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Mechanical Industry Standard of the People's Republic of China
JB/T6446-92
Vacuum Valve
Published on July 20, 1992
Technical Conditions
Implementation on January 1, 1993
Published by the Ministry of Machinery and Electronics Industry of the People's Republic of China
Mechanical Industry Standard of the People's Republic of China
Technical Conditions
Vacuum Valve扌
1 Subject Content and Scope of Application
JB/T6446-92
Replaces ZBJ78005-87
ZBJ78006-87
This standard specifies the technical requirements, test methods, inspection rules and marking, packaging, storage, etc. of vacuum valves. This standard applies to various high and low vacuum valves (hereinafter referred to as valves) in the 1×10-5～1×10*Pa vacuum system specified in JB/T4077～4080, JB/T4083 and JB/T5410. 2 Reference standards
GB6070
GB/T13306
JB1090
JB1091
JB1092
JB/T4077
JB/T4078
JB/T4079
JB/T4080
JB/T4083
JB/T5410
3 Technical requirements
Steam flow Vacuum pump Pumping rate (volume flow rate) Test method Vacuum flange
Traction Electromagnet
Type and size of rubber seal ring for J type vacuumType and size of rubber seal ring for JO type and skeleton type vacuumType and size of rubber seal ring for O type vacuumType and size of high vacuum gate valveType and basic parameters
Type and basic parameters of high vacuum flapper valve
Type and basic parameters of high vacuum butterfly valve
Type and basic parameters of high vacuum solenoid valve
Type and basic parameters of vacuum electromagnetic belt charging valveType and basic parameters of low vacuum electromagnetic pressure difference charging valveValves shall comply with the requirements of this standard and be manufactured in accordance with the drawings and technical documents approved by the prescribed procedures. 3.1
The working temperature of the valve is 5~40℃.
The valve should avoid working in an environment with corrosive gas and particulate dust. 3.4Pneumatic valves shall be equipped with accessories such as reversing valves, water distributors, constant pressure valves and oil mist collectors. 3.5
The moisture resistance index of the solenoid valve coil shall comply with the provisions of Chapter 9 of JB622. 3.6The static seal material and size of the valve shall comply with the relevant provisions of GB6070; the dynamic seal material and size shall comply with the provisions of JB1090JB1092, and the pressure resistance index of the electromagnet of the high vacuum solenoid valve shall comply with the provisions of Chapter 8 of JB622. 3.77
The connection flange type of the valve shall comply with the relevant provisions of GB6070. 3.9 When there are special requirements for the valve, the user and the manufacturer shall jointly agree 3.10 Under the condition that the user complies with the provisions of storage, use, installation, etc., the valve product shall be repaired or replaced by the manufacturer free of charge within one year from the date of shipment from the manufacturer if the product cannot work normally due to poor manufacturing quality. 4 Test method
Test items and conditions
Approved by the Ministry of Machinery and Electronics Industry on July 20, 1992 and implemented on January 1, 1993
Test items
Leakage rate;
Conductance;
Life span;
Opening and closing time of pneumatic valves.
Test conditions
JB/T6446—92
When the diffusion pump needs to be started during the test, the test should be carried out according to the test conditions specified in GB6307.1. The ambient temperature should be within the range of 15-25℃. The test process is carried out at a certain temperature within the allowable temperature and can be changed within the range of 1°℃. 4.2 Leak rate test method
4.2.1 Ammonia mass spectrometer leak detection method
4.2.1.1 Test device
The test device consists of an ammonia mass spectrometer leak detector, a leak detection platform and its vacuum system, as shown in Figure 1. 4.2.1.2 Test steps
4.2.1.2.1 Test of leak detector sensitivity (minimum detectable leak rate) 9mm Before the leak rate test of the valve to be tested, first connect the standard leak hole at the interface of the leak detection platform according to the device shown in Figure 1, and measure the sensitivity (minimum detectable leak rate) qm of the hydrogen mass spectrometer leak detector.
Valve to be tested
Work leak detection platform and its interface
Connect the leak detector
4.2.1.2.2 The overall leak rate Q of the valve The test is carried out according to the test device shown in Figure 1 and the following steps: a. Connect the valve port of the valve to be tested, which is directly sealed or opened by the valve plate, to the interface of the leak detection platform. The other flange port of the valve is sealed with a blind plate or a bell cover (for butterfly valves, etc.);
b. Open the valve plate of the valve to be tested and start the vacuum system. When the pressure in the valve body to be tested drops to 5×10-1Pa, connect the leak detector to continue to evacuate. When the pressure of the test device drops to the limit pressure or close to the limit pressure, close the valve leading to the vacuum system. Record the output signal value U of the leak detector;
C. Use a bell cover made of a dense material (such as plastic film, etc.) to tightly seal the valve to be tested and fill the cover with hydrogen. Record the stable hydrogen signal value U output by the leak detector;
JB/T6446-—92
d. Calculate the overall leakage rate Q-(=Q) of the valve under test according to the following formula: Q=(UU.)q
Wherein: Q leakage rate, Pa·L/s;
—stable hydrogen signal value output by the leak detector, mV; U.
