Design and technological features of modern radio-electronic equipment (REA). Assembly of electronic equipment
1. Design and technological features of modernradio electronic equipment (REA)
CEA is a set of elements designed to convert and process electromagnetic signals in the frequency range from infra-low to ultra-high (UHF) and combined into assembly units and devices. Elements designed for joint work in REA are distinguished by functional, physical, structural and technological features and types of connections. According to the design and technological features, REA elements are divided into discrete and integral, which are combined into assembly units that perform elementary actions (amplifier, generator, counter, etc.).
The design and technological requirements for electronic equipment include requirements for weight, overall dimensions, shape, etc. It is also essential here to provide heat removal, sealing, moisture protection, shock absorption, control, repair and protection of personnel from high voltages.
In the design and technological analysis of REA, much attention should be paid to its direct purpose and operating conditions. This is provided for by the general characteristics of radio engineering systems (RTS) and complexes (RTC), which include the analyzed equipment. The variety of functions performed by RTS and RTK and their operating conditions, the composition and characteristics of equipment carriers determine the requirements for its design and significantly affect the choice of technology for manufacturing elements and assembly units.
Large spatial scales (including continental, global and space scales) of modern RTCs lead to a spatial division of the equipment that makes up a single RTS within the RTC. At the same time, the equipment of the same RTS is often located on different types of objects: stationary points and mobile ground, surface and underwater objects, atmospheric, space, alien and even intergalactic aircraft; serviced and unattended objects, portable equipment, etc. All possible combinations of various effects on equipment should be taken into account when designing and optimizing technological processes (TP) of its manufacture. Since the capabilities and limitations of various technological systems (TS) for the manufacture of equipment strongly determine the features of its functioning under various disturbing influences, the designer and technologist are faced with the task of actively participating in all stages of the design and creation of RTK and RTS.
An objective trend in the improvement of REA designs is the constant growth of its complexity, which is explained by the expansion of the range of tasks to be solved while simultaneously increasing the requirements for the efficiency of its work. The complication of circuit and design solutions, together with a significant increase in the number of elements in electronic equipment, creates great difficulties in their production, especially in the assembly and installation of equipment, as well as adjustment and adjustment.
The design and technological features of REA include the functional-nodal design principle, manufacturability, minimum overall dimensions and mass indicators, maintainability, and protection from external influences. The conditions for ensuring the high reliability of REA and the specified characteristics determine the high requirements for the quality of the materials, equipment, and technological process used.
In addition, the production of REA should be cost-effective. When designing TP, it is necessary to provide for a reduction in the duration and labor intensity of the pre-production stage, capital costs, the number of complex and labor-intensive operations, the use of a minimum number of pieces of equipment, a maximum number of standard, unified and typical assembly units, functional units of REA. The essence of the functional-nodal principle of designing electronic equipment is to combine circuits into assembly units and their modular layout. Basic hardware designs have several levels of modularity:
1) Integrated circuits (IC);
2) Standard assembly elements (TES) or cells, printed circuit boards (PCB) of which
combine IS and electro-radio elements (ERE);
3) Blocks (panels) that combine cells into a structural unit;
4) Frame (structural unit - frame frame);
5) Rack (structural unit - rack frame).
At present, the main directions of REA development are microminiaturization of equipment, increasing the degree of integration, and an integrated approach to development, design, and production technology.
Microminiaturization is the micro-modular layout of elements using integrated and functional microelectronics. In case of micromodular arrangement of elements, discrete ERE are microminiaturized and assembled in the form of flat or spatial modules. This arrangement is used for volumetric placement of ICs with planar leads, which increases the reliability of both the elements themselves and their interconnections and provides conditions for mechanized production and assembly.
The basis of integrated microelectronics is the use of ICs and LSIs, the use of group manufacturing methods, machine methods for designing TC for manufacturing and control.
Functional electronics is based on the direct use of physical phenomena occurring in a solid body. Elements are created using distributed parameter environments. The main technological task in the implementation of functional microelectronics is to obtain media with desired properties.
An increase in the degree of integration, determined by the number of elements per unit area of the IC substrate or placed in one chip, changes the composition and structure of the structural levels of the electronic equipment layout - the complexity of the element base (first-level modules) increases, the number of levels decreases, the design complexity decreases and overall dimensions decrease devices.
2. Production and technological processes, their structure, types and types of organization
The production process is a set of all the actions of people and production tools necessary at a given enterprise for the manufacture or repair of manufactured REA products. The production process includes actions for the manufacture, assembly, quality control of manufactured products, storage and movement of its parts, semi-finished products and assembly units at all stages of manufacture; organization of supply and maintenance of workplaces, sites and workshops; management of all links of production, as well as a set of measures for the technological preparation of production.
The technological process is a part of the production process that contains purposeful actions to change and determine the state of the object of labor.
TP are built according to separate methods of their implementation (the processes of casting, mechanical and heat treatment, coatings, assembly, installation and control of REA) and are divided into operations. A technological operation is a completed part of the technological process, performed continuously at one workplace, on one or more simultaneously manufactured products by one or more workers. The condition of the continuity of the operation means the performance of the work provided for it without going to the manufacture or assembly of the product.
On the basis of operations, the complexity of manufacturing products is estimated and time standards and prices are established; the required number of workers, equipment, fixtures and tools, the cost of production is determined.
In addition to technological operations, the TP includes a number of auxiliary operations necessary for its implementation (transport, control, marking, etc.).
In turn, operations are divided into setups, positions, transitions, and techniques. The setup is a part of the technological operation, performed with the unchanged fixing of the workpieces to be processed or the assembly units- Position - part of the operation performed with the tool position unchanged relative to the part. Technological transition - a completed part of a technological operation, characterized by the constancy of the modes of the tools used and the surfaces formed by processing or connected during assembly. A technique is a complete set of human actions used when performing a transition or part of it and united by one purpose.
Microminiaturization of equipment, increasing its speed and accuracy of functional parameters require special attention to non-destructive methods of control and product quality control. The use of special materials and chemical technology makes the issue of protecting the environment and the people involved in the production of REA relevant.
When developing TP, it is necessary to take into account the principle of combining technical, economic and organizational tasks.
Depending on the range, regularity, stability and volume of production of products, modern production is divided into various types: single, serial and mass.
Single production is characterized by the breadth of the range and a small volume of output of products during the planned time interval. At unit production enterprises, the number of manufactured products and the sizes of operational batches of blanks and assembly units entering the workplace to perform technological operations are calculated in pieces and dozens of pieces; at workplaces, various technological operations are performed, which are repeated irregularly or not repeated at all; universal precision equipment is used; special tools and devices, as a rule, are not used; interchangeability of parts and assemblies in many cases is absent, fitting in place is widespread; the qualifications of the workers are very high, since the quality of the products produced largely depends on it; the low level of mechanization; the high cost of the equipment. ug Mass production is characterized by a narrow range and a large volume of products produced continuously for a long time. The coefficient of fixing the operation is 1, i.e., at each workplace, the execution of one constantly recurring operation is fixed. In this case, special high-performance equipment is used, which is arranged according to the flow line and, in many cases, is connected by transporting devices and conveyors to intermediate automatic control posts. Automatic lines and computer-controlled automated production systems are widely used. The average qualification of workers in modern mass production is lower than in single production, since relatively low-skilled worker-operators can work on tuned machines and automatic equipment.
Serial production is characterized by a limited range of products manufactured in periodically repeated batches and a relatively large output. Depending on the number of products in a batch or series and the coefficient of consolidation of operations, small-, medium- and large-scale production is distinguished.
The volume of output of serial-type enterprises ranges from tens to thousands of regularly repeating products. At the same time, universal and specialized equipment is used in production. Technological equipment is mainly universal, but special high-performance equipment can be used (especially in large-scale production), if this is justified by a technical and economic calculation. The average qualification of workers is higher than in mass production, but lower than in single production. Depending on the volume of production and the features of the products, complete interchangeability, incomplete, group interchangeability of assembly units is ensured, however, in some cases, dimensional compensation and fit in place are used in the assembly.
3. Technological preparation of REA production, its maintasks, regulations and rules of the organization
Technological preparation of production (TPP) should ensure the complete technological readiness of the enterprise for the production of REA products of the highest quality category in accordance with the specified technical and economic indicators.
The main tasks of planning the Chamber of Commerce and Industry: determining the composition, scope and timing of work by departments; identification of the optimal sequence and combination of work. Manufactured blocks, assembly units and parts of REA are distributed among production units, labor and material costs are determined, TP and equipment are designed. It performs the following tasks: -
1) Development of product design for manufacturability.
2) Forecasting the development of the level of technology, conducting laboratory research on new technological solutions;
3) Standardization of TP; development of standard TP;
4) Grouping TP.
