General specification of mechanical and physical design and manufacturing for military electronic equipments
Some standard content:
Military Standard of the Electronic Industry of the People's Republic of China SJ20053-92
Military Electronic Equipment
General Specification of Mechanical and Physical Design and Manufacturing for Military Electronic Equipments Issued on February 1, 1992
Approved by the Ministry of Electronics Industry of the People's Republic of China and implemented on May 1, 1992
Referenced Documents
General Requirements
Equipment Structure
Mobility and Lightweight
Standardization
Reliability and Maintainability
Electromagnetic Compatibility
Safety…
Processability
Man-Machine-Environment System Engineering
Environmental Adaptability
Interchangeability·
5 Detailed Requirements
Structural Design Procedure||tt| |Thermal design
Shock absorption design
Seal design
Indication and control
Working environment
Parts design and manufacturing
Material selection
Casing, chassis, cabinet
Printed circuit board..
Surface mounting technology
Mechanical and electrical installation
Welding process
Cleaning treatment
Surface coating
Paint coating
People's Republic of China Electronic Industry Military Standard Military Electronic Equipment
General specification of mechanical and physical design and manufacturing for military electronic equipments1 Scope
1.1 Subject content
This standard specifies the general requirements for the structural design and manufacturing of military electronic equipment (hereinafter referred to as equipment). This standard also specifies the requirements for parts, equipment, manufacturing processes and application programs of the equipment. 1.2 Scope of application
This standard applies to military electronic equipment and corresponding supporting equipment and spare parts. Special requirements for specific equipment should be specified in the standards of the specific equipment. 2 Referenced documents
GB1184
GB1804
GB2705
GB2900
GB3181
GB3784
GB4054
GB4099
GB 6403.1~5
GB6414
GB8898
GB9315
GJB100
GJB150
GJB151
GJB152
Form and position tolerancesTolerances and fits for dimensions without tolerancesLimit deviations for dimensions without tolerancesClassification, naming and model of coating products
Electrical terms
Basic size series of plug-ins with a height of 44.45 mmStandard sample of paint film color
Radar terms
Paint coating marks
Common terms, terms and their codes (symbols) for navigationComponent structural elements||tt| |Tolerance of casting dimensions
SJ20053-92
Safety requirements for household and similar general purpose electronic and related equipment powered by mains supplyOutline dimension series for printed circuit boards
General technical requirements for military ground radarsCommon terms and termsBasic dimension series for panels, racks and framesEnvironmental test methods for military equipment
Requirements for electromagnetic emission and sensitivity of military equipment and subsystemsMeasurement of electromagnetic emission and sensitivity of military equipment and subsystemsPromulgated by the Ministry of Electronics Industry of the People's Republic of China on February 1, 1992 and implemented on May 1, 1992
GJB267
GJB362
GJB368
GJB403||tt| |GJB450
GJB471
GJB643
SI1276~1285
SJ1372
SJ2167
SJ2267
SJ10166
SJ10167
SI20133
3Definition
SJ20053—92
General specification for design of airborne radar
General specification for printed circuit boards
General technical conditions for military communication equipment Design and manufacturing requirements General specification for equipment maintainability
General technical conditions for shipborne radar
General outline for reliability of equipment development and production Marking of military equipment
Maintainability specification for general radar and director
Classification, characteristics, application scope and marking of metal coating and chemical treatment layer Quality inspection of metal coating and chemical treatment layer Dimensional tolerance of plastic parts
General technical conditions for electronic equipment cabinet
General technical conditions for mechanical and electrical installation of military electronic equipment Technical conditions for sealing structure of electronic equipment
Test method for sealing structure of electronic equipment
Design procedure for structure of military electronic equipment
The terms and definitions of this standard shall comply with the provisions of GB2900, GB3784, GB4099, GB6403.1~5, GIB74.2, GJB267, GJB367.1 and GJB403.