—leak detector output signal value, mV;
leak detector sensitivity, Pa·L/(s*mV). 4.2.1.2.3 The test of the valve forward leakage rate Q. shall be carried out according to the test device shown in Figure 1 and the following steps: a. Carry out according to 4.2.1.2.2a, but the other flange of the valve is connected to the atmosphere; (1))
b. Close the valve plate of the valve under test, start the vacuum system, and test the space below the valve plate according to 4.2.1.2.2b. Record the output signal value U of the leak detector.
C. Follow 4.2.1.2.2c and record the stable hydrogen signal value Ua output by the leak detector; or use the hydrogen spraying method, extend the nozzle of the spray gun into the body of the valve to be tested, and spray hydrogen on the surface of the valve plate and around the sealing port. Record the hydrogen signal value of each leak hole and calculate their sum U=2U; d. The forward leakage rate Q (=Q) of the valve to be tested is calculated according to formula (1). 4.2.1.2.4 The test of the reverse leakage rate Q of the valve is carried out according to the test device shown in Figure 1 and the following steps: a. Close the valve plate of the valve to be tested, and connect the other flange of the valve to the interface of the leak detection platform; b. Start the vacuum system, test according to 4.2.1.2.2b, record U,; test according to 4.2.1.2.2c, record U; or use hydrogen blowing method to spray ammonia from the outside to the surface of the valve plate of the valve to be tested, around the sealing port and the outer surface of the valve. Record the hydrogen signal value of each leak hole, and calculate their sum U=U; d The reverse leakage rate Q (=Q) of the valve to be tested is calculated according to formula (1). 4.2.2 Closed leak test method
4.2.2.1 Test device
The test device consists of a mechanical pump, a vacuum valve, a pipeline, an auxiliary container, a blind plate, a fine-tuning valve, a pressure gauge, a vacuum gauge and an expansion pump, as shown in Figure 2.
Tested valve
a. The volume of the auxiliary container is stipulated as follows:
JB/T6446-92
For valves with nominal diameter D<100mm, the volume of the auxiliary container V>1L; for butterfly valves with nominal diameter D>100mm, the volume of the auxiliary container should be greater than 6 times the volume of the butterfly valve: For other valves with nominal diameter D>100mm, if their volume can meet the needs of leakage rate test, it is up to you to decide whether to install the auxiliary container;
b. When the vacuum surface of the pipeline, blind plate and auxiliary container is made of carbon steel, it needs to be chrome-plated or nickel-plated to prevent rust and reduce outgassing;
C. The instruments used for valve testing (vacuum gauge, pressure gauge and stopwatch, etc.) must be calibrated by a calibration unit recognized by the national metrology department, and the vacuum instrument needs to be calibrated with dry air. 4.2.2.2 Test process
4.2.2.2.1 The test of the auxiliary container leakage rate Q. is carried out according to the test device shown in Figure 2 and the following steps: a. The connecting pipe between the auxiliary container and the valve to be tested is separated by a blind plate at the end close to the valve to be tested; b. Start the vacuum system, and after the auxiliary container reaches the limit pressure, continue to pump air for 4 hours to fully degas the container to be pumped.Close the damper valve between the oil diffusion pump and the auxiliary container. When the pressure of the auxiliary container rises to the predetermined initial pressure P:, record the corresponding time t1. When the pressure continues to rise to the predetermined pressure p (<13Pa), record the corresponding time t, and calculate Ap=pp: and △t=ti-t. The pressure reading is taken to two significant figures.
Substitute the Ap and △t values measured three times in a row into formula (2) for calculation, and use the average value of the calculation results as the auxiliary container leakage rate Q:
-auxiliary container leakage rate, PaL/s;
Where: Q
V. —The total volume of the upper space of the damper valve installed at the air inlet of the diffusion pump and the auxiliary container and its pipeline space connected to the valve to be tested (referred to as the volume of the auxiliary container), L; Ap——pressure increment, Pa;
Time increment, 8.
4.2.2.2.2 The test of the overall leakage rate Q of the valve is carried out according to the test device shown in Figure 2 and the following steps: a. Remove the blind plate between the auxiliary container pipeline and the valve under test installed in 4.2.2.2.1a, and connect the valve port of the valve under test that can be directly sealed or opened by the valve plate to the auxiliary container. The other flange port of the valve is sealed with a blind plate or a bell cover (for media valves, etc.). Open the valve plate to make the valve under test and the auxiliary container form a connecting space; b. According to the procedure of 4.2.2.2.1b, conduct a leakage rate test on the connecting space, substitute the values of three consecutive repeated tests into formula (3) for calculation, and use the average value of the calculation results as the leakage rate Q of the connecting space: Q= V.4p
Where: Q.—leakage rate of the connecting space, Pa-L/s; V.—volume of the connecting space, L, V.=V. +V.;V.