5) Technological equipment.
6) Assessment of the level of technology (CDP departments together with the chief technologist
enterprises);
7) Organization and management of the CCI process.
8) Development of TP. CDP technology bureaus develop new and improve existing single TPs;
9) Design of special technological equipment.
10) Development of norms.
The modern CCI of complex radio-electronic products should be automated and considered as an integral part of CAD - a unified automation system for design, engineering and technological development.
4. Means of technological equipment for the production of REA, rulesselection and design
Means of technological equipment include: technological equipment, technological equipment, means of mechanization and automation of production processes.
Technological equipment is the tools of production, in which materials, means of influencing them, energy sources are placed to perform a certain part of the technological process.
Technological equipment is the tools of production added to the technological equipment to perform a certain part of the technological process.
Means of mechanization are tools of production in which the manual labor of a person is partially or completely replaced by machine labor, while maintaining human participation in the management of machines.
Automation tools are production tools in which control functions are transferred to machines and devices.
The composition of technological equipment and tooling is determined by the profile of the REA production workshops:
1) Blanking shops are equipped with equipment for producing blanks from standard profiles and sheets. Cutting of sheet materials and dissolution of rolls of materials is carried out mainly by guillotine and roller shears. Non-metallic materials with a thickness of more than 2.5 mm are cut on machine tools with circular saws, cutters, as well as abrasive and diamond cutting wheels;
2) Stamping shops are most often equipped with eccentric and crank presses, which belong to the category of universal equipment. In recent years, industrial robots have been successfully introduced into cold forging production. They make it possible to mechanize auxiliary operations (supply of strips, piece blanks, etc.), to turn universal presses into complex-automated ones;
3) The foundry shop, the shop for the manufacture of plastic parts have high-performance machines for casting and pressing, automatic presses, which make it possible to obtain blanks with minimal allowances for machining;
4) Mechanical workshops are mainly equipped with lathes and automatic machines, universal milling and drilling machines, grinding machines, etc. The manufacture of new generation equipment requires more precise machining. Improvement in the technology of cleaning the surface of parts and washing units has been going in recent years along the path of replacing explosive, flammable and toxic solvents with aqueous solutions of synthetic detergents and alkaline solutions;
5) Electroplating shops, depending on the economically viable level of mechanization, are equipped with various types of equipment: automatic lines that ensure the transfer of parts from one processing position to another and their holding in baths in accordance with a given processing program; PCS for electroplating;
6) Shops for the production of PP are equipped with universal equipment designed specifically for the production of this type of product. CNC equipment is used for the manufacture of photomasks and stencils, drilling mounting holes and milling PP;
7) In the coating shops, a high level of mechanization is achieved by organizing technological production lines. Currently, painting is one of the few types of processing where robots have found application as autonomous units (robots - painters) independently owning a working tool - a sprayer;
8) Assembly shops are equipped with both universal and special equipment and tooling. When assembling cells with ERE, having axial leads, they are glued into the tape according to the program and installed on the board. On CNC equipment, they install and solder ICs with planar leads, and also control the electrical circuits of the cells. Software control provides automation of wiring.
An important indicator of the operation of equipment, technological equipment is the degree of use of each machine and equipment individually and all together according to the developed process. Equipment and accessories should be selected according to performance.
Topic 2. TP design.
Initial data for the design of TP. EA design indicators.
As in the design of the design, when designing the TS, it is necessary to take into account the design indicators of the EA, operating conditions, limitations on the level of quality and economic parameters of production.
EA design indicators:
1. Design complexity: https://pandia.ru/text/78/545/images/image003_193.gif" width="113 height=49" height="49">, nji is the number of elements of the i-th type in the j-th device
3. EA volume..gif" width="164" height="25 src=">
5. Volume utilization factor (integration factor):
6. Cons. Power: https://pandia.ru/text/78/545/images/image008_67.gif" width="81" height="47">
8. The degree of tightness of the structure: the amount of gas that has expired from a given volume during the service life (or other defined period):
9. Wed time between failures, failure rate:
10. Probability of failure-free operation:
11. Coefficient of automation of design work:. (number of automated and non-automated works)
External factors that must be taken into account when designing TS
TP design procedure
Elementary assessment of product manufacturability
Manufacturability is a property of a design, at optimal costs of labor, time and money, to ensure the production of products in accordance with the design documentation with the fulfillment of requirements within the established limits.
Manufacturability is manifested in the design, technology and operation. Evaluation of manufacturability can be quantitative and qualitative. Qualitative assessment is based on the employee's experience and is subjective. Quantitative evaluation is carried out according to design and technological indicators.
Methods for evaluating manufacturability - qualitative and quantitative - are developed in accordance with the typical designs of parts, assemblies, machines, devices, etc.
Manufacturability indicators are divided into basic and additional. The main indicators include the following:
1) The cost of manufacturing the product: C=CM+SZP+CCR.
2) The complexity of manufacturing the product: https://pandia.ru/text/78/545/images/image014_34.gif" width="77" height="52 src=">.
4) The coefficient of the level of labor intensity of manufacturing the product: https://pandia.ru/text/78/545/images/image016_31.gif" width="108" height="55 src=">, where:
Nms is the total number of microcircuits;
Nere is the total number of ERE.
2) Chip repetition rate 
, Where:
Ntms - the number of standard sizes of microcircuits;
3) Coefficient of unification (applicability) of the design https://pandia.ru/text/78/545/images/image023_19.gif" width="148 height=49" height="49">, where:
Tn is the normal value of the coefficient;
Tf is its actual value;
DT is the equivalent.
If this formula results in a score value greater than 5, it is equated to 5, if less than zero - to zero.
Table 1 - An example of assessing the manufacturability of a REA product
Index | ||||
TP documentation. The concept of ESTD. Types of technological documents.
Rules for choosing a set of TD for a given TP.
Types of documents for various technological processes are established by GOST 3.1102-81 "Development stages and types of documents" and GOST 3.1119-83 "General requirements for the completeness and execution of sets of documents for single technological processes", and their completeness depends on the type of description of the technological process. Samples and rules for filling out TD are given in GOST 3.1103-82 and 3.1118-83.
The type of description of the technological process is determined by the type and nature of production, as well as the stage of development. There are the following types of description of technological processes:
route
route-operational
operational
The basis for the development is the TOR, which sets out: purpose, scope, technical, operational and economic requirements, storage and transportation conditions, rules for testing and acceptance of samples.
On the basis of the TOR is being developed Technical Proposal. For this, an analysis of existing technical solutions, patent research, the study of possible options for creating EA, the choice of an opto solution, the layout of individual nodes are carried out.
On the stage preliminary design K and T study of the selected var-ta, production of the actual sample / series, tests, revision of the design documentation, which are assigned the letters E, are being worked out, the main issues of the production technology are being worked out.
On the stage those. designer making final decisions on the design and technology of the publishing house, resolving a complete set of TD.
For TD, the concept is introduced lettering. The letter of the document reflects the stage of development of the TD. The lettering of the complete set of technological documentation is determined by the lowest of the letters indicated in the documents included in the set.
TD development stages:
· Preliminary project. Development of technological documentation intended for the manufacture and testing of a mock-up of the product and (or) its components with the assignment of the letter "P", based on the design documentation made at the stages "Draft design" and "Technical design".
· Development of documentation for a prototype or batch. Development of technological documentation intended for the manufacture and testing of a prototype (pilot batch), without assigning a letter, based on design documentation that does not have a letter. Correction and development of TD based on the results of manufacturing and preliminary tests of the OO / OP with the assignment of the letter “O” based on the design documentation with the letter “O”. Correction and development of technological documentation based on the results of manufacturing and acceptance tests of a prototype (pilot batch) and on the results of adjustment of design documentation with the assignment of technological documentation of the letter “O1” on the basis of design documentation with the letter “O1”. Correction and development of TD based on the results of re-production and acceptance tests of OO / OP and based on the results of updating the design documentation with the assignment of the technological documentation of the letter “O2” based on the design documentation with the letter “O2”.
· Development of documentation for serial or mass production. Development of technological documentation intended for the manufacture and testing of products of serial (mass) production, with the assignment of the letter “A” (“B”), based on design documentation with the letter “A” or “B”.
Document types:
Depending on the purpose, technological documents (hereinafter referred to as documents) are divided into main and auxiliary.
The main documents include:
fully and unambiguously defining the technological process (operation) of manufacturing or repairing the product (component parts of the product).
Ancillary documents include documents used in the development, implementation and operation of technological processes and operations, for example, an order card for the design of technological equipment, an act of implementing a technological process, etc.
The main technological documents are divided into documents of general and special purpose.
