Some standard content:
Mechanical Industry Standard of the People's Republic of China
JB/T7374-94
Technical Conditions for Pneumatic Air FiltersbzxZ.net
Published on 1994-07-26
Ministry of Machinery Industry of the People's Republic of China
Implementation on 1995-07-01
Mechanical Industry Standard of the People's Republic of China
Technical Conditions for Pneumatic Air Filters
1 Subject Content and Applicable Model
This standard specifies the technical requirements, test methods, inspection rules and marking, packaging and storage of air filters. This standard applies to air filters that remove major pollutants by physical methods. 2 Reference standards
GB2346
Hydraulic and pneumatic systems and components-Nominal pressure series JB/T6378 Technical conditions for pneumatic reversing valves
3 Terms
3.1 Air filter
Air filter is a pneumatic component that retains the main solid and liquid pollutants in the compressed air. 3.2 Filtration degree
Filtration degree refers to the maximum diameter of the filter element through which solid dirt can pass. 3.3 Water separation efficiency
JB/T7374-94
Water separation efficiency refers to the percentage of the ratio of the separated water volume to the water supply volume of the air filter under the specified pressure drop (or flow rate). 4 Specifications
Specifications are divided by diameter and should comply with the provisions of Table 1. Table 1
Nominal diameter d
English in
5 Technical requirements
5.1 Working conditions
5.1.1 Working medium
Preliminary treated compressed air.
5.1.2 Medium temperature and environmental accuracy
Medium temperature and environmental temperature are both 5~60℃. 5.1.3 Nominal pressure
The nominal pressure of the air filter is selected as 0.63, 1.00, and 1.60MPa. 5.2 Performance requirements
5.2.1 Sealing
Under nominal pressure, the air filter should have no external leakage. Approved by the Ministry of Machinery Industry on July 26, 1994
M27×2
M33×2
Implemented on July 1, 1995
5.2.2 Pressure resistance
JB/T 737494
Under 1.5 times the nominal pressure, any part (component) of the air filter should have no damage or permanent deformation. 5.2.3 Filtration degree
The filtration degree of the air filter is selected according to 1, 5, 10, 25, 40, 75μm. 5.2.4 Water separation efficiency
The water separation efficiency of the air filter shall not be less than 80%. 5.2.5 Pressure drop-air volume
The air flow rate of the air filter under various inlet pressures is shown in Table 2. Its value should be measured when the outlet pressure drop reaches 5% of the inlet pressure. Its parameter value is divided into two grades, A and B. The product is tested according to the specified grade and shall not be less than the specified value in Table 2. Table 2
Nominal diameter d
Inlet pressure
Pressure drop-air flow rate (under standard conditions) m/h
Note, ①The flow rate value when the inlet pressure is greater than 1.00MPa is given by the manufacturer. A
408.0285.6
②The above flow rate is the flow rate when the filtration accuracy of the Yugang sintered filter element is 75m. The flow rate of the filter equipped with other elastic materials and precision filter elements is given by the manufacturer.
5.2.6 Drain performance
The air filter should be equipped with a manual or automatic drain. 5.2.6.1 The manual drainer should be flexible to open and close, and can drain when opened and not leak when closed. 5.2.6.2 The automatic drainer should not leak when closed, and can automatically drain when the liquid level reaches a predetermined height under the specified pressure. It should automatically close after draining and be equipped with a manual drain device. 5.2.7 Appearance quality
The surface coating of the air filter should be uniform in color, without defects such as bubbling and falling. The plastic water storage cup should not have ripples that affect transparency, and no bubbles or other debris. The label should be clear, without falling and warping. 6 Test method
6.1 Test parts
6.1.1 Test medium
Compressed air treated by an air filter with a filtration degree one level higher than the accuracy of the filter element being tested and a water separation efficiency of not less than 80%. 6.1.2 Ambient temperature
Ambient temperature 5~40℃.
6.1.3 Relative humidity
Relative humidity of surrounding air ≤90%.
6.1.4 Test pressure
The test pressure shall be as specified in Table 3.
Nominal pressure MPa
Pressure resistance
Sealing
Water separation efficiency
Pressure drop-air flow
Drainage device
Allowable fluctuation value of standard pressure
6.1.5 Test instrument accuracy
JB/T7374-94
1.5 times nominal pressure
Nominal pressure
The accuracy of the pressure gauge used for the test is specified to be not less than Class 0.4 for type test and not less than Class 2.5 for factory test. The upper limit of the measuring range shall not be greater than 2 times of the test pressure: the flow meter shall not be less than Class 2.5; the thermometer (meter) shall be ordinary grade. 6.2 Performance test
6.2.1 Sealing test
The test pressure of the air filter shall be as specified in Table 3. The outlet shall be blocked and immersed in water for 15 to 30 cm for 10 seconds. 6.2.2 Pressure resistance test
The test pressure of the air filter shall be as specified in Table 3. The outlet shall be blocked and the pressure shall be maintained for 1 minute before the test. 6.2.3 Filtration degree test
a. The principle of the filtration degree test circuit shall be as shown in Figure 1. Figure 1 Schematic diagram of filtration degree test circuit
1-Air source: 2-Setter: 3-Flowmeter; 4-U-type pressure gauge, 5-Container and test device 6-Filter element to be tested b. Put the filter element to be tested into a container containing ethanol, the liquid level shall cover the filter element, cover and seal it, and extract the remaining air in the filter element. The device is shown in Figure 2.