-The volume of the valve under test, L;
c. Calculation of the overall leakage rate of the valve
The Q measured in item b above is the leakage rate measured for the connecting space. The difference between the leakage rate of the connecting space and the leakage rate of the auxiliary container is the overall leakage rate Q. of the valve when the valve plate is open:
Q.-Q.-Q...
Wherein: Q. Overall leakage rate of the valve, Pa·L/s.4.2.2.2.3 Test of the forward leakage rate Q. of the valve JB/T6446-92
Perform test calculation according to the test device shown in Figure 2 and the following steps:a. Close the valve plate, isolate the valve under test from the auxiliary container, remove the blind plate at the other flange port, and allow the valve body under test to enter the atmosphere; b. According to the procedure of 4.2.2.2.1b, test the space below the valve plate of the valve under test, substitute the test values for three consecutive times into formula (5) for calculation, and take the average value of the calculation results as the leakage rate Q of the space below the valve plate of the valve under test: Q=Vp
Where: Q. ——Leakage rate of the space below the valve plate, PaL/s; V. ——Volume of the space below the valve plate of the valve under test, L, V. =V. +V. ; ·(5)
V. ——Volume of the narrow cylindrical gap below the valve plate of the valve under test, L, starting from the lower surface of the valve plate on the cylinder to the surface that interfaces with the blind plate as referred to in 4.2.2.2.1a;
c. Calculation of valve forward leakage rate
The Q measured in item b above. is the leakage rate measured for the space below the valve plate of the valve under test. The difference between the leakage rate of the lower space and the leakage rate of the auxiliary container is the valve forward leakage rate Q when the valve plate is closed: Q.=Q.\-Q..
Wherein: Q——valve forward leakage rate, Pa·L/s4.2.2.2.4 Test of valve reverse leakage rate Q Connect the test device shown in Figure 2 and perform the test calculation as follows: ·6)
a. Install the vacuum gauge gauge on the valve under test, install the fine-tuning valve and the pressure gauge on the auxiliary container, and still seal the other flange port of the valve under test with a blind plate and open the valve plate;
b. Open the baffle valve connected to the diffusion pump to allow the auxiliary container to After the pressure of the connected space of the tested valve drops to the limit pressure, continue to pump air for 4 hours, close the flap valve and the valve plate of the tested valve, and fill the auxiliary container with atmosphere or gas of required pressure through the fine-tuning valve according to the relevant design regulations. Then, according to the relevant provisions of the procedure in Article 4.2.2.2.1b, repeat the test of the upper space of the valve plate in the tested valve body by opening and closing the flap valve, substitute the three consecutive repeated test values into formula (7) for calculation, and take the average value of the calculation results as the valve reverse leakage rate Q when the valve plate is closed:
Where: Q.--valve reverse leakage rate, Pa·L/s; V. Volume of the upper space of the valve plate in the tested valve body, L. 4.3 Conductance test method
4.3.1 Test device
· (7)
According to GB6307.1, the device consists of a mechanical pump, pipeline, valve, oil diffusion pump, test cover, vacuum gauge, fine-tuning valve and flow device as shown in Figure 3. wwW.bzxz.Net
4.3.2 Test steps
4.3.2.1 Test of effective pumping speed of oil diffusion pump and its system 4.3.2.1.1 When the nominal diameter of the tested valve is the same as the inlet inner diameter of the oil diffusion pump, the test cover is directly connected to the diffusion pump, and the effective pumping speed U of the diffusion pump is measured according to GB6307.1. 4.3.2.1.2 When the nominal diameter of the tested valve is different from the inlet inner diameter of the oil diffusion pump, the test cover is connected to the diffusion pump through a tapered tube or a transition flange, and the effective pumping speed U of the diffusion pump system is measured according to GB6307.1: 5
4.3.2.2 Test and calculation of valve conductance
JB/T6446—92
The tested valve
is connected to the flow device
In 5. After the test procedure in Article 2.1 is completed and the vacuum system is stopped and cooled sufficiently, the valve under test is connected between the diffusion pump and the test cover. The pumping speed U of the diffusion pump system with the valve under test as a component is measured in accordance with GB6307.1. U represents the flow conductance of the valve under test, then 11
—molecular flow conductance of the valve, L/s;
wherein: U
U,-—effective pumping speed of the oil diffusion pump or diffusion pump system, L/s; ·(8)
—effective pumping speed of the oil diffusion pump or diffusion pump system equipped with the valve, L/s. The average pumping speed is calculated by taking the pressure range value according to the horizontal parallel section of its pumping speed curve and the pumping speed curve of 0
U,. The low-pressure end point is appropriately moved inward to offset the influence of ignoring the limit pressure in the pumping speed calculation formula on the calculation result.