General-purpose documents include technological documents used individually or in sets of documents for technological processes (operations), regardless of the technological methods used for the manufacture or repair of products (component parts of products), for example, a sketch map, technological instructions.
Special purpose documents include documents used in the description of technological processes and operations, depending on the type and type of production and the technological methods used for the manufacture or repair of products (component parts of products), for example, a route map, a process map, a map of a typical (group) technological process , a list of products (parts, assembly units) for a typical (group) technological process (operation), an operating card, etc.
Main TD:
General purpose documents:
· Title page (TL). It is intended for registration of a set (s) of technological documentation for the manufacture or repair of a product; a set (s) of technological documents for technological processes for the manufacture or repair of the product (component parts of the product); certain types of technological documents. It is the first sheet of the set (s) of technological documents.
· Sketch Map (SM). A graphic document containing sketches, diagrams and tables and intended to explain the execution of a technological process, operation or transition in the manufacture or repair of a product (component parts of a product), including control and movement.
· Technological instruction (TI). It is intended to describe technological processes, methods and techniques that are repeated in the manufacture or repair of products (component parts of products), the rules for operating technological equipment. It is used to reduce the volume of technological documentation being developed
Some special purpose documents:
· Route map (MK) The document is intended for a route or route-operational description of a technological process or an indication of the full scope of technological operations in the operational description of the manufacture or repair of a product (component parts of a product), including control and movement through all operations of various technological methods in a technological sequence, indicating data on equipment, technological equipment, material standards and labor costs. It is a mandatory document. It is allowed to develop MC for certain types of work. It is allowed to use the MC in conjunction with the corresponding technological information card, instead of the technological process card, with an operational description in the MC of all operations and a full indication of the necessary technological modes in the column “Name and content of the operation”. It is allowed to use the appropriate process flow chart instead of MK.
· Process flow chart (CTP). The document is intended for an operational description of the technological process of manufacturing or repairing a product (component parts of a product) in a technological sequence for all operations of one type of shaping, processing, assembly or repair, indicating transitions, technological modes and data on technological equipment, material and labor costs.
· Operating card (OK). The document is intended to describe a technological operation, indicating the sequential execution of transitions, data on technological equipment, modes and labor costs. It is used in the development of single technological processes.
· Technological information card (KTI). The document is intended to indicate additional information required when performing individual operations (technological processes).
· Picking card (QC). The document is intended to indicate data on parts, assembly units and materials included in the kit of the assembled product, and is used in the development of assembly processes. It is allowed to use QC to indicate data on auxiliary materials in other technological processes.
· Statement of operations (VOP). The document is intended for an operational description of technological operations of one type of shaping, processing, assembly and repair of a product in a technological sequence, indicating transitions, technological modes and data on technological equipment and time standards. Used in conjunction with MK or KTP
· Equipment list (VO). The document is intended to indicate the technological equipment used when performing the technological process of manufacturing or repairing the product (component parts of the product)
· List of equipment (VOB). The document is intended to indicate the equipment used, necessary for the manufacture or repair of the product (component parts of the product)
· Bill of materials (BM). The document is intended to indicate data on the detailed consumption rates of materials, blanks, the technological route of the manufactured or repaired product (component parts of the product). It is used to solve problems on the rationing of materials.
· Statement of technological documents (VTD). The document is intended to indicate the complete set of documents required for the manufacture or repair of products (component parts of products), and is used when transferring a set of documents from one enterprise to another.
The described documents are used when documenting single TS. For typical (group) technological processes, a number of documents are provided that determine the nature of the links in the manufacture of specific types of products.
A number of documents are also provided, where information is presented in a more detailed form (rates of consumption of materials, labor costs, etc.).
Applicability of documents - give table. From GOST 3.1119-83
Electrical connections
It is known that more than 50% of all REA failures occur due to poor-quality electrical connections. The complexity of modern REA leads to a large number of connections, which poses the problem of minimizing their volume and influence on product parameters. This causes the requirements for e. With. requirements:
Reliability and durability
Low and stable ohmic resistance
Mechanical strength
Minimum parameters for the contact creation process (temperature, pressure, duration)
Possibility of connection of various combinations of materials and standard sizes
Resistant to thermal cycling
The contact zone should not form compounds that cause degradation of the connection
Simplicity and reliability of connection quality control
· Manufacturability of the process of creating e. With.
Diffusion" href="/text/category/diffuziya/" rel="bookmark">diffusion of surface layers. The latter is achieved due to factors such as heating, deformation, ultrasonic vibrations, etc., or combinations of these factors.
Advantages (compared to soldering):
High mechanical strength of the connection
No foreign material in contact area
Possibility to reduce the distance between contacts
Flaws:
Limited material combinations
Increase in contact resistance during the formation of intermetallic compounds
Lack of group welding technologies
Difficulty of repair
Connections based on the deformation of contacted parts are made without heating. Under the influence of mechanical stresses, oxide films are destroyed and a reliable vacuum-tight connection is formed.
Advantages:
Mechanical strength
· Low cost
Ease of mechanization
Flaws:
Interference that increases with voltage
The connection with conductive adhesives and pastes is used in cases where other methods are impossible: in hard-to-reach places, during repair work, etc. It does not change the structure of the materials being joined, but the contact resistance is high, and the heat resistance and reliability are low.
The choice of method e. With. is determined by the design of the contact assembly, the material of the parts, the requirements for quality, productivity and manufacturability.
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(carry out the wave separately)
Printed circuit boards
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Assembly of modules on printed circuit boards
PP are the main elements that form the modules. They place ERE, MS, El-you switching, etc. The number of MS and ERE on the PP is in most cases tens to hundreds of pieces.
Mounting types:
Pin (axial)
Planar
Surface
Installation methods depending on the type of production:
· Mechanized
· Semi-automatic
Automatic
The main operations, regardless of the type of production:
Entrance control
· Complete set of elements
Preparation of elements for installation
Installing elements on the board and fixing
Protection and control of the finished module
Input control
Input control - TP for checking the ERE, IS and PP arriving at the consumer plant in terms of parameters that determine their performance and reliability before use in production. The need is caused by the unreliability of the output control of the manufacturer, the effects during transportation and storage. The costs are much less than when testing and repairing assembled boards, blocks and equipment in general.
All components are subjected to tests, the scope and conditions of which are set for each type of product, depending on the actual quality of this product, determined by the analysis of statistics. Data and requirements for the finished product.
Possible VK operations:
Appearance check
Selective control of overall, mounting and connecting dimensions
Checking technological properties (solderability, weldability)
Electric thermal training (a week at an increased temperature of the working environment)
Checking static electrical parameters at different t-re
Verification of dynamic parameters under normal climatic conditions
Functional control at normal and elevated temperatures
ERE equipment
For automated picking, programmable storage stores are used, where cells with elements are located on shelves attached to the conveyor. Special windows are used to load and unload elements, the conveyor movement is controlled from the terminals at the windows. To pick up elements, lamp signaling is used in the case of manual picking and programmable coordinate tables when using manipulators. At the same time, ERE are placed in a matrix-type container.
For the tables of the installer, conveyors or carousels are used to feed the elements.
For assembly machines, the elements are installed in a tape or in cassettes with a certain step.
For piece ERE, vibrobunkers are used, where, due to different weight and size characteristics of ERE, it is possible to select the sequence of their output by the oscillation frequency.
Preparing for installation
Includes:
· Straightening
· Molding
cropping
· Tinning
Methods: stamping according to a given shape with simultaneous trimming, carousel machines for sequential operations.
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ERE fixation
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REA adjustment and testing
Adjusting and tuning operations (RNO)
RNO- a set of works to bring the EA parameters to the values corresponding to the requirements of technical conditions (TS) and normals. Designed to eliminate errors introduced in the manufacturing and assembly processes, as well as the non-ideal characteristics of finished ERE. Carrying out RNO allows you to significantly reduce the requirements for the accuracy of technological processes and applied ERE, and thereby reduce the cost of the finished product.
The work performed in RNO may include setting up resonant systems, pairing the electrical, kinematic parameters of individual units and all equipment as a whole, setting the modes of individual blocks, fitting individual elements, etc. The nature and volume of RNO is determined by the type and volume of production, as well as TP equipment.
When conducting RNO, the task of minimizing labor and time costs is important. Solution methods:
· Development of RNO implementation methodology
RNO automation
Special circuit and design solutions
Distinguish between operational and factory adjustment. In pilot production, the adjustment process may be accompanied by a partial change in the scheme and design of the sample. In serial and mass production, RNOs are divided into simple operations that provide for obtaining one or more parameters related to each other. Adjustment is carried out on specialized installations.