JB/T7374-94
Figure 2 Filter element evacuation device
1-Motor; 2-Vacuum pump; 3-Sealed container; 4-Filter element to be tested c. Take out the filter element and install it on the test device. Add ethanol, and the liquid level is about 15mm from the upper end of the filter element. d. While the filter element is rotating, adjust the pressure of the set valuer, starting from 0, and adjust the pressure once for each rotation. When the filter element first generates bubbles, start measuring its pressure and flow rate, and continue measuring until the rate of change of the air volume is relatively stable. Draw the measured values into a curve, and make the CD extension line and the intersection point h of the force axis, as shown in Figure 3. PPa
e. Calculate the filtration degree d using the following formula:
d = k × 0. 408 × 10f × r/h(μm)-the surface tension of ethanol is 0.0230, N/m
wherein, r
h-the slope of the curve and the pressure at the intersection point of the ordinate axis, Pat-the empirical coefficient, which is taken as 0.48~0.52.
6.2.4 Water separation efficiency test
6.2.4.1 The principle of the water separation efficiency test circuit is as shown in Figure 4, and the pressure hole structure is as shown in Figure 5. 6.2.4.2 The inlet air pressure supplied to the air filter to be tested is 0.63MPa, the outlet pressure is 0.62MPa, and the water is evenly distributed at the ratio of 30mL of free water per 1m of air. 6.2.4.3 Operation procedure
JB/T7374-94
Figure 4 Schematic diagram of water separation efficiency test circuit
1-air source, 2-air or pressure valve; 3, 6-pressure gauge: 4-water supply device (can be replaced by oil mist device): 5-tested air filter, 7-throttle valve, 8-flow meter Figure 5 Pressure taking hole structure
a. First supply water, after ventilation for 2~3 minutes, discharge the water stored in the tested filter into the net measuring water supply, the water supply amount is more than 1/4 of the effective volume of the water storage cup. Ventilate for 1~2min, and measure the water supply and separation water b respectively.
Water separation efficiency calculation formula:
×100%
Where: \-—water separation efficiency,
Q, -separation water volume.cm;
Qwater supply, cm,
d. Repeat the above procedure 3 times and take the average value. 6.2.5 Pressure drop-air flow test
6.2.5.1 Principle of pressure drop-air flow test circuit According to Figure 6, Figure 6 Principle of pressure drop-air flow test circuit 1-air source; 2-cut-off valve: 3-air decompression valve: 4.6-pressure gauge: 5-tested air filter: 7-throttle valve: 8-flow meter 5
JB/T 7374-94
6.2.5.2 Filter test pressure According to Table 3, adjust the throttle valve opening to gradually increase the flow until the outlet pressure drop reaches 5% of the inlet pressure, measure the air flow, and the inlet pressure remains unchanged during the test. 6.2.6 Drainer performance test
6.2.6.1 Manual drain test
Add clean water to the water storage cup of the air filter (do not add water for factory inspection), close the outlet, and test the pressure as specified in Table 3. Open and close the manual drain for inspection.
6.2.6.2 Automatic drain test
The principle of the test circuit is as specified in Figure 7.
Figure 7 Schematic diagram of the automatic drain test circuit
1 Air source; 2-load check valve; 3-air pressure reducing valve: 4-pressure gauge; 5-water adding device (can be replaced by oil collector>, 6-tested object: 7-throttle b. The test pressure of the air filter is as specified in Table 3. Add clean water through the water adding device, adjust the throttle opening, and gradually increase the water in the water storage cup of the tested object for inspection.
6.3 Appearance quality inspection
Appearance quality inspection is carried out by visual inspection.
7 Inspection rules
7.1 Factory inspection
7.1.1 Each air filter must be inspected and qualified by the factory inspection department before it can be shipped, and a certificate of conformity must be attached.7.1.2 Factory mandatory inspection items5.2.1,5.2.6 ,Article 5.2.7. 7.1.3 Factory inspection items Article 5.2.2,
7.1.4 The number of inspections shall be 2% of the output of each batch (natural batch), but shall not be less than 3 units. 7.1.5 Judgment rules
According to Article 6.1.4 of JB/T6378.
7.2 Type inspection
7.2.1 When any of the following situations occurs, the product shall be subject to type inspection: a.
When new products are trial-produced or old products are transferred to the factory for production; after formal production, if there are major changes in structure, materials, and processes that may affect product performance; during normal production, regular inspections shall be carried out, not less than once every three years; when the product is discontinued for one year and production is resumed; when the factory inspection results are significantly different from the last type inspection: National When the quality supervision agency proposes the requirement for type inspection, the number of pneumatic components for type inspection is stipulated as 3 units (pieces), of which - units (pieces) are subject to full-item tests, and the rest are subject to performance tests only. If there are unqualified items in the test, the tested pieces shall be double-inspected. If there are still unqualified ones, the pneumatic component type inspection is unqualified. 8 Marking, packaging, purchase and storage
8.1 Marking
The outer surface of the air filter shall be marked with:
Product name, model, specifications:
Nominal pressure;
Flow direction:
Filtration degree;
Thread mark of the pipe;
Manufacturer name;
Manufacture date.
Inner packaging
JB/T737494| |tt||Material such as paper box, polyethylene blown film for packaging, mulberry air cushion film, polystyrene foam plastic should be selected. b.
Pack with plastic, pack each component into a bag, and fold the bag mouth. Pack with paper box: pack each 1, 2 or 5 bags into a box. 8.2.2 Outer packaging
The outer packaging of components should be corrugated paper boxes, calcium plastic corrugated paper boