JB/T 6996-1993 General technical requirements for hydraulic systems of heavy machinery
Some standard content:
Mechanical Industry Standard of the People's Republic of China
JB/T6996-1993
Heavy Machinery Hydraulic System
General Technical Conditions
Published on September 3, 1993
Ministry of Machinery Industry of the People's Republic of China
Implemented on July 1, 1994
Mechanical Industry Standard of the People's Republic of China
Heavy Machinery Hydraulic System
General Technical Conditions
Subject Content and Scope of Application
JB/T6996-1993
This standard specifies the general technical conditions for the hydraulic system of mechanical equipment such as metallurgy, rolling and heavy forging (hereinafter referred to as mechanical equipment). The hydraulic system of the above mechanical equipment (hereinafter referred to as the system) can be specified according to the principles of this standard and combined with relevant standards, and the corresponding technical requirements for design, manufacturing and acceptance can be supplemented. This standard applies to the hydraulic system of mechanical equipment with a nominal pressure not exceeding 31.5MPa. 2
Cited standards
GB2876
GB3766
GB4879
GB5083
GB/T13384
JB/ZQ4000.1~4000.10
JB/ZQ4286
JB/ZQ4396
JB/ZO4398
General requirements
Basic requirements
Personnel safety:
Safe and reliable work;
Normal operation:
Energy saving and high efficiency;
Low noise;
No leakage:
Simple and perfect principle:
Easy maintenance;
Packing, storage and transportation diagram Mark
Oil tank capacity series of hydraulic pump station
General technical conditions for hydraulic system
Rust-proof packaging
General principles for safety and sanitation design of production equipment
Classification of lubricants and related products (Class L)
Part 2: Group H (hydraulic system)
General technical conditions for packaging of electromechanical products
General technical conditions
General technical conditions for packaging
Pipeline groove and pipe fixing
Hose laying specification
Aircraft hydraulic system contamination test Method for collecting liquid samples on system pipelines Seamless steel pipe
Approved by the Ministry of Machinery Industry of the People's Republic of China on September 3, 1993 and implemented on July 1, 1994
i. Long system life:
j. Low cost.
3.2 Design conditions
JB/T6996-1993
The technical agreement and (or) design task book must clearly state the following: a. The main purpose of the mechanical equipment:
b. The process flow, action and cycle of the mechanical equipment: c. The climate conditions in the area where the system is used. The ambient temperature, humidity and their range of variation around the system; d. The installation location of the hydraulic actuator, hydraulic pump station, hydraulic valve station (group, rack) and other hydraulic devices [such as indoor or outdoor installation: installation on fixed mechanical equipment or mobile mechanical equipment: installation in the basement, ground level or elevated (layer), etc.]. If necessary, the layout of mechanical equipment should be provided:
e. The highest inlet water temperature, water quality and water supply pressure of cooling water in the water cooling system; f. For high dust, high temperature, strong radiation, easy to corrode, flammable (explosive) environment: external disturbance (such as impact, vibration, etc.): high altitude (above 1000m); severe cold areas and system design, manufacturing and use requirements under special conditions such as high precision and high reliability; g. The force and motion parameters of the hydraulic actuator; installation method and related special requirements (such as pressure maintenance, pressure relief, synchronization accuracy and dynamic characteristics, etc.):
h. The degree of automation and interlocking requirements of system operation; i. The type of working oil (liquid) used in the system j. Clearly define the user's power grid parameters.
3.3 Safety requirements
The design of the system should take into account various possible accidents. The function setting of the system, the selection, application, configuration and adjustment of components, etc., should first consider the safety of personnel and the minimum damage to equipment when an accident occurs. 3.3.1 There must be overpressure protection in the system.