EA adjustment methods:
・Measurements
Comparison with a sample or standard (electrical copying method)
EA adjustment steps:
Shaking on the vibrating stand to detect loose connections and remove foreign objects
Checking the correct installation according to special maps or tables
Checking the operating modes of the IC and p / p devices for electro-calibration cards
Checking the functioning of the device as a whole
Adjustment
The applicable documentation is determined by the type of production and the complexity of the product. In a single production, it is possible to carry out adjustment according to the electrical circuit, taking into account the requirements of technical specifications. In serial and mass production, most often a special technological instruction is created with a description of the necessary equipment, methods and sequence of adjustment. For fairly simple devices, the use of a technological map is acceptable.
REA tests
EA tests - experimental determination of the quantitative and qualitative characteristics of products during their operation under various influences. In this case, both the tested products themselves and the effects can be simulated. The objectives of the tests are different at different stages of the design and manufacture of EA. Basic goals:
selection of optimal design and technological solutions for the creation of new products;
· fine-tuning products to the required level of quality;
· an objective assessment of the quality of products when they are put into production, during production and during maintenance;
Guaranteeing the quality of products in international trade.
Testing is an effective means of improving quality by identifying:
Deficiencies in the design and manufacturing technology of EA, leading to a failure to perform the specified functions under operating conditions;
Deviations from the chosen design or accepted technology allowed in production;
· latent random defects in materials and structural elements that cannot be detected by existing methods of technical control;
· reserves to improve the quality and reliability of the developed constructive and technological version of the product.
Based on the results of testing products in production, the EA developer determines the reasons for the decline in quality. If these reasons cannot be established, the methods and means of control of products and technological process of their manufacture are improved.
To improve the quality of the produced EA at the final operations of the technological process of their manufacture, preliminary tests are carried out to identify products with hidden defects. The modes of these tests are chosen such that they provide failures of products containing latent defects, and at the same time do not exhaust the resource of those products that do not contain defects that cause failures during operation. These tests are often called technological training(thermocurrent training, electric training, thermal cycle training, etc.).
Documentation:
Test program. Set out:
Information about the test object
Parameters to be measured
Criteria for acceptance and failure
Scope and method of testing
Necessary work
Test Method:
Method, means and test conditions
Algorithms for performing operations to determine individual characteristics of an object
Forms of presentation of information
Method for assessing the accuracy and reliability of the results
· HSE requirements
The program and methods of testing are determined by the specific type and purpose of the EA, as well as by the operating conditions. For quality control and acceptance of products, the main categories of control tests specified in the TS are established: acceptance, periodic and standard.
Each category of tests may include several types of tests (electrical, mechanical, climatic, reliability, etc.) and types of control (visual, instrumental, etc.). Depending on the characteristics of the operation and purpose of products, as well as the specifics of their production, some types of tests are divided into separate categories of tests (for reliability - reliability, durability, shelf life, etc.). Types of tests and control, the sequence of carrying out, the parameters to be checked and their values are established in the specifications (standards, programs, methods, etc.).
During the tests, continuous or selective control is used according to the specifications and the control plan. The test results are considered negative if the product is found to be inconsistent with at least one specification requirement for the test category being carried out. The applied means of testing, measurement and control, as well as measurement procedures must comply with the requirements of metrological support. It is forbidden to use test tools that have not passed metrological certification.
Acceptance tests (PSI). These tests are carried out to control the product for compliance with the requirements of the specifications established for this category of tests. On PSI products are presented by the piece. Tests and acceptance are carried out by a representative of the customer in the presence of a representative of the technical control department (QCD) of the manufacturer in the scope and sequence provided for in the technical specifications for the product. The manufacturer notifies the representative of the customer about the readiness of the product for the PSI by a notice drawn up in the prescribed manner. The notification shall be accompanied by protocols of technological training and bearer tests performed in the form adopted by the manufacturer.
The composition and sequence of testing can be changed by agreement with the customer's representative. Accepted are products that have passed the test, completed and packaged in accordance with the specifications.
Periodic testing. Such tests are carried out with the aim of: periodic quality control of products; control of TP stability in the period between tests; confirmation of the possibility of continuing the manufacture of products according to the current design and technological documentation, specifications and acceptance. The calendar dates for testing are set in a schedule drawn up by the manufacturer with the participation of a representative of the customer. Periodic tests are carried out on one product per year. The test results are documented in an act, to which a protocol is attached, made in the form adopted by the manufacturer.
The composition and sequence of testing can be changed by agreement with the customer's representative.
If the product has passed the periodic tests, then its production continues until the next test period. If the product has not passed the periodic tests, then the acceptance of the products and the shipment of the accepted products are suspended until the causes of defects are eliminated and positive results of repeated tests are obtained.
Type tests carried out for discontinuous production products (single and small-scale discontinuous production) to assess the effectiveness and feasibility of proposed changes to the product or its manufacturing technology, which can change the technical and other characteristics of the product and its operation. Tests are carried out on products in which the proposed changes have been made, according to the program and methodology of the necessary tests from the acceptance and periodic tests.
If the effectiveness and expediency of the proposed changes are confirmed by the results of type tests, then they are included in the relevant documentation for the product in accordance with the requirements of the State Standards.
Bearer tests (PI). Before presenting products for testing and acceptance to a representative of the customer, the quality control department conducts presentation tests of finished products. Such tests are carried out in order to control products for compliance with the requirements of technical specifications and readiness for presentation to the customer. As a rule, they are carried out in the amount of at least acceptance tests, but control plans and standards for the parameters being checked can be set more stringent.
Main test documents:
Tests are selected based on the required parameters, economic indicators of test methods.
Tests for the effects of external factors are carried out by the methods specified in ST IEC 68-2.
TECHNICAL REQUIREMENTS FOR INSTALLATION
CONNECTORS A and RP
GOST 23588-79
IPK STANDARDS PUBLISHING HOUSE
Introduction date 01.07.80
1. This standard applies to electrical installation (hereinafter referred to as installation) of radio-electronic equipment and devices.
The standard establishes requirements for the installation of instrumental parts of electrical connectors A and RP.
The terms used in the standard correspond to GOST 21962 and GOST 14312.
2. The installation of connectors A and RP must be carried out in accordance with the requirements of this standard, regulatory documentation (RD), design and technological documentation approved in the prescribed manner.
3. The installation of the same type of connectors in the product must be identical.
4. To ensure the identity of the installation of connectors, a control sample of the installation, approved in the prescribed manner, should be made.
For prototypes of products, control samples of installation are not installed.
5. Requirements for the installation of instrument parts of connectors A and RP, established by this standard, must be specified in the design documentation.
Example: "Technical requirements for electrical installation of instrument parts of connectors A in accordance with GOST 23588".
6. Additional requirements for the installation of connectors that do not reduce its quality should be indicated in the design and technological documentation.
7. The cross-sectional area of the wires supplied to the contact parts (hereinafter referred to as the contact) of connectors A and RP should not exceed the cross-sectional area established in the technical specifications for connectors of specific types.
8. If it is necessary to solder several wires of a smaller section into one connector contact hole, then the cores of all wires must be twisted together, and the total diameter of the tinned wires must be less than the diameter of the corresponding hole in the connector contact.
9. The length of the soldered part of the wire entering the hole of the mounting part of the contact must be equal to the length of the mounting part of the internal cavity of the contact.
10. The termination of one wire with a cross section of up to 0.75 mm 2 into the contact of connector A must comply with drawing. 1, 2. In this case, do not put tubes on the fastening part of connectors A.
11. The termination of one or more wires with a total cross-sectional area from 0.75 to 2.50 mm 2 into the contact of connector A without a jumper must comply with drawing. 3, with a jumper - hell. 4.
12. The termination of wires into the contact of the RP connector must comply with drawing. 5, 6.
13. With an inner diameter of the contact shank over 2.0 mm, as well as for wires with polyethylene insulation, the stripping of the wire from the insulation should not be more than 3.0 mm.
14. The spare contacts in the connector are soldered with pieces of wire of one of the brands used for installation. Recommended wire length 40 - 100 mm.
1 - solder; 2 - lived; 3 - insulating tube; 4 - the wire; 5 - connector type RP-15
1 - the wire; 2 - lived; 3 - connector contact type RP-14
The need for soldering backup contacts is determined by the developer of technical documentation.
(Revised edition, Rev. No. 1).
15. Reserve contacts should not be soldered in connectors filled with sealant or operating for a short time (up to 15 minutes of single action) when exposed to vibration that meets the specifications for the connectors.
16. The ends of the reserve wires should be terminated in a common bundle in accordance with drawing. 7 - 10.
17. When mounting connectors, it is not allowed to use wires whose outer diameter for insulation, together with an insulating tube put on the wire, is greater than the distance between the axes of the contacts in the connector.
18. Wires embedded in connectors must be fixed at the connector body.
When mounting a RP-14 connector, each wire soldered into a contact should be fixed separately.