4.4 Life test method
4.4.1 Device and principle
The valve to be tested is tested on the life test bench, and the control system is used to operate the automatic operation of the life test. The counter is used to test and record the number of times the valve is opened and closed. The opening and closing frequency should comply with the following regulations. 4.4.1.1 High vacuum butterfly valve: The test can be carried out in a vacuum state or in the atmosphere, and the test frequency is at least 3 times/min for Φ32~160mm; 1~2 times/min for medium 200~800mm.
4.4.1.2 High vacuum solenoid valve: The test is carried out in a vacuum state, and the test frequency is 8 times/min for Φ10~80mm; 4 times/min for Φ100~200mm. The valve should be placed vertically during the test. 4.4.1.3 Vacuum electromagnetic belt inflation valve, low vacuum electromagnetic pressure difference inflation valve: the test is carried out under vacuum state, the test frequency is 4 times/min for Φ1040mm; 2 times/min for Φ50~200mm, and the pressure difference valve should be placed vertically during the test. 4.4.1.4 High vacuum plug plate: the test can be carried out in vacuum state or in the atmosphere, the test frequency is 2 times/min for Φ320mm or less; 1 time/min for Φ400~630mm; 0.5 times/min for Φ800mm or more in: 4.4.1.5 High vacuum flapper valve: The test can be carried out in vacuum or in the atmosphere. The test frequency is 2 times/min for diameters below 320mm, 1 time/min for diameters between 400 and 630mm, and 0.5 times/min for diameters above Φ800mm: 4.4.2 Test steps
4.4.2.1 Predict at 1/2 and 3/4 times of the life index. After each prediction, other valve properties must be tested to determine changes in valve performance. Finally, test according to the life index. According to the needs of the test work, after predicting at 1/2 times and 3/4 times of the life index, 7/8 times, 15/16 times, etc. can be arranged for prediction, but the difference between the opening and closing times between two consecutive times shall not be less than 10% of the life index. 4.4.2.2 After the high vacuum solenoid valve is tested according to the maximum operating frequency index, other valve performances must be tested to determine the index. 4.5 Opening and closing time test method
The opening and closing time values of the valve are directly measured by the timer. 5 Inspection rules
5.1 Products must be inspected and qualified by the technical inspection department of the manufacturer, and can only be shipped with a product quality certificate. 5.2 Products should undergo factory inspection and type inspection. 5.3 Factory inspection
Factory inspection should be carried out on each unit, and its items include: appearance quality;
b.Opening and closing action;
c. Leakage rate.
5.4 Type inspection
5.4.1 Type inspection shall be carried out when any of the following conditions are met: new products to be trial-produced;
when the product is put into production again after being discontinued for two years;
when the product is transferred to another factory for production;
when there are major changes in the product manufacturing process or materials used, which affect the product quality; e.
when the quality supervision department inspects.
5.4.2 Type inspection: 5% of the batch products shall be sampled for inspection, but not less than 2 units; if the products fail to meet the standards, double sampling shall be conducted; if the products fail to meet the standards again, the whole batch of products shall be inspected one by one.
5.4.3 Type inspection items include:
Appearance quality;
Opening and closing actions;
Leakage rate;
d. Flow conductance;
Opening and closing time of pneumatic valves,
6 Marking, packaging and storage
6.1 Each valve shall be fixed with a product nameplate in a conspicuous position. The type, size and technical requirements of the nameplate shall comply with the provisions of GB/T13306. The content of the nameplate shall include:
a. Name of the manufacturer of the product;
b. Name and model of the product;
C. Nominal diameter of the product;
d. Product number and manufacturing date.
6.2 The packaging of the valve should be safe and firm, and the sealing surface should be protected from damage. The inside of the valve body should be kept clean to prevent rust and damage. The accessories, spare parts and packing documents of the product should be prevented from damage and loss: 6.3 The product should be stored in a dry room at a storage temperature of 5-40°C. It is not allowed to be stored in the open air to prevent the sealing ring from freezing or aging. 6.4 When each valve product is packed at the factory, the instruction manual, certificate of conformity and packing list should be placed in a waterproof document bag. 7
Additional instructions:
JB/T6446-92
This standard was proposed by the National Vacuum Technology Standardization Technical Committee. This standard was drafted by the Shenyang Vacuum Technology Research Institute of the Ministry of Machinery and Electronics Industry. The main drafter of this standard is Zhang Zheng Entao.
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