The design and adjustment of the system must minimize the impact pressure. The impact force will not affect the normal operation of the equipment and cause danger. 3.3.3
The design of the system should take into account the loss of pressure and loss of control (such as accidental power failure, etc.) to prevent the hydraulic actuator from producing uncontrolled movement and causing danger. 3.3.4
The use of components must comply with the corresponding use characteristics, technical parameters and performance. The installation position of the components must be safe and convenient for adjustment and operation. 3.3.5
The operation and adjustment of components must comply with the regulations of the manufacturer. 3.3.6
3.3.7The system design should comply with relevant safety technical standards such as GB5083 and industrial hygiene regulations. 3.4 Energy saving requirements
When designing the system, consideration should be given to improving the system efficiency (such as using energy-saving components, energy-saving circuits, etc.) to minimize the heating of the system. 3.5 Working temperature
3.5.1 The temperature range of the system's working oil (liquid) must meet the use requirements of the components and oil. 3.5.2 To ensure the normal working oil (liquid) temperature, a heat exchange device should be installed according to the use conditions or the heat exchange capacity of the oil tank itself should be improved to control its temperature within the specified requirements. Under normal circumstances, the oil temperature at the suction port of the hydraulic pump shall not exceed 60°C, and the liquid temperature shall not exceed 40°C. The system must be able to work normally at the lowest temperature specified in the design. 3.6 Pipeline flow rate
The recommended value of the oil flow rate of the metal pipeline of the system is shown in Table 1.2
3.7 Noise
JB/T6996-1993
3.7.1 When designing the system, measures should be taken to reduce noise, and the system noise should comply with the provisions of relevant standards. 3.7.2 In special cases, hydraulic pump stations with noise exceeding the standard should be installed in isolation. 3.8 Selection basis
3.8.1 All components, auxiliary components, seals and fasteners in the system should comply with the relevant standards or the product drawings and technical documents approved for production by relevant departments. 3.8.2 The quality of purchased parts shall comply with the relevant standards and the provisions of the approved product drawings and technical documents, and must have a certificate of conformity for the corresponding quality level.
3.8.3 Important purchased parts must be inspected and accepted according to performance requirements. 3.8.4 Purchased parts that may affect product quality due to rust, damage, deformation, etc. during storage, transportation, and system assembly shall not be put into use. Table 1
Pipeline type
Oil suction pipeline
Oil pressure pipeline
Oil return pipeline
Oil drain pipeline
Pipeline code
3.8.5 Purchased parts with seal failure or contamination must be replaced and cleaned before use. 3.9 Cleanliness Control
Allowable Flow Rate
3.9.1 The cleanliness of components and auxiliary components shall comply with the relevant standards or specifications, and their cleanliness shall be maintained during the system assembly process. 3.9.2 Metal burrs on oil blocks, joints, metal pipe ports, and metal burrs at the intersection of the internal channels of the oil blocks must be removed. Steel plates and steel pipes must be derusted and shall comply with the provisions of Article 5.2b of this standard. 3.9.3
3.9.4 Before assembling the system, joints, pipelines, channels (including casting core holes, drilled holes, etc.) and oil tanks must be cleaned according to relevant process specifications. No visible contaminants (such as iron filings, fibrous impurities, welding slag, etc.) are allowed to exist, and their cleanliness shall be maintained. 3.9.5 The assembled system shall be flushed. Flushing requirements shall comply with Chapter 14 of this standard and relevant cleaning specifications. 5 To prevent the system from being polluted, an air filter should be installed in the open oil tank: an oil filter should be installed in the system circuit; a non-bypass oil filter should be installed at the pressure port of the servo valve and proportional valve. 3.9.7 The new oil (liquid) injected into the system must be filtered, and the filtering accuracy must not be lower than the design requirements. 3.10 Manufacturing basis
The system manufacturing should comply with the agreement between the supply and demand parties, and should comply with the design drawings, technical documents and relevant standards and process specifications reviewed, approved and effective by relevant units.
3.11 Basic requirements for maintenance
3.11.1 The components should be located in a place where they can be easily disassembled and assembled, and there must be enough space for easy maintenance. 3
JB/T6996—1993
3.11.2 When the components in the system are disassembled, the working oil (liquid) must not be lost in large quantities, and the disassembly of adjacent components and parts should be minimized, and the oil tank is not required to be drained.