4 General requirements
4.1 Equipment structure
4.1.1 The design of equipment structure shall comply with the requirements specified in this standard. 4.1.2 Equipment (especially portable and mobile equipment) should be designed for usability, with the purpose of simple and flexible operation and easy use, to ensure that work can be carried out quickly under specified environmental conditions. It should be safe and reliable, and easy to install, use, maintain and transport. 4.1.3 The equipment structure should have sufficient mechanical strength and rigidity. The equipment structure should have good processability. New technological achievements should be actively adopted and new materials should be selected. 4.1.4
4.1.5 The structural dimensions of the equipment should comply with the size series specified in the relevant standards. 4.1.6 The equipment has a novel and beautiful shape and excellent craftsmanship. It meets the requirements of engineering psychology. 4.1.7 Under the premise of ensuring the performance and quality reliability of the equipment, the functional life, manufacturing cost, maintenance and use costs of the equipment should be comprehensively demonstrated, the complexity of the equipment should be reduced, and a reasonable structural form should be adopted to adapt to the corresponding production combination type. Use economic precision, reduce costs and improve economic benefits. 4.2 Mobility and lightweight
4.2.1 The equipment should be designed with high mobility and lightweight. Improve the volume filling factor to achieve small size and light weight. Use light materials to the maximum extent possible to reduce the overall weight. 4.2.2 Equipment should be modular. Use easily disassembled structures for easy transportation and installation. 4.2.3 Equipment used in the field should be easy to conceal and camouflage. Generally, military green paint is used. It is allowed to be replaced with other protective color paints in combination with the actual situation of the marching status and position layout (proposed by the ordering party and implemented by the contractor). 4.2.4 Equipment used in the field should not have mixed light. Its lighting and indicator lights (including car lights) should be able to prevent air defense and fog. 2
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4.2.5 If there is a requirement for anti-infrared reconnaissance, measures should be taken during the design. The protection indicators shall be negotiated by the ordering party and the contractor. 4.3 Standardization
4.3.1 In the design and manufacture of equipment, national standards, national military standards and industry standards shall be implemented. 4.3.2 Equipment design shall use standard parts, general parts and borrowed parts to the maximum extent possible. 4.3.3 Equipment design should take into account universalization, serialization, combination and modularization. 4.3.4 During the design stage of a new product, the chief designer or chief technical officer shall, together with the standardization department, organize the preparation of the "Outline for Standardization of New Products" and clearly put forward the standardization requirements for this product. 4.4 Reliability and maintainability
4.4.1 The reliability design of the equipment shall comply with the provisions of GJB450. 4.4.2 The maintainability design of the equipment shall comply with the provisions of GJB368 or GJB643. 4.5 Electromagnetic compatibility
The electromagnetic compatibility of the equipment shall comply with the provisions of GJB151, and its inspection method shall comply with the provisions of GJB152. 4.6 Safety
The safety of the equipment shall comply with the provisions of GB8898.
4.6.1 Conduct safety design through safety analysis. Select reasonable structural forms, components and materials, and design reasonable operating procedures to ensure personal safety and equipment safety. 4.6.2 The dangerous parts of the equipment should be equipped with electrical and mechanical interlocking devices, and alarms should be given in the form of sound and light. At the same time, it should be clearly stated in the instructions for use.
4.7 Processability
4.7.1 On the premise of meeting the performance requirements of the equipment, the design of the parts, components and complete parts of the equipment should have good structural processability, the manufacturing process should be economical and reasonable, and typical processes should be used first. 4.7.2 New processes, new technologies and new materials that have been proven to guarantee product quality requirements through tests should be used. 4.7.3 The use of raw materials and processes that may pollute the environment or endanger human life should be limited. 4.8 Man-machine-environment system engineering
4.8.1 The design of equipment should apply the basic principles and principles of man-machine-environment system engineering to ensure human-machine safety, improve work efficiency and give full play to the effectiveness of the system.
4.8.2 In the design of equipment, the following factors should be considered: a.
The intelligence, physical strength and psychological state of the operator; the requirements for operating and maintenance space;
the perceptual requirements of vision and hearing;
the location arrangement of controllers, displays and instruments; the minimum range of inherent errors of operators when the equipment works under adverse environmental conditions; comfort factors related to work efficiency;
the influence of climatic and mechanical environmental conditions on the ability of operators; the consistency of the operating procedures of new equipment with the accustomed operating procedures. h.
4.9 Environmental adaptability
The environmental adaptability of the equipment shall be clearly specified in the product standards (technical conditions) according to the provisions of GJB150 and other relevant standards and the requirements of the ordering party.
4.10 Interchangeability
4.10.1 The equipment shall have good interchangeability, and the parts, components and complete parts that need to be interchangeable shall be interchangeable without special processing and adjustment3
.
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4.10.2 Equipment of the same model produced in different factories and batches shall be produced according to the same drawings to ensure that the wearing parts and key components, parts, components and whole parts of the equipment can be interchanged. 4.10.3 When selecting components and parts, while meeting the performance and interchangeability requirements, general components and parts with a larger tolerance range shall be selected.
5 Detailed requirements
5.1 Structural design procedure
The equipment structural design procedure shall comply with the provisions of SJ20133. 5.2 Thermal design
5.2.1 The basis for system thermal design is: environmental conditions and working conditions of the equipment, power consumption of components, equipment configuration, reliability indicators, maintainability indicators, etc. Thermal design shall ensure that the equipment operates normally within the extreme operating temperature range specified by tactical and technical requirements and technical conditions.
5.2.2 The derating of components and materials should be organically linked to the cooling of carriages, cabinets, extensions and other equipment, and the best system heat dissipation effect should be achieved.
5.2.3 Natural cooling should be considered first. Only when the heat density is too large and the natural cooling method cannot meet the heat dissipation requirements, forced air cooling, water cooling, air conditioning or other special cooling methods should be used. 5.2.4 All exhaust vents, air inlets, air paths, air ports, shutters, etc. for ventilation and heat dissipation should be equipped with dust filter treatment devices. 5.2.5 The selected fans, pumps, etc. should have reliability indicators. And the noise, vibration frequency and amplitude are required to be lower than the specified values. 5.2.6 For systems using liquid cooling or evaporative cooling, the physical and chemical stability of the working medium should be considered and meet the specified values. 5.2.7 The cooling and heating systems should not pollute the working environment or damage the components, and should be easy to clean and repair. 5.2.8 The cooling and air conditioning systems should consider the interlocking control protection with the high-voltage power supply lines of key components (combinations). In case of a fault, it can automatically cut off the high voltage, send out a warning signal, and automatically reset after normal operation. 5.2.9 Complex and important cooling systems should have necessary parameter control devices and fault displays. 5.2.10 The components, materials, and protective coatings of the cooling system should have the functions of corrosion resistance, mildew resistance, and moisture resistance. The structure of the system should not damage the shielding and grounding performance of the equipment, and the high voltage should consider the withstand voltage insulation. 5.2.11 The heat consumption of the equipment should be considered for heat recovery in winter to save energy. 5.3 Shockproof and buffering design
5.3.1 The shockproof design should be carried out correctly according to the use environment of the equipment, the shock absorbing device should be selected correctly, and the arrangement should be reasonable. Ensure that the equipment can work normally under the specified conditions. 5.3.2 Airborne, shipborne, vehicle-borne and other electronic equipment should usually have a complete shockproof and buffering system. After the shock absorbing device is installed, there should be a reliable protective ground wire.
5.3.3 The shock absorbing device should be firm and reliable, easy to disassemble and assemble, and a limiter should be provided if necessary to protect the electronic equipment when the reducer is damaged.
5.3.4 When the height of electronic equipment installed on a carrier is much greater than the length and width, or the center of gravity is too high, in addition to the base, the sides or (and) the back should have shock-absorbing devices.
5.4 Sealing design
5.4.1 The equipment housing should be designed with a sealing structure (water, dust, and air sealing) due to functional requirements. The design requirements for the sealing structure should comply with the provisions of SJ10166.
5.4.2 For cast aluminum alloy housings, pinholes within the allowable range should be sealed by coating and resin dipping processes 4
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5.4.3 For sheet metal housings, sealing requirements must be put forward for welds and rivets, and sealing treatment must be carried out. 5.4.4 The sealing structure test of the housing shall comply with the provisions of SJ10167. 5.5 Indication and control
5.5.1 The control elements of the equipment should be installed on the control panel (or on the joystick), and the number of control elements should be minimized. 5.5.2 The direction and position of the control elements should comply with the following provisions: The movement direction of the control knob and the instrument pointer should be consistent, and if they are inconsistent, they should be explained; a.
The position and direction of switching on, starting, increasing, etc. should make the control element move upward, to the right, and rotate in the clockwise direction; b.www.bzxz.net
The position and direction of switching off, shutting down, reducing, etc. should make the control element move downward, to the left, and rotate in the counterclockwise direction. c
5.5.3 The adjustment of the control element should be convenient, stable and rapid. The display device should not be blocked during operation, and the adjustment of adjacent control elements should not be affected.
5.5.4 The function, role or working position of the indicator and control device should be marked near it. 5.5.5 The adjustment mechanism with automatic positioning device should be able to be correctly positioned and should not be displaced when affected by the external environment. 5.5.6 The adjustable parts in the machine should be in the middle position under normal working conditions. The adjustment range should be able to compensate for the deviation caused by the change of component parameters or the replacement of components during the life of the equipment. The dial should meet the following requirements:
Numbers.
The color of the graduation numbers and the background color of the dial should have a large contrast; the scale and numbers on the dial should be clear and easy to read in the observation position; at least two numbers should be seen for the continuously adjustable window dial; only one number should be seen for the discontinuously adjustable window dial. The locking device should meet the following requirements:
It should be able to ensure that the control element can be adjusted and locked at will within the control range; b.
The operation of locking or unlocking should be convenient;
In the unlocked position, the locking device should not affect the normal operation of the control device; the locking device should be able to work on both the uncontrolled element and the adjustable control element; d.
The locking device has a locking function. When locked, the motor cannot be powered. e.
5.5.9 The display and controller should be reasonably selected and configured. The control and display combination should generally be the display on the top and the control on the bottom or the display on the left and the control on the right.
The response of the display to the control should be clearly visible. 5.5.10 The display should be arranged in the best viewing area of the operator (see Figure 1). The display surface should be perpendicular to the normal line of sight of the operator, and the angle with the normal line of sight should not be less than 45°. 5.5.11 The viewing distance should be controlled within the range of 300~700mm, with 500mm being the best. 5.5.12 The lighting should meet the needs of work and maintenance. 5.5.13 When the required dimming degree of display lighting is not the maximum, an adjustable low-brightness incandescent lamp can be used. If the maximum dimming degree is required, a low-brightness red lamp or a foot lamp should be installed. When multiple displays are combined together, the displays should have a uniform background brightness, so that all brightness is equal in the range from full "on" to full "off".
Maximum 40°
Best 15
Normal line
Best 15°
Maximum 20°
Maximum 65°
Normal sight
Maximum 35
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Best 15°
Best 15°
Maximum 35°
Best 0
Maximum 609
Horizontal sight
Normal line
Minimum 459
Maximum 60°
5.5.14 The size and position layout of various control components should take into account the impact of harsh environmental conditions (such as workers wearing cold-proof gloves or operating under no lighting conditions). The size of the control force should also take into account the limitations of the use conditions. 5.6 Operating environment
5.6.1 Workspace device
5.6.1.1 Sufficient space should be left in front of the workspace console so that the maintenance equipment can be pulled out. 5.6.1.2 Leg and knee space The leg and knee space under the workbench should be considered as follows: height 480~580mm; width 420~500mm; depth 380~450mm.
5.6.1.3 The seat can be raised and lowered 380~480mm, the angle between the seat cushion and the backrest should be 100°~115°, and the shape of the backrest should fit the back shape of the human body.
5.6.2 Temperature
5.6.2.1 Heating The cabins and rooms where operators work for a long time should be equipped with heating equipment to keep the cabin and room temperature above 10℃, and the temperature in fixed working rooms should not be lower than 18℃; 5.6.2.2 Ventilation In the operating room, an air volume of 0.238~0.850m3 per person per minute should be provided (about two-thirds should be fresh air). The wind speed passing by people generally does not exceed 20m/min, and the maximum is 30m/min; 5.6.2.3 Air conditioning should keep the working environment within the temperature range suitable for people or below 29℃. The design of air conditioning equipment should ensure that the cold air flow does not blow directly to the human body; 5.6.2.4 Temperature uniformity In cabins and rooms with air conditioning and heating equipment, the temperature difference between the floor plane and the head should be less than 6
5.5℃.
5.6.3 Humidity
SJ20053-—92
When the temperature is 20, the relative humidity should be between 45% and 65%; when the temperature rises, the relative humidity should be reduced, but not less than 15% to prevent the materials and operators from being unsuitable. 5.6.4 Noise Limit
The noise level in the power station cabin and room should be lower than 85dB (A). If it exceeds the limit, the workers should be protected. During the design, noise reduction measures should be taken as much as possible. The noise in the working unit should be lower than 75dB (A). The noise level in the launch cabin and room (launch and receiving cabin and room) should generally be lower than 75dB (A), with a limit of 85dB (A). All measurement points should be selected at the normal working position of the operator, at a height of 1 to 1.5m from the floor. 5.7 Design and manufacturing of parts
5.7.1 Structural elements and dimensional tolerances in drawings 5.7.1.1 Structural elements of parts shall be in accordance with GB6403.1~5 and relevant standards; 5.7.1.2 Limit deviations of dimensions without tolerances shall be in accordance with GB1804; 5.7.1.3 Uninscribed shape and position tolerances shall be in accordance with GB1184; 5.7.1.4 External and internal sharp angles of parts shall be chamfered or rounded with a radius of 0.1~0.5mm; 5.7.1.5 The surface of parts shall not have defects such as sharp angles, burrs, cracks, corrosion, etc. 5.7.2 Fasteners
5.7.2.1 The selection of fasteners shall be reasonable and shall comply with the requirements of relevant national standards or industry standards, and their varieties and quantities shall be reduced. When there are special requirements, special screws are allowed to be used, but special tools must be provided. 5.7.2.2 Fasteners shall be made of corrosion-resistant metal or treated with corrosion-resistant treatment. 5.7.2.3 For fasteners in key positions, torque wrenches should be used and tightened according to the specified torque. 5.7.3 Castings
The design, manufacture and acceptance of various castings of equipment shall comply with the relevant national standards and industry standards. The dimensional tolerances of castings shall comply with GB6414.
5.7.4 Forgings
The design, manufacture and acceptance of various forgings of equipment shall comply with the relevant industry standards. 5.7.5 Weldings
The design and manufacture of welded parts shall comply with the relevant provisions of SJ2267, and the limit deviation of dimensions without tolerance shall comply with GB1804. 5.7.6 Plastic parts
The dimensional tolerances of various plastic parts of equipment shall comply with SJ1372. 5.8 Material selection
5.8.1 Basic requirements for material selection
5.8.1.1 All materials should meet the use requirements: 5.8.1.2 Materials should be based on domestic sources;
5.8.1.3 The selected materials should meet the standards. 5.8.2 Flame retardancy
Flammable or combustion-supporting materials should not be selected (except for those used in sealed refractory containers). Additives should not have a harmful effect on the basic properties of the base material. Non-permanent additives should not be used to improve the flame retardancy of the base material. 5.8.3 Mildew resistance
Inherently resistant materials should be used. If mildew-prone materials must be used, mildew-proof treatment should be carried out in advance (excluding materials inside sealed containers)
5.8.4 Arc resistance
SJ20053—92
Insulating materials with good arc resistance should be used in circuits that are prone to arcing. 5.8.5 Low toxicity and corrosion resistance
Non-metallic materials used for equipment should be materials with good corrosion resistance and chemical stability. After contact with air, acidic or alkaline gases should not be generated, and explosive gases and harmful gases should not be released. 5.8.6 Corrosion resistance of metal materials
Corrosion-resistant or corrosion-resistant metal materials should be selected to avoid close contact between two different metals with large chemical potential differences, otherwise protective measures should be taken. The protective measures can refer to the provisions of relevant national standards or industry standards. 5.8.7 Vibration and impact resistance
Components that are directly subjected to vibration and impact should fully consider the mechanical strength and fatigue strength of the material. 5.8.8 Insulating materials
Basic considerations for selecting insulating materials:
Insulating strength;
Dielectric constant;
Loss factor;
Mechanical strength;
Heat resistance;
Water absorption and moisture permeability;
Fungus resistance;
Ozone resistance.
Hygroscopic insulating materials shall not be used in high-frequency circuits. Hydrophilic materials shall be treated with water. Cotton and linen fabrics shall not be used as fillers for insulating materials. 5.8.9 Organic fiber materials
When using organic fiber materials, the effects of mold protection and shrinkage shall be considered. After the finished product is submerged in water for 24 hours and dried, it shall meet the specified requirements. When used for heavy loads, it shall meet the specified mesh requirements. Delicate fabrics used for carrying and protecting equipment, accessories, and shells shall be protective colors.
5.8.10 Ceramics and Glass
Glass used to protect measuring instruments, meters, indicators, dial windows, and cathode ray tube surfaces should be transparent, flat, and free of bubbles. Anti-glare glass should be used as required.
All surfaces of ceramic parts under electrical stress should be glazed or treated with other surface treatments. 5.8.11 Luminescent Compounds
The brightness, life span, and harm to the human body of the selected luminescent compounds should meet the requirements of the equipment technical conditions and the provisions of relevant standards.
5.8.12 Impregnation and Filling Materials
Impregnation and filling materials should not age and fail within the specified service life, and should not have harmful effects such as corrosion on adjacent parts and materials. There should be no cracks or overflow within the specified ambient temperature range. 5.8.13 Adhesives
All adhesives should be waterproof. Under the specified environmental conditions, the adhesion is strong and has sufficient durability. 5.8.14 Lubricant
Low volatility lubricant should be selected, and should not corrode the contacting materials. Silicon compound and graphite-based 8
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material lubricant should not be used. The lubricant used should ensure lubrication under the specified working environment temperature. 5.8.15 Restricted materials (except packaging materials) Felt, wool, jute, leather, linen, paper, wood, cork, plastic (with cotton and linen as fillers), organic fiberboard, asbestos electrical insulation fiberboard, cellulose acetate, cellulose nitrate, regenerated cellulose, zinc alloy, magnesium alloy, etc. 5.8.16 It is prohibited to use mercury and radioactive materials (except parts, components and complete parts made of mercury and radioactive materials). 5.9 Casing, box, cabinet
5.9.1 The following factors should be considered in the design of casing, box, cabinet: a.
Strength;
rigidity;
corrosion resistance;
waterproof, dustproof, and harmful gas proof;
personnel safety (grounding, corners and edges, etc.); electromagnetic shielding;
heat dissipation;
external connection;
installation characteristics;
j. decoration and shape;
k. weight;
1. Others.
and should be in accordance with the national military standard.
5.9.2 Dimension series of chassis, cabinets and plug-ins 5.9.2.1 The main structural dimensions of equipment cabinets shall be in accordance with GJB100. 5.9.2.2 The basic dimensions of equipment chassis and plug-ins shall be in accordance with GB3047.4. 5.9.2.3 The technical requirements of equipment cabinets shall comply with SJ2167. 5.10 Printed circuit boards
5.10.1 The design and selection of printed circuit boards (including printed circuit board substrates, metal coatings, coatings, conductor width and spacing, aperture pad diameter, etc.) shall comply with GJB362 and GB9315 or industry standards. 5.10.2 Component Arrangement
5.10.2.1 All components shall be arranged neatly, beautifully, tightly painted, with short leads, minimal crossover, no mutual influence, and convenient for repair. Components on printed circuit boards shall be arranged on one side, and a spacing of 1 to 2 mm shall generally be left between components and printed circuit boards. The installation hole spacing of components of the same specification shall be uniform. 5.10.2.2 In order to prevent the printed circuit board from being deformed by force, the components shall be arranged symmetrically. Heavier components shall be installed in fixed positions close to the printed circuit board to lower the center of gravity, and fixing measures shall be taken to tighten them. 5.10.2.3 Components that need to be adjusted must be installed in places that are easy to adjust. 5.10.2.4 Heat-generating components should be placed in a position conducive to heat dissipation or placed separately. 5.10.2.5 Heat-sensitive components should be kept away from high-temperature areas or adopt heat-shielding structures. 5.10.3 The adhesion of printed conductors should be strong. Under the premise of not affecting electrical performance, large-area copper foil should not be used. If large-area copper foil must be used, it should be cut into a fence shape to avoid long-term heating and copper foil peeling after welding. 5.10.4 Printed circuit boards should generally be connected to the system using connectors. When the printed circuit board is directly connected to the system without a connector, measures should be taken to ensure good contact and life indicators. 9
5.11 Surface mounting technology
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5.11.1 Surface mounting technology can be used in electrical structure design. 5.11.2 Surface mounting technology requirements shall be in accordance with the relevant industry military standards. 5.12 Mechanical and electrical installation
Mechanical and electrical installation shall comply with the provisions of SJ2267.
5.13 Welding process
5.13.1 The soldering joints shall be welded in one time to avoid repeated welding and long tinning time. The soldering joints shall be smooth and uniform, with clear outlines, no pores, no burrs, no cracks, and no cold solder joints. 5.13.2 It is not allowed to use acidic or easily corrosive flux. There shall be no residual flux on the welding surface. 5.13.3 The materials and welding quality of structural parts shall meet the requirements of relevant national standards or industry standards. The weld shall be continuous, no cracks are allowed, and it shall be evenly hooked, smooth, without leakage, no harmful pores, no slag inclusions, no material burn-through, etc. Coarse weld nodules, slag inclusions and metal splashes shall be removed. If there are defects such as pores, repair welding is allowed. Harmful stress caused by welding shall be eliminated. 5.13.4 The weld length of intermittent welding is allowed to increase by 25%. 5.13.5 After cleaning, the weld surface is allowed to have pores with a depth and diameter not greater than 1mm and a mutual distance of not less than 5mm. 5.13.6 Parts or components under low stress can be welded by contact welding or intermittent welding, but the number of contact welding points should provide reliable strength for the stress that may be borne.
5.14 Cleaning
5.14.1 Cleaning process and cleaning solvent should not have a harmful effect on the performance of the equipment. 5.14.2 After the components, unit circuits and extensions of the equipment are assembled, they should be cleaned and should not contain dirt, oil stains, fingerprints, dust, flux and other harmful substances and rust. Transmission parts should be relubricated after cleaning. No welding slag, metal chips and other debris should be accumulated inside the equipment.
5.15 Surface coating
5.15.1 The surface coating of parts shall comply with the provisions of SJ42. 5.15.2 The quality of the surface coating of parts shall comply with the provisions of SJ1276~1285. 5.16 Coating
5.16.1 In order to prevent dust accumulation and contamination by radioactive materials, wrinkle paint shall not be used unless required by the ordering party. 5.16.2 The color of the equipment shall comply with the provisions of Article 5.17. And comply with the provisions of GB3181. 5.16.3 The paint model used shall comply with the provisions of GB2705 or the enterprise standard of the paint factory. 5.16.4 The marking of the coating shall comply with the provisions of GB4054. 5.16.5 The coating shall not have defects such as exposed bottom, pinholes, blistering, not dry, biting bottom, sagging, coarse particles, whitening, powdering, cracking, damage, etc.
5.16.6 The interior of the debugged equipment shall be sprayed with moisture-proof, mildew-proof and salt spray-proof paint. For the parts that cannot be sprayed, effective protection shall be carried out.
5.17 Color
5.17.1 Protective color
The exterior color of various equipment (unless otherwise required by the ordering party) shall be as follows: a. Sea gray or light gray (semi-gloss): used for indoor electronic equipment and console panels, cabinets and casings of electronic equipment in ships, tanks, cabins (rooms);
b Black (matte): used for various parts of equipment in aircraft cabins and the outer surface of transformer sealed shells; C. Military green (matte): used for various parts of ground open-air equipment and exposed parts of portable electronic equipment; 105 The coating is not allowed to have defects such as exposed bottom, pinholes, blistering, not drying, biting bottom, sagging, coarse particles, whitening, powdering, cracking, damage, etc.
5.16.6 The interior of the debugged equipment should be sprayed with moisture-proof, mildew-proof and salt spray-proof paint. For the parts that cannot be sprayed, effective protection should be provided.
5.17 Color
5.17.1 Protective color
The exterior color of various equipment (unless otherwise required by the ordering party) shall be as follows: a: Sea gray or light gray (semi-gloss): used for indoor electronic equipment and console panels, cabinets and casings of electronic equipment in ships, tanks, cabins (rooms);
b Black (matte): used for various parts of equipment in aircraft cabins and on the outer surface of transformer sealed shells; C. Military green (matte): used for various parts of ground open-air equipment and exposed parts of portable electronic equipment; 105 The coating is not allowed to have defects such as exposed bottom, pinholes, blistering, not drying, biting bottom, sagging, coarse particles, whitening, powdering, cracking, damage, etc.
5.16.6 The interior of the debugged equipment should be sprayed with moisture-proof, mildew-proof and salt spray-proof paint. For the parts that cannot be sprayed, effective protection should be provided.
5.17 Color
5.17.1 Protective color
The exterior color of various equipment (unless otherwise required by the ordering party) shall be as follows: a: Sea gray or light gray (semi-gloss): used for indoor electronic equipment and console panels, cabinets and casings of electronic equipment in ships, tanks, cabins (rooms);
b Black (matte): used for various parts of equipment in aircraft cabins and on the outer surface of transformer sealed shells; C. Military green (matte): used for various parts of ground open-air equipment and exposed parts of portable electronic equipment; 10
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