1 - tourniquet; 2 - insulating tape; 3 - reserve wires
1 - tourniquet; 2 - thread bandage; 3 - conduit; 4 - the wire
1 - the wire; 2 - thread bandage
1 - the wire; 2 - conduit
19. Straightening of wires after soldering is not allowed.
20. The wires of the harness must be connected along the rows of connector contacts in accordance with Fig. 11, 12, while crossing individual wires is allowed.
21. Jumpers in the connector, made with a mounting wire, should be looped into the bundle. Jumper loops should be arranged in steps. The length of the jumper loop in this case should not exceed 100 mm from the harness attachment at the connector.
The need to introduce loop jumpers into the bundle is determined by the developer of the design documentation.
22. With a large number of jumpers in the connector and a small number of circuits (up to 10 circuits), the jumpers should be inserted stepwise into the trunk of the bundle. The length of the jumper part in the trunk of the bundle must not exceed 100 mm.
23. The wires to the connector contacts must fit freely without tension, be straightened and have a margin in length for one soldering. When filling with a compound, the stock may be absent.
24. Stripping wires from insulation should be done to a length of 10 - 12 mm.
25. The cores of the wires should be twisted in the direction of the layer, irradiated and cut to size.
26. When embedding shielded wires cut in accordance with GOST 23585 into connectors, it is not allowed that the braid of the shields of these wires enter the insulating tubes put on the connector contacts.
27. Before soldering, the ends of the bundle wires should be passed through the hole of a special template (simulator of the contact field of the connector) to prevent the wires from crossing in the installation area.
28. Before soldering into the contacts of the connectors, the wires must be put on insulating tubes with a diameter that ensures their tight fit after soldering on the contact and (or) wire (wires).
If the connectors are to be potted or wrapped, there are two options:
a) with tubes;
b) without tubes.
(Revised edition, Rev. No. 2).
29. The length of the insulating tubes put on the contacts of the connectors should be 10 - 12 mm.
1 - connector; 2 - tourniquet
1 - conduit
30. During installation, the connector should be installed in a position that prevents flux from flowing into the connector, so that the cut-off part of the contacts is directed towards the electrician.
31. Soldering wires to the connector should be done in rows of contacts, starting from the bottom row in the direction from left to right.
32. In the disassembled state, the contact side of the connector must be closed with a technological cover.
33. When soldering wire cores to connectors, the choice of soldering iron power should be made in accordance with the instructions of the ND for connectors.
34. The time for soldering the wire cores into the contacts of the connectors is set in accordance with the instructions of the ND for the connectors.
33, 34. (Revised edition, Rev. No. 2).
35. The time of soldering the wire into the contact of the connector type RP-14 should not be more than 3 s.
36. Soldering in RP connectors should be done in such a way that the contour of the soldered wire strands is visible under the solder.
37. The soldered surface of the mounting joints must be shiny or matte without dark spots, cracks, shells, sharp protrusions and foreign inclusions. The solder should flood the junction from all sides, filling the gaps and gaps between the cores of the wires and the contacts, with a slight influx of solder on the outer surface of the contact.
The amount of solder required for soldering should be kept to a minimum.
The quality of soldering in connectors should be checked after soldering each row of contacts.
38. During installation, the protective coating of the connector parts, as well as the coating of the parts on which the connectors are mounted, should not be violated.
39. Upon completion of the installation, the connectors must be cleaned from the remnants of installation materials and contamination.
The requirement does not apply to installation using fluxes that do not allow cleaning.
40. The quality of soldering connectors is checked during interoperational control before putting on the contacts of the insulating tubes.
41. After mounting and checking the quality of the soldering, the insulating tubes must be pushed over the contacts until they stop against the connector insulator.
42. Continuity of connectors should be made using a technological mating part.
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Ministry of General Engineering of the USSR
2. APPROVED AND INTRODUCED BY Decree of the USSR State Committee for Standards dated April 26, 1979 No. 1534
3. REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS
Installation of electrical radio-electronic
equipment and devices
GENERAL REQUIREMENTS FOR VOLUME
INSTALLATION OF ELECTRONIC PRODUCTS
ENGINEERING AND ELECTRICAL
INTERSTATE COUNCIL
ON STANDARDIZATION, METROLOGY AND CERTIFICATION
Minsk
Foreword
1 DEVELOPED by the Research Technological Institute of Instrumentation of the Minmashprom of Ukraine
INTRODUCED by the State Committee of Ukraine for Standardization, Metrology and Certification
2 ADOPTED by the Interstate Council for Standardization, Metrology and Certification (Minutes No. 9 dated April 12, 1996)
State name | Name of the national standardization body |
The Republic of Azerbaijan | Azgosstandart |
Republic of Armenia | Armstate standard |
Republic of Belarus | State Standard of the Republic of Belarus |
The Republic of Kazakhstan | State Standard of the Republic of Kazakhstan |
Republic of Kyrgyzstan | Kyrgyzstandart |
The Republic of Moldova | Moldovastandard |
Russian Federation | Gosstandart of Russia |
The Republic of Tajikistan | Tajik State Standard |
Turkmenistan | Main State Inspectorate "Turkmenstandartlary" |
State Standard of Ukraine |
3 By the Decree of the State Committee of the Russian Federation for Standardization and Metrology dated February 15, 2001, No. 71-st, the interstate standard GOST 23592-96 was put into effect directly as the state standard of the Russian Federation from July 1, 2001.
4 INSTEAD OF GOST 23592-79
GOST 23592-96
INTERSTATE STANDARD
Installation of electrical radio-electronic equipment and devices
GENERAL REQUIREMENTS FOR VOLUMETRIC INSTALLATION OF ELECTRONIC EQUIPMENT AND ELECTRICAL EQUIPMENT
Electrical wiring of radio-electronic equipment and devices. General requirements for three-dimensional wiring of electronic and electrical devices
Introduction date 2001-07-01
1 area of use
This standard applies to electrical installation (hereinafter - installation) performed inside radio-electronic equipment, instruments and devices (hereinafter - equipment) using cable products (wires, cables, bundles, etc.).
The standard establishes general requirements that are mandatory, except for the requirements 4.6.2 , 4.6.6, in the development of technical documentation, manufacture and acceptance of equipment.
This standard does not apply to printed wiring.
2 Normative references
4 Technical requirements
4.1 General technical requirements
4.1.1 Installation of equipment elements should be carried out in accordance with the requirements of this standard for regulatory documentation (hereinafter - RD) for equipment of a particular type and design documentation (CD), approved in the prescribed manner.
4.1.2 Requirements for cutting and fastening the cores of installation wires must comply with GOST 23587.
4.1.3 Requirements for cutting and connecting wire screens must comply with GOST 23585.
4.1.4 Requirements for harnesses must comply with GOST 23586.
4.1.5 Marking of wires and electronic products (IET) must comply with the requirements of GOST 23594.
4.1.6 Markings applied in accordance with the design documentation on the chassis and IEP must be clear and easy to read.
4.1.7 Installation should ensure the operation of the equipment under the influence of external factors according to GOST 15150 and GOST 25467.
4.1.8 Production facilities for assembly and installation must comply with the requirements GOST 12.1.005 and current technological and sanitary standards.
4.1.9 Technical requirements for the installation of equipment should be specified in the design documentation with a reference to this standard.
"Technical requirements for installation - in accordance with GOST 23592-96"
4.1.10 IEP, wires, materials and components used during installation must comply with the requirements of standards and other RD for them and be approved for use.
4.1.11 The design and installation of the equipment should provide access to its elements for the purpose of inspection, verification, replacement and connection of control equipment.
The moving parts of the blocks must not touch the wires. The distances between them are specified in the design documentation.
4.1.12 During installation, the following design measures should be taken to reduce the influence of some circuits on others:
The length of the mounting wires of high-frequency and impulse circuits should be the smallest, for which the elements of high-frequency circuits connected to each other should be located in close proximity, and the connections between such elements should be the shortest;
Individual wires that are most susceptible to interference or that create them themselves must be shielded or twisted;
Unshielded wires of high-frequency circuits, when crossing them, should be located, if possible, at an angle close to 90 °. With a parallel arrangement, such wires should be as far away from each other as possible, separated by a screen or retinue.
The requirements of this paragraph must be specified in the design documentation.
4.1.13 The distance between non-insulated current-carrying surfaces of the equipment must be at least 2.0 mm.
The distance between non-insulated conductive surfaces during installation must be at least 1.0 mm. This distance may be reduced to 0.4 mm if these surfaces are coated with electrically insulating varnishes or compounds.
4.2 Installation requirements for wires, harnesses and cables
4.2.1 Mounting wires in cross-sectional area must correspond to the load current and allowable voltage drop, have the necessary mechanical and electrical strength.
It is preferable to use wires with insulation that is resistant to adhesives, waterproof varnishes and solvents, as well as to the influence of external influencing factors (temperature, humidity, ionizing effects).
4.2.2 It is not allowed to use mounting wires with damaged insulation, cuts in the wire core and other defects that reduce their mechanical and electrical strength.
It is not allowed to deform and damage the insulation of the wires at the time of gripping the tool, the presence of burrs on the conductive cores.
4.2.3 Uninsulated wires used during installation must have an anti-corrosion coating.
4.2.4 The minimum bending radius of the wires must not be less than the value specified in the specifications for them. In the absence of such instructions, the bending radius must be at least twice the outer diameter.
4.2.5 Mounting wires, bundles and cables must be attached to structural elements and must not be located on sharp edges and ribs of the chassis, assemblies and equipment. If this is not possible, it is allowed to lay wires, bundles and cables on the ribs and edges of the chassis, provided that measures are taken to protect the wires, bundles and cables from damage (winding with tapes, use of insulating gaskets, tubes).
4.2.6 The connection of wires with one another, as well as wires with IET leads and IET leads among themselves, must be made using contact details.
4.2.7 Mounting wires, flat cables at the joints before soldering must be mechanically fixed.
4.2.8 The total cross-sectional area of the cores of wires and IET leads connected to the contact parts should not exceed the smallest cross-sectional area of the contact part.
4.2.9 Bundles, cables or individual wires moved during operation must be made of flexible stranded wires of the type MGShV, MS16-13, etc. and must not touch fixed parts of the appliances.
4.2.10 If there are shielded wires in the flexible cable, then all shields must be soldered together and brought to the ground contact, unless otherwise specified in the design documentation.
4.2.11 Installation of conductive conductors of tape wires must be carried out only with a fixed position of the tape wire.
4.2.12 The cutting plane of the cable blank must be perpendicular to the axis of the conductors.
4.2.13 When removing insulation from tape wires with stranded conductors, the twisting of the wires must be preserved.
4.3 Installation requirements for IET
4.3.1 During the installation of equipment, measures must be taken to protect semiconductor devices from the effects of static electricity in accordance with the regulatory document for a particular product.
4.3.2 Harnesses, cables and terminals of IET, if necessary, before installation must be straightened in compliance with the requirements of RD.
4.3.3 When straightening the IET leads, it is necessary to ensure the immobility of the lead section with a length of at least 1.0 mm from the body.
4.3.4 Forming the IET leads in such a way that at the point of exit from the housing (insulator) the lead does not experience mechanical forces higher than the values established by the RD on the IET.
4.3.5 When straightening, forming, installing and fixing the IEP, the coating of the terminals is not allowed to be damaged, with the exception of traces (prints) of the tool, which does not violate their coating (exposing the base material) and does not reduce the mechanical strength.
4.3.6 Forming of the IET leads (if there are no requirements for the distance from the IET case to the center of the lead bend radius to the bend radius) in the state standards and technical specifications for them, must be made with the following dimensions:
a) distance from the IET body to the center of the outlet bending radius, mm, not less than: | |
1) for semiconductor devices .............................................................. ......................................... | |
2) for resistors and capacitors with a diameter (thickness) of the output up to 1 mm inclusive .............................................. ................................................. ................................................ | |
3) for resistors and capacitors with a diameter (thickness) of the output over 1 mm .............. | |
4) for chokes ........................................................ ................................................. ......................... | |
b) bending radius, mm, not less than: | |
1) with a diameter (thickness) of the output up to 0.5 mm inclusive .............................................. ........... | |
2) over 0.5 to 1.0 mm inclusive ....................................... ............................................... | |
3) with a diameter (thickness) of the output over 1.0 to 1.5 mm inclusive .............................. | |
4) with a diameter (thickness) of the outlet over 1.5 m .............................. ................................ | 1.0-1.5 outlet diameter |
4.3.7 With an increase in the density of installation and the location of the IET close to the chassis, electrical insulating tubes must be put on the cases and terminals of the IET, which must be reflected in the design documentation. In this case, the temperature regime allowed for the IET must be maintained.
4.3.8 The inner diameter of the insulating tube should be chosen so as to ensure its tight fit on the IET case. The length of the tube should exceed the length of the IET body by 0.5-1.0 mm on each side.
4.3.9 IEP must be mechanically fastened to the contact part with subsequent soldering, and, if necessary, additionally with the help of clamps, brackets, holders, filling with a compound, installation on glue.
4.3.10 The method of additional fastening of the IEP is selected based on the requirements of the specifications for the IEP, their weight, overall and design characteristics, as well as the operating conditions of the equipment and is indicated in the design documentation.
4.3.11 Mechanical fastening of the IET leads should be carried out by performing at least one turn around the contact piece, busbar or by inserting a flat contact into the hole with tight crimping of the lead. Bending of the contact piece is not allowed.
4.3.12 IET leads, wires must freely enter the mounting holes without force, with rivets, with the obligatory subsequent bending of the lead, wires.
4.3.13 The number of IET leads (including cores of wires) attached to the contact part should be determined depending on the length of the contact, the diameters of the IET leads (wires) and the mechanical strength of the contact part. Their number should not exceed four.
4.3.14 The distance from the end of the cylindrical contact to the fixed terminal of the IET wire must be at least 0.5 mm. The distance from the board to the fixed cylindrical wire terminal must be at least 1.0 mm, and to the flat terminal - at least 0.5 mm.
4.3.15 Each IET output and wire core must be fixed to the contact piece separately. It is not allowed to twist the IET leads, wires with each other and the IET leads with wire cores.
4.3.16 The conclusions of the IET, selected when setting up and adjusting the device, should be soldered without mechanical fastening to their full length. After choosing the IET, its conclusions must be molded and mechanically fixed to the contact part.
4.3.17 Free outputs of relays and transformers are not allowed to be used as contact parts.
4.4 Requirements for mounting connectors
4.4.1 Installation of wires in connectors should not change the force of articulation and dismemberment of the plug with a socket more than is allowed by the regulatory document (ND) for the missing type of connector. The installation of connectors with floating contacts, as well as the filling of connectors with sealants, should be carried out with the mating technological part of the connectors, unless otherwise specified in the RD.
4.4.2 Shanks of contacts of connectors for volumetric mounting should provide a strong connection with wires by one of the following methods: soldering, crimping, wrapping. The specific installation method and the number of resoldering are specified in the ND.
4.4.3 Installation of connectors, the design of which does not provide for fixing the ribbon wire, the soldering zone is filled with compound, should be carried out in a device that fixes the ribbon wire relative to the connector.
4.4.4 Shanks of contacts of connectors for volumetric mounting should allow connection of wires with the section specified in RD.
4.4.5 Connectors supplied for installation must be unpreserved.
4.4.6 In the process of soldering connectors, measures must be taken to prevent the ingress of solder and flux on the contact part of sockets and pins.
4.4.7 After checking the quality of the soldering, the contact shanks must be protected with insulating tubes or covered with a sealant or compound. The tubes must simultaneously protect the places where the cores of wires and cables are exposed, as well as the shanks of the contacts. Damage to the tubes put on the shanks of contacts and clamps is not allowed.
4.5 Requirements for soldering field connections
4.5.1 The materials used during installation must, in their composition and quality, meet all the requirements specified in the relevant state standards.
4.5.2 The materials used must have certificates indicating the date of manufacture, brand and expiration date.
4.5.3 Conductive wires should be tinned over the entire soldering surface. An untinned section of the core is allowed at a distance of up to 1 mm from the end of the insulation.
4.5.4 It is not allowed to deform the conductors at the point of transition from the tinned section to the non-tinned section.
4.5.5 The tinned surface of current-carrying conductors, terminals of elements must be shiny or light matte. The presence of pores and sagging in the form of sharp protrusions is not allowed.
4.5.6 Soldering field connections in the equipment should be carried out after mechanical assembly and checking the circuit elements for compliance with the requirements of the design documentation.
4.5.8 The tail of the connector contact must be tinned if it has not been previously tinned.
4.5.9 Shanks of connector contacts after the expiration of the guaranteed solderability before installation must be subjected to preliminary hot tinning.
4.5.10 Solder and flux for soldering should be selected depending on the materials being soldered, the allowable heating of the mounting elements and operating temperatures and are indicated in the design documentation.
As the main ones, solders of the POS 61 and POS 61M grades according to GOST 21930 should be used.
4.5.11 When fluxing, the flux inside the IET on the contact parts of the connectors is not allowed. When soldering cells and blocks that have non-hermetic IET in their design, they should be placed in a position that prevents the flux from flowing into the IET and getting on the surfaces of the contacting contacts of the relay and connectors.
When using tubular solders and solder pastes, additional fluxing can be omitted.
4.5.12 The rod of the electric soldering iron must be cleaned of carbon deposits, tinned and have a flat surface without burrs.
4.5.13 The shape of the rod of the electric soldering iron and the angle of sharpening should be selected depending on the design of the unit to be soldered.
4.5.14 Checking the temperature of the soldering iron rod should be carried out at least twice per shift: before starting work and after a break with a mark in the document of the form established at the enterprise, as well as when replacing it, sharpening or changing the soldering mode.
4.5.15 The soldering temperature must correspond to the range of flux and solder thermal activity and not exceed the maximum allowable values specified in the RD for elements of specific types.
In the absence of such instructions, the temperature of the soldering tip should be for solder POS 61 and POS 61M from 240 to 280 ° C.
4.5.16 The soldering and tinning time of the IET leads should not exceed the value specified in the RD for elements of specific types. In the absence of such restrictions, the duration of the process should be no more than 5 s.
4.5.17 The distance from the IET body to the place of soldering (tinned surface) of the output must be at least the value specified in the RD for elements of a particular type. In the absence of such instructions, this value shall be at least 1 mm.
4.5.18 When stepwise soldering field joints, each subsequent soldering should be done with solder, the melting temperature of which should be 30-40 ° C lower than the melting temperature of the solder with which the previous soldering was performed, or with the same solder, while desoldering the previously formed seam is not allowed.
4.5.19 Soldered joints should not have cracks, large pores, sharp protrusions, coarse grains, convex fillets, sagging, large needle and dendritic formations, solder bridges. Soldering should be, if possible, skeletal, i.e. under the solder, the outline of the soldered leads and wires should be visible. Incomplete filling with solder of holes with a diameter of more than 3 mm is allowed.
The surface of the solder along the entire perimeter of the solder joint must be continuous, smooth, glossy, without dark spots and foreign inclusions.
A matte or shiny surface of solder with matte spots is allowed in a solder joint with silver, gold, nickel, tin-bismuth, cadmium coatings.
"Greening" is allowed near soldering points and under insulation for copper wires such as MGTF, MP 17-11, etc., which do not have a coating.
4.5.20 The surface of solder joints should be cleaned with a lint-free cloth or a brush moistened with ethyl alcohol or an alcohol-nefras (alcohol-petrol) mixture in a ratio of 1:1. In this case, nefras C3-180/120 (BR-1 gasoline) according to ND, ethyl alcohol according to GOST 18300 should be used.
It is allowed to use other materials and cleaning methods that do not reduce the quality of the joints.
Solder joints should be cleaned after each solder or group of solders.
Washing liquid must not get inside leaking parts of the equipment.
4.6 Requirements for solderless mounting methods
4.6.1 When installing by winding, unmodified, modified and bandage connections are used. The type of connection must be defined in the technical requirements of the drawing.
4.6.3 When performing winding installation, the wires between the contacts of the pins should be laid without tension.
4.6.4 When performing installation by wrapping, it is not allowed:
Make a connection with a wire straightened after the connection is untwisted;
Deform connections (compress, shift coils, etc.);
Overlapping of turns on each other in the connection.
4.6.5 The end of the last turn of the wired connection must fit snugly against the contact pin.
4.6.7 The protrusion of the end of the crimped wire at the exit from the contact shank should be no more than 1.5 mm.
4.6.8 The surface of the contact shank after compression should not have cracks, burrs, sharp edges, coating damage.
5 Safety requirements
5.1 Installation must comply with the requirements GOST 12.1.004 , GOST 12.1.010 , GOST 12.2.007.0 And GOST 12.4.021.
5.2 To prevent electric shock during installation, it is necessary to reliably ground the housings of supply transformers, fans, ventilation systems and power tools.
Wiring must be of good quality. During installation, electric soldering irons and closed-type sockets with an operating voltage of not more than 36 V should be used. The voltage value must be indicated on the sockets.
5.3 To prevent fire during installation, the following measures should be taken:
Premises for the storage and spill of flammable liquids (flammable liquids) must be insulated and equipped with ventilation;
For storage and transportation of flammable liquids or cleaning materials contaminated with flammable liquids, containers made of unbreakable and non-sparking material, with tight-fitting lids, on which the words “Flammable” and the name of the liquid are applied, should be used;
Work areas must be equipped with fire-fighting equipment (asbestos blankets, sand, fire extinguishers, etc.).
5.4 To comply with safety requirements during installation, it is necessary to follow the rules for protection against static electricity.
5.5 To prevent thermal burns during installation, it is necessary to pre-dry the IEP and the tool before immersing in molten solder. The workplace must be equipped with heat-insulating screens and special stands for electric soldering irons.
5.6 To prevent injuries from mechanical factors, it is necessary to use a special container for parts and materials that ensures safety during their transportation. Moving parts of mechanisms must be protected.
5.7 To prevent poisoning during installation when performing work using solders containing lead, varnishes and adhesives, workplaces must be equipped with exhaust units that ensure the removal of harmful vapors to a rate not exceeding the maximum allowable concentration in accordance with the requirements GOST 12.1.005.
5.8 Illumination of workplaces must comply with [ 2 ].
5.9 Safety requirements not established by this standard must comply with the requirements of the system of labor safety standards.
APPENDIX A
Key words: standard, technical requirements, electrical installation, winding installation, crimping installation, radio-electronic equipment, device, cable products, wire, bundle, ribbon cable, IET terminal, connector, contact shank, soldering
Organization of assembly and installation works. The basis of installation and assembly work is the formation of electrical and mechanical connections.
Assembly is a set of technological operations of mechanical connection of parts and electrical / radio elements (ERE) in a product or part thereof, performed in a certain sequence to ensure their specified location and interaction in accordance with design documents. The choice of the sequence of operations of the assembly process depends on the design of the product and the organization of the assembly process.
Installation is called the TP of the electrical connection of the ERE of the product in accordance with the principal electrical or wiring diagram. Mounting is carried out using printed or wired circuit boards, single conductors, bundles and cables.
In accordance with the sequence of technological operations, the assembly (mounting) process is divided into the assembly (mounting) of individual assembly units (boards, blocks, panels, frames, racks) and the general assembly (mounting) of the product. Organizationally, it can be stationary or mobile, with a concentration or differentiation of operations. An assembly is called stationary, in which the object being assembled is stationary, and the necessary assembly elements are supplied to it. A mobile assembly is characterized by the fact that the assembly unit moves along the conveyor along the workplaces, each of which is assigned a certain part of the work. The movement of the assembly object can be free as the pinned operation is performed or forced in accordance with the rhythm of the process.
Assembly according to the principle of concentration of operations is that at one workplace the whole complex of works on the manufacture of a product or its part is performed. This increases the accuracy of the assembly, and simplifies the normalization process. However, the long duration of the assembly cycle, the complexity of the mechanization of complex assembly and assembly operations determine the use of this form in the conditions of single and small-scale production.
A differentiated assembly involves the division of assembly and installation work into a series of successive simple operations. This allows you to mechanize and automate work, use low-skilled workers. Assembly according to the principle of differentiation of operations is effective in serial and mass production. However, excessive fragmentation of operations leads to an increase in transportation time, an increase in production space, and an increase in worker fatigue when performing monotonous actions. In each specific case, the technical and economic feasibility of the degree of differentiation of assembly and installation work must be determined.
The requirements for high productivity, accuracy and reliability are imposed on assembly and assembly processes. The increase in labor productivity is significantly influenced not only by the degree of detail of the process and the specialization of jobs, the level of mechanization and automation, but also by such organizational principles as parallelism, direct flow, continuity, proportionality and rhythm.
Assembly parallelism is the simultaneous assembly of several parts of a product or products as a whole, which shortens the production cycle. From a technological point of view, two types of ensuring the parallelism of processes have the greatest opportunities: 1) manufacturing and assembling several products simultaneously on multi-subject production lines; 2) combination on automated production lines for the manufacture of parts with their assembly.
The directness of the process is the shortest way for the product to pass through all phases and operations from the launch of raw materials and components to the output of the finished product. Any deviations from straightness complicate the assembly process, lengthen the production cycle of radio equipment. The principle of direct flow must be observed in all departments of the enterprise and combined with the principle of continuity.
The continuity of TP assembly provides for the reduction or complete elimination of inter- or intraoperative breaks. Continuity is achieved by a rational choice of technical processes, by combining the operations of manufacturing parts with their assembly, by including control and adjustment operations in the flow.
The principle of proportionality is understood as proportional productivity per unit of time at each workplace, line, section, workshop. This leads to the full use of existing equipment, production space and a uniform output of products. Improves the proportionality of the rational division of the structure into assembly units and the uniformity of its elements.
The principle of rhythm implies the release of equal or increasing quantities of products at regular intervals. Rhythm during assembly is increased through the use of standard and group processes, their unification and preliminary synchronization of operations.
Design of technical processes for assembly and installation REA begins with the study at all production levels of the initial data, which include: a brief description of the functional purpose of the product, specifications and requirements, a set of design documentation, a program and planned release dates, guiding technical, regulatory and reference material. These data are supplemented by the conditions in which it is supposed to manufacture products: a new or existing enterprise, equipment available on it and the possibility of acquiring new equipment, cooperation with other enterprises, provision of materials and components. As a result of the analysis, a plan for technological preparation and launch of the product into production is developed.
The development of TP for assembly and installation includes the following complex of interrelated works:
1. Selection of a possible standard or group TP and (if necessary) its refinement.
2. Drawing up the route of the TP of the general assembly and the establishment of technological requirements for incoming assembly units.
3. Drawing up TP routes for assembling blocks (assembly units) and establishing technological requirements for their assembly units and parts.
4. Determination of the necessary technological equipment, equipment, means of mechanization and automation.
5. Breakdown of TP into elements.
6. Calculation and assignment of technological regimes, technical regulation of work and determination of the qualifications of workers.
7. Development of technological process and choice of means of control, adjustment and regulation.
8. Issuance of technical specifications for the design and manufacture of special technological equipment.
9. Calculation and design of a production line, a serial assembly site or a flexible production system, drawing up layouts and developing operations for moving products and production waste.
10. Selection and appointment of in-shop lifting and transport vehicles, organization of a picking site.
11. Registration of technological documentation for the process and its approval.
12. Release of an experimental batch.
13. Correction of documentation based on the test results of an experimental batch.
The development of a technological route for the assembly and installation of REA begins with the dismemberment of the product into assembly elements by constructing assembly diagrams. The elements of assembly and assembly production are parts and assembly units of varying degrees of complexity. The construction of schemes allows you to establish the sequence of assembly, the relationship between the elements and visualize the TP project. First, a diagram of the assembly composition of the entire product is drawn up, and then it is supplemented with detailed diagrams of individual assembly units. The division of the product into elements is carried out regardless of the program of its release and the nature of the assembly process. The scheme of the assembly composition serves as the basis for the development of the technological assembly scheme, in which the structure of the assembly operations is formed, their optimal sequence is established, and instructions are made on the features of the operations.
In practice, two types of assembly schemes are used: "fan" and with a base part (Fig. 3). Assembly elements on assembly diagrams are represented by rectangles in which their name, classifier number, reference designation and quantity are indicated. More time-consuming, but visual and reflecting the temporal sequence of the assembly process, is a diagram with a base part. The chassis, panel, board or other part from which the assembly begins is taken as the base.
The composition of the assembly operations is determined based on the optimal differentiation of assembly production. In non-flow production, the appropriate technological boundaries of differentiation are:
Homogeneity of work performed;
Obtaining as a result of the operation a complete system of surfaces of parts or a finished assembly element;
independence of assembly, storage and transportation from other assembly units;
the possibility of using simple (universal) or reconfigurable technological equipment;
Ensuring the minimum proportion of auxiliary time in the operation;
standard and group operations established in this production.
In mass production, the necessary level of differentiation of operations is mainly determined by the rhythm of assembly.
The optimal sequence of technological operations depends on their content, the equipment used and economic efficiency. First of all, fixed connections are made that require significant mechanical effort. At the final stages, moving parts of products, detachable connections are assembled, parts that are replaced during the setup process are installed.
The developed assembly scheme allows you to analyze the technological process taking into account technical and economic indicators and choose the optimal one from both a technical and organizational point of view.
Typical and group assembly and installation processes. The need to develop new products in a short time, together with high requirements for quality and technical and economic performance of enterprises, require constant improvement of the technological preparation of assembly and assembly production. The main direction of such improvement is the unification of TP in conjunction with the unification of the assembled structural elements. There are two types of TP unification: typing and group methods of assembly and installation.
A typical TP is a schematic assembly and installation process of products of one classification group, including the main elements of a specific process: the method of installing the base part and orienting the rest, the sequence of operations, types of technological equipment, operating modes, approximate labor intensity for a given output of products. According to the standard process, a specific assembly process of the product is easily compiled and, with its appropriate preparation, these functions are transferred to the computer.
A prerequisite for typing is the classification of parts, assembly units and blocks according to the signs of constructive (dimensions, total number of connection points, basing scheme, etc.) and technological (assembly route, content of transitions, equipment) commonality. When typing, four classification steps are adopted: class, species, subspecies, type.
A class is a classification group of assembly units that have a general view of an assembly connection, for example: screwing, soldering, welding, gluing, etc.
View is a set of assembly units, characterized by the degree of mechanization of the assembly process: manual assembly, using a mechanized tool, automated. Views are divided into subspecies that differ from each other in structural elements, for example, adhesive overlap, with overlays, butt, corner, etc. Types combine assembly units that have the same assembly conditions, location and number of attachment points.
 Rice. 4. |
In terms of complexity, TP typification methods are divided into three groups: simple (one operation), conditionally simple (one TP) and complex. The first group includes methods of direct typing without preliminary unification of the collected elements, based on the commonality of technological equipment. The second group combines typification methods related to the ways of connecting ERE and parts, using common technological solutions for various classes, assembled elements, building various technological routes from a set of normalized operations. The third group includes methods that use the normalization of elements of the production process with additional normalization of ERE and parts (Fig. 4).
Installation of REA
When installing REA, you must comply with electrical safety requirements and work only with serviceable power tools. Soldering iron and local lighting lamps must have U ≤ 42V. To lower the voltage, transformers are used, one end of the secondary (lowering winding and metal casing must be grounded).
When installing radio circuits, it is prohibited:
- check by touch the presence of voltage and heating of the current-carrying parts of the circuit;
- use wires with damaged insulation to connect blocks and devices;
– carry out soldering and installation of parts in live equipment;
- measure voltages and currents with devices with bare wires and probes;
– replace the fuses in the switched on equipment;
– work on high-voltage installations without protective equipment.
Modeling, examination of REL, performance checks are carried out by at least 2 people: engineering and technical personnel with a qualification group for TB not lower than IV and a worker with a TB group not lower than III. The place of work must be fenced and equipped with protective equipment. In this case, the equipment is connected to a separate electrical panel or to a separate group of fuses. The wires used for the external connection of devices must be enclosed in metal grounded (zeroed) sheaths. At voltages up to 500 V, the use of hose wires and cables is allowed.
It should be remembered that if, in order to eliminate interference and interference, it is required not to ground the case, then adjustment should be carried out using protective equipment.
Equipment setup
Adjustment of large-sized electronic equipment (single-case, multi-case equipment, which is installed on the floor with block sizes > 700 x 700 mm) is carried out by at least 2 people, one with a safety group of at least IV, the second - III.
Adjustment of small-sized equipment can be carried out by one person who has a safety group not lower than III to 1000V and not lower than IV over 1000 V in the presence of a second person nearby who has a safety group not lower than III.
Adjustment work is allowed in specially designated areas and in production facilities where equipment is being developed or operated. These places are fenced off and outsiders should not be in the zone.
To adjust small-sized equipment and individual blocks of large-sized ones, workplaces with control and measuring equipment are organized. At each workplace, it is allowed to simultaneously establish one unit of REA. The work table must be made of dielectric material, have shelves for instrumentation and power supplies and be equipped with a separate panel with a general switch, fuses (automatic devices), signal lamp (voltmeter), recessed sockets and a ground bus with screw terminals.
Adjustment of plug-in blocks of large-sized equipment is allowed to be carried out at the place of its location, if it is impossible to adjust the blocks separately. In this case, it is allowed to use any strong support made of dielectric material.
In this case, a portable electrical panel can be used for power supply, the requirements for which are the same as for a stationary one.
When adjusting the block under voltage, all work on other parts of the equipment being adjusted must be stopped, live parts are fenced. Simultaneous adjustment of several units under voltage is prohibited.
Eliminate defects in the electrical circuit, replace parts is allowed only after the voltage is removed from the equipment and there are no residual charges using a grounded spark gap.
When measuring parameters with the housing removed and the locks shorted, the following TB rule must be observed:
- all prepared work must be carried out with the voltage removed;
– before applying voltage, the metal cases of the measuring equipment must be grounded. If grounding introduces distortion (pickup), then work is allowed without grounding, but with the use of temporary fences, warning posters and protective equipment;
- location and connection of instrumentation and electric circuit with U > 1000V. It is necessary to protect, hang out posters, leave access only to the controls.