3.11.3 If the use and installation conditions permit, the system should be equipped with an oil pan. 3.11.4 While meeting maintenance conditions, the number of disassembled and assembled parts of the system pipeline should be as small as possible. The pipeline laying position should be convenient for assembly and disassembly, and should not hinder the walking of production personnel and the maintenance and overhaul of electromechanical equipment. 3.11.5 Large hydraulic devices should be equipped with facilities such as racks or escalators. 5 The system should be equipped with necessary pressure measurement points, exhaust points, working oil (liquid) sampling points, refueling ports and oil drain ports. 3.11.6
3.11.7 If the hydraulic device has electrical wiring, a junction box should be installed. 3.12 Lifting measures
All components and parts weighing more than 15kg must be able to be easily lifted or equipped with lifting devices. 3.13
Installation, use and maintenance information
The design unit must provide the user with the civil engineering task book of the system. 3.13.1
The design unit must provide the user with the following drawings and materials: a.
System schematic diagram, including a list of component models, names, specifications, quantities and manufacturers; b. System electrical and (or) mechanical control component operation time schedule; System equipment installation diagram or other drawings specified in the agreement; c.
Spare parts list.
The design unit must provide the user with a system instruction manual, which mainly includes: the main purpose of mechanical equipment;
b. The main function, composition and main technical parameters of the system; the working principle and instructions for use of the system;
d. Conditions and requirements for normal operation of the system [such as normal operating oil (liquid) temperature range; oil cleanliness requirements; oil tank filling height; oil type code and working viscosity range; oil (liquid) requirements, etc.]; e
System debugging methods, steps, operating requirements and precautions; f.
The location of test points, refueling ports, oil drain ports, sampling ports, oil filters, etc. for regular testing and maintenance: common system faults and troubleshooting methods, and maintenance methods for special components and parts; g
h. Storage conditions and storage period of seals; list of tools and consumable seals (excluding purchased seals) that come with the equipment. i.
Acceptance data
The system assembly factory test outline and acceptance technical documents should be formulated by the design unit or agreed upon by the user, the manufacturing unit and the design unit, and mainly involve the following contents:
The purpose, requirements, conditions, methods, steps and precautions of the test; a.
b. Pressure resistance test and record sheet;
Oil cleanliness sampling test report:
d. System loop function test and record sheet;e
System component running-in test and record sheet;
System loop static and dynamic performance test (such as pressure holding, speed regulation, synchronization, positioning and regulation accuracy, etc.) and record sheet;f.
gSystem mark calibration and record sheet:
h. System noise detection and record sheet.
5 Marking
3.15.1 Schematic Diagram Marking
JB/T 6996—1993
1 The graphic symbols of components shall comply with the provisions of relevant standards or samples of professional component manufacturers. 3.15.1.2 The measurement units shall comply with national standards. 3.15.1.3
Hydraulic actuators shall be represented by schematic diagrams and marked with names. The corresponding hydraulic cylinder or hydraulic motor shall be marked with specification parameters and oil port size.
3. 15. 1. 4
The main pipeline (such as pressure pipeline, return pipeline, drain pipeline, etc.) and the pipeline connecting the hydraulic actuator shall be marked with the pipeline outer diameter and wall thickness.
3.15.1.10
3.15.1. 11
Pressure control components shall be marked with pressure setting values. Pressure inflation components or parts shall be marked with inflation pressure. Temperature control components shall be marked with temperature setting values. Motors, electrical contacts and electromagnetic coils shall be marked with codes. Each component shall be assigned a digital part number, and components of the same model shall also be marked with their arrangement sequence number. The hydraulic circuit constituting an independent hydraulic device shall be divided into areas and marked with codes using double-dotted lines. The interfaces between the various assembled components within the system shall be marked with codes. 3.15.2
Equipment marking
When marking components or other items on system equipment, the marking must be consistent with the marking on the drawing. 3.15.2.1 The main pipelines of the pressure oil pipeline, return oil pipeline and drain oil pipeline shall be marked with "P", "O" and "L" respectively. The pipelines connected to the hydraulic actuators shall be marked with pipeline codes. 3.15.2.2 The component interfaces in the system shall be marked with codes (such as oil port codes) as specified by the component manufacturers. 3 Hydraulic operating devices (such as manual, foot pedal, electric control valves and components, etc.), pressure gauges and other parts shall be marked with functional symbols. 3.15.2. 3
3.15.2.4 The outlet connection of the main pipeline of the hydraulic device (such as pressure oil pipeline, return oil pipeline, drain oil pipeline) shall be coated with a 100mm wide color ring topcoat. It is used to indicate pipelines of different functions. The coloring shall comply with the design requirements. The paint color of the main pipe on the non-hydraulic device should correspond to and be the same as the color ring. 3.15.2.5
The wiring of the junction box on the hydraulic device should be marked with the line number. The hydraulic device should be marked with the product nameplate, and the purchased components must be accompanied by a nameplate. 3.15.2.7 The hydraulic pump should be marked with the pump shaft rotation direction mark 3.15.3 Marking requirements
The markings on the hydraulic device must be eye-catching, clear, durable and regular. The printing, spraying, pasting and binding positions of the markings must not lose the markings after replacing the components.
