automation and mechanization of auxiliary processes, and not only automation of technological operations, but also of control functions.
Complex automation is based on continuous improvement technical means (from the simplest mechanisms to complex electronic systems; SPU, electronic computers and control machines, etc.); on the wide use of the generality of methods and means of automation at various stages of the production process, on the use of unification methods.
Development of automation on the present stage characterized by a shift in the center of gravity of developments from mass production to mass production, which constitutes the bulk of the machine-building industry (about 80% of all machine-building products are produced at serial and single production).
Other characteristic feature modern automation - the expansion of the arsenal of technical means and, as a result, the multivariate solution of problems of automation of production processes.
The strategy of complex automation of machine-building production as the basis of technical policy is determined by a number of aspects, including:
1) a correct understanding of the content and main focus of automation work;
2) an objective assessment in time of the prospects and expediency of the field of application of new methods and means of automation, their state and relationship with the known, traditional ones.
Let's consider these aspects in more detail. Automation of production is often interpreted as the process of replacing human functions with devices and control and monitoring systems, i.e. identified with the introduction of automation. At the same time, it is believed that technological processes, structures and machines remain basically the same. This is not true. The content of production is made up of technological processes, it is in them that all potential opportunities quality and quantity of products, production efficiency, and the management system is only a form of realizing these opportunities. Therefore, the automation of production in mechanical engineering is a complex design and technological task of creating new technology, such high-intensity technological processes and high-performance means of production that are inaccessible for direct human execution.
A modern automatic lathe is a complex of technological and structural-layout solutions, characterized by multi-position, simultaneous operation of dozens, and in automatic lines - hundreds of mechanisms and tools. The creation of such systems requires the solution of many problems, including the automation of transportation and loading of parts, changing their orientation, accumulating backlogs, turning and fixing parts, removing waste, etc. And only under these conditions can the use of automatic control be effective.
Automatically acting means of production are only promising when they perform production functions faster and better than humans.
The above does not diminish the value of "small" automation, i.e. equipping non-automated equipment with mechanisms for loading and clamping parts, devices for controlling the cycle, etc., especially when such means are typical. However, the automation process is not limited to this particular.
The problem of correct, objective assessment and wisely adopting the latest automation techniques and tools. Any technical innovation, no matter how promising it may be, goes through a number of stages: an idea - an experimental design (capable of only functioning) - a reliably working design - an economically efficient design. Each stage is characterized by the improvement of parameters, which can be reduced to the formula "performance - reliability - cost". And only when these parameters fit into the technical and economic tolerances, this innovation matures for industrial implementation. Therefore, in technical policy, both a delay in the development of a primary idea and the implementation of insufficiently matured solutions are unacceptable.
One of the fundamental issues of complex automation is the optimal combination of the latest methods and tools with traditional ones. In automatic machines and systems for mass production, the principles of differentiation and concentration of operations, their overlapping in time, are widely used, which is the basis of high productivity and efficiency. The overwhelming majority of modern CNC machines are single-spindle. Therefore, in conditions of stable operation, without changeovers, the productivity of multi-spindle modular semiautomatic machine tools is ten times higher than that of multi-operational semiautomatic machines, and the cost is lower. In pilot production, where the nomenclature of products is not repeated, a wide range of changeover of technological equipment is required, which can only be ensured by using a computer. In stable production, with a constant range of products, serial processing is carried out only because the scale of production does not allow loading each piece of equipment with the same products. Here, sections of universal semi-automatic machine tools with CNC or technological complexes controlled by a computer can be replaced by one readjustable multi-spindle modular semi-automatic machine, on which several parts are processed simultaneously by dozens of tools, its productivity is disproportionately higher than that of single-tool machines, and the changeover is much shorter.
Therefore, the release of single-spindle CNC machines with technological and layout diagrams inherited from manual production should be considered legitimate only at the early stages of their development. A massive transition to the use of multi-spindle and multi-position CNC machines is inevitable, starting with the simplest ones that perform parallel processing of several parts in one program. Systems with camshafts, cams and copiers, apparently for a long time to be predominant in control automation in mass production, despite the fact that their design has little electronics and no adaptation. Systems with PE, direct control from a computer, etc. are mobile, and therefore effective in the automation of serial, and in the future and single production. Their importance for mass production is not in replacing the existing technical solutions, but in their addition, in the implementation of previously impossible management functions. So, the use of an automated process control system with the functions of technical and statistical diagnostics of work automatic lines should become the basis for high-performance operation of lines, reducing their downtime for technical and organizational reasons.