3.16 Operating force
When designing, the force on the manual and foot control mechanisms should not exceed the following values: fingers
single arm
double arm 250N
foot pedal 78N
3.17 Tightening torque
JB/T6996-1993
The tightening torque of joints, plugs, and component fasteners should comply with relevant specifications or the regulations of the manufacturer. 4 Hydraulic oil (liquid)
4.1 Basic requirements
4.1.1 The type and characteristics of the hydraulic oil (liquid) specified for use in the system must be stated. 4.1.2 For the selected hydraulic oil (liquid), the compatibility with the following substances must be considered when designing the system: metal materials, seals and other non-metallic materials in contact with the hydraulic oil (liquid) in the system. a.
b. Protective coating materials and other liquids that may be related to the system, such as paint, treatment fluid, anti-rust oil (liquid) and maintenance oil;
C Materials in contact with overflowed or leaked hydraulic oil (liquid), such as relays, wires, etc. 4.2 When using hydraulic fluid as a transmission medium, the general components used in the system should be considered for derating (such as pressure, speed, etc.). 4.3 The use of hydraulic oil (liquid) in the system should comply with GB7631.2 and the regulations of relevant oil (liquid) professional manufacturers, and consider its temperature, pressure range of use and its particularity.
4.4 Matters to be noted during the use of hydraulic oil (liquid) 4.4.1 Within the temperature range of the working oil specified by the system, the viscosity range of the selected oil should meet the use conditions of the components. 4.4.2 Different types of hydraulic oil (liquid) should not be mixed with each other, and the same brand of hydraulic oil (liquid) produced by different manufacturers should generally not be mixed. If mixed, a small sample mixing test must be carried out to check whether there are physical changes and chemical reactions. If necessary, it should be negotiated and confirmed with the oil manufacturer.
4.4.3 During use, the physical and chemical indicators and cleanliness of the hydraulic oil (liquid) must be regularly inspected to determine whether the hydraulic oil (liquid) can be used again. Generally, it should be inspected once every 3 months, and the longest time should not exceed 6 months. 4.5 Maintenance of hydraulic oil (liquid)
The viscosity, acid value, moisture, cleanliness and other qualities of the oil in the system must be checked regularly. If they do not meet the quality requirements, they should be replaced completely.
4.6 Others
The supplier of hydraulic oil (liquid) must provide information on the labor hygiene requirements for personnel when using hydraulic oil (liquid), the dangers of toxic gases and suffocation generated in the event of a fire, and waste liquid treatment issues. 5 Quality of castings, forgings, welded parts and pipe fittings 5.1 Basic requirements
5.1.1 The brand of metal materials should meet the requirements of the drawings. 5.1.2 The chemical composition and mechanical properties of metal materials must meet the requirements of relevant standards. 5.1.3 The quality of castings, forgings, weldments and pipe fittings shall comply with the relevant standards. 5.2 Welded parts and pipe fittings shall meet the following requirements: a. The metal surface rust degree of welded parts (plates, profiles, etc.) shall not be lower than Class B, and the metal surface rust degree of hydraulic pipe fittings shall not be lower than Class A (see Appendix A of JB/ZQ4000.10): 6
JB/T6996-1993
b. Welded parts and pipe fittings must be derusted, and the quality of derusting shall comply with the provisions of JB/ZQ4000.10. After derusting, antirust shall be carried out according to the relevant standards and specifications:
C. The molding shape tolerance of welded parts shall comply with the provisions of JB/ZQ4000.3: d.The cross-sectional surface roughness R value of the welding bad material is 25um: e. The end face of the pipe fittings shall not have an extruded shape, the end face shall be flush, and the verticality tolerance with the pipe axis shall be 1% of the outer diameter of the pipe: f. The welding groove of the welding bad material and pipe fittings shall be machined and comply with the relevant standards. 5.3 The welding joint form of the welded parts shall comply with the relevant standards. 5.4 The inner wall of the pipeline welding interface shall be flush: for pipes with a working pressure lower than 6.3MPa, the inner wall misalignment shall not exceed 2mm: for pipes with a working pressure equal to or higher than 6.3MPa, the inner wall misalignment shall not exceed 1mm5.5 For defects in castings and forgings that do not affect the use and appearance, welding repair is allowed in accordance with relevant standards and regulations under the condition of ensuring the quality of use.
6 Welding requirements
6.1 Basic requirements
6.1.1 The welding of welded parts and pipelines shall be carried out in accordance with relevant standards and processes. 6.1.2 The quality of pipeline welds shall comply with BS and BK grades (see JB/ZQ4000.3). 6.1.3 Oil tanks (tanks) and pipelines shall be subjected to leakage or pressure tests in accordance with relevant standards. 6.2 Welding of oil tanks (tanks)
6.2.1 The inner wall of an open rectangular oil tank shall be welded with full continuous welds. The inner wall weld of an open cylindrical oil tank (tank) shall be higher than the inner wall, and the height shall comply with relevant standards.
6.2.2 The design and welding of pressure oil tanks (tanks) shall comply with relevant standards for pressure vessels. 6.2.3 When a painted oil tank is re-welded, the coating on the inner wall of the oil tank shall be prevented from falling off. 6.3 Pipeline welding
Steel pipes shall be welded with argon arc welding or argon arc welding backing arc welding filling welding. 6.3.2
For butt welding of pipelines, the weld of the inner wall shall be higher than the inner wall, and its height shall comply with the provisions of JB/ZQ4000.3. 6.3.3
Technological measures shall be formulated for the repair of pipeline welds, and the number of weld repairs at the same location shall not exceed 2 times. 6.3.4
When welding pipelines, the sealing rings in the welding hot zone shall be removed to avoid overheating and aging. 7 Processing quality
7.1 Sharp edges and corners without reservation requirements shall be chamfered and blunted. 7.2 There shall be no rust, burrs, bumps, scratches and other defects on the machined surface. 7.3 For machined parts whose tolerance requirements are not specified in the drawings, their dimensional deviations, geometric tolerances and thread accuracy shall comply with the standard grades specified by the manufacturer.
8 Leakage
When the system is operating at the upper limit of normal working oil temperature within the specified service life, the seals of all pipelines, components, detachable joints, and movable connections should be well sealed and there should be no leakage of oil. 7bZxz.net
9 Hydraulic actuators
9.1 Hydraulic cylinders
JB/T6996-1993
9.1.1 When designing or selecting hydraulic cylinders, full consideration must be given to the stroke, load and assembly conditions to prevent abnormal bending of the piston rod when it is extended.
9.1.2 The installation of hydraulic cylinders must comply with the design drawings and (or) the regulations of the manufacturer. 9.1.3
When installing hydraulic cylinders, if the structure allows, the oil inlet and outlet must be located at the top. It must be installed so that it can be automatically deflated or equipped with a convenient deflation valve.
9.2 Hydraulic motor
9.2.1 The type and installation requirements of the coupling between the hydraulic motor and the driven device shall comply with the manufacturer's regulations. 9.2.2 The exposed rotating shaft and coupling must be covered with protective covers. 9.2.3 When applying the hydraulic motor, the influence of its starting torque, stall torque, load change, load kinetic energy and low speed must be considered.
9.3 Mounting base
The mounting base of the hydraulic actuator must have sufficient rigidity to ensure the normal operation of the actuator. 10 System equipment assembly
10.1 Hydraulic pump device
The type and installation requirements of the coupling between the hydraulic pump and the prime mover must comply with the manufacturer's regulations. 10.1.1
The exposed rotating shaft and coupling must be equipped with protective covers. 10.1.22
The mounting base of the hydraulic pump and the prime mover must have sufficient rigidity to ensure that they are always coaxial during operation. 10.1.3
10.1.4 The oil inlet pipeline of the hydraulic pump should be short and straight, avoiding too many bends and sudden changes in the cross section. Within the specified oil viscosity range, the oil inlet pressure and other conditions of the pump must meet the specified values of the pump manufacturer. 10.1.5
The oil inlet pipeline of the hydraulic pump must be sealed reliably and air must not be sucked in. It is recommended that the oil inlet of the pump be equipped with a rubber elastic compensating pipe. a.
The oil outlet of the pump is connected to a high-pressure hose;
The base of the pump device is equipped with an elastic shock-absorbing pad.
10.2 Oil tank device
10.2.1 Oil tank
The design of the oil tank shall meet the following basic requirements: 10.2.1.1
a. The nominal capacity of the oil tank shall comply with the provisions of GB2876; b. Under normal working conditions of the system, especially when no cooler is installed in the system, it must be able to fully dissipate the heat in the hydraulic oil (liquid);
It should have a slower circulation speed to precipitate the air mixed in the oil and precipitate the heavier impurities in the oil; c.
d. The oil return port of the oil tank should be far away from the oil inlet of the pump, and can be isolated by a baffle or other measures, but it must not hinder the cleaning of the oil tank;
e. Under normal working conditions, it must accommodate all the hydraulic oil (liquid) flowing from the system. 8
10.2.1.2 Fuel tank materials
General fuel tanks should be made of carbon steel plates,
JB/T6996-1993
Important fuel tanks and special fuel tanks can be made of stainless steel plates. 10.2.1.3 The structure of the fuel tank should meet the following basic requirements: a. The fuel tank must have sufficient strength and rigidity to avoid large deformation after installing various components and filling with oil: b. The bottom of the fuel tank should be more than 150mm higher than the installation surface to facilitate moving, draining oil and heat dissipation: There must be enough supporting area to adjust with gaskets and wedges during assembly and installation: c.
d. The inner surface of the fuel tank should be kept flat, with fewer structural parts, so as to clean the internal dirt: e. In order to clean the oil tank, one or more hand holes and manholes should be configured: the shape of the bottom of the oil tank must be able to drain the hydraulic oil (liquid) completely, and an oil drain port should be set at the bottom; f.
The hand holes and manholes on the oil tank cover, side walls, and the holes or base plates for installing other components should be welded with boss flanges (such as blind g.
hole flanges, through-hole flanges, etc.):
h. The structure of the removable cover must be able to prevent impurities from entering the oil tank; i. The pipes passing through the oil tank wall should be effectively sealed. 2 Requirements for the installation of oil tank accessories
10.2.2.1 Important oil tanks should be equipped with oil diffusers or defoaming devices. 10.2.2.2 An air filter and an oil (liquid) injector should be installed on the top of the open oil tank. The filtration accuracy of the air filter should meet the system cleanliness requirements. The maximum pressure loss of the air filter should not affect the normal operation of the hydraulic system. 10.2.2.3 The oil tank must be equipped with a level gauge, which should be placed near the hydraulic pump suction port to display the oil tank liquid level. Important oil tanks should be equipped with a level switch to monitor and send signals for the high and low limit levels of the oil tank. 10.2.2.4 The oil tank should be equipped with an oil thermometer and an oil temperature detection element to visually observe the oil temperature and send signals for the oil temperature setting value. 10.2.2.5 A low pressure alarm should be installed on a pressure-isolated oil tank, and a pneumatic safety valve, a pressure gauge and a pressure alarm should be installed on a pressure-inflated oil tank.
10.3 Other accessories and requirements
10.3.1 Heat exchanger
The system should be equipped with a heater or cooler according to the use requirements and should meet the following basic requirements: a. The surface dissipation power of the heater shall not exceed 0.7W/cm; b. The position of the heater installed on the oil tank must be lower than the lower limit liquid level of the oil tank; when using a heat exchanger, there should be temperature measurement points for the hydraulic oil (liquid) and the cooling (or heating) medium: c.
d. When using a heat exchanger, an automatic temperature control device can be used to keep the temperature of the hydraulic oil (liquid) within the normal working range: e.
The user must use the cooling medium specified by the manufacturer. If a special cooling medium or water is used and the water source is very dirty, the water quality is corrosive, or the water volume is insufficient, it must be reported to the manufacturer; f. When using an air cooler, the air inlet and outlet passages should be prevented from being blocked or blocked. 10.3.2 Oil filter
10.3.2.1 In order to eliminate harmful impurities in hydraulic oil (liquid), the system must be equipped with an oil filter, and the filtering accuracy of the oil filter should meet the use requirements of the components and the system.
10.3.2.2 In order to indicate when the oil filter needs to be cleaned and the filter element replaced, a contamination indicator or a test device must be installed9
JB/T6996-1993
10.3.2.3 When the user specifically requests that the filter element can be replaced without stopping the system, the user's requirements should be met. 10.3.2.4 The oil inlet of the hydraulic pump can be equipped with an oil suction filter according to the use requirements. It is recommended to use a mesh bypass type. The capacity selection and installation of the oil suction filter should make the pump inlet pressure of the cold start meet the provisions of Article 10.1.4. 10.3.2.5 If a magnetic oil filter is used, the adsorbed impurities should be prevented from falling into the oil during maintenance and use. 10.3.2.6 When using an oil filter, its nominal flow rate shall not be less than the actual flow rate of the filtered oil, and there should be a certain surplus. 10.3.2.7 For large hydraulic pump stations that work continuously, it is recommended to use a separate cooling circulation filtration system. 10.3.3 Accumulator
Elements for releasing and cutting off the liquid in the accumulator should be set in the circuit of the accumulator. For inflation, maintenance or long-term shutdown.
10.3.3.2 When the accumulator is used as the hydraulic oil source, a one-way valve should be installed between it and the hydraulic pump to prevent the pressure oil in the accumulator from flowing back and causing the pump to run in the opposite direction when the pump stops working.
When the mechanical equipment stops working, if the system still uses the pressurized liquid in the accumulator to work, the safety instructions for use must be displayed in a conspicuous place near the accumulator, which should include the words "Caution, pressure vessel". 10.3.3.4 The discharge rate of the accumulator must be consistent with the system use requirements and must not exceed the manufacturer's specified value. 5 The type of gas for charging and installation of the accumulator (including gas-loaded accumulators) must comply with the manufacturer's regulations. 10.3.3.5
The installation location of the accumulator must be away from heat sources. The accumulator must not be disassembled before depressurization, and welding, riveting or machining on the accumulator is prohibited. 10.3.3.7
10.3.4 Pressure gauge
The range of the pressure gauge should generally be 1.5 to 2 times the rated pressure. When using a pressure gauge, a pressure gauge switch and a pressure damping device should be set to facilitate maintenance, accurate detection and extend service life. 10.3.5 Seals
The material of the seal must be compatible with the medium it contacts. 10.3.5.1
2The operating pressure, temperature and installation of the seal shall comply with the relevant standards. 10.3.5.2
The seals that come with the machine can be used within one year of storage under the storage conditions specified by the manufacturer. 10.4 Installation of hydraulic valves
The installation method of the valve shall comply with the manufacturer's regulations. 10.4.1
The plate valve or cartridge valve must have correct orientation measures. 10.4.2
In order to ensure safety, the installation of the valve must take into account the effects of gravity, impact, and vibration on the main parts of the valve. 10.4.3
The performance level of the valve connecting screws must meet the requirements of the manufacturer and must not be replaced at will. 10.5 Oil block
10.5.1 It is recommended to use No. 35 or No. 45 forged steel for the oil block and perform tempering treatment. 2 The quality of the machined surface of the components installed on the oil block must comply with the regulations of the component manufacturer. 10.5.2
10.5.3 The dimensional tolerance between the screw holes of the components installed on the oil block must ensure the interchangeability of the valve. 10.5.4 The oil channel in the oil block must be within the entire operating temperature and system flow capacity range so that the pressure drop caused by the fluid flowing through the channel will not have an adverse effect on the efficiency and response of the system. 10
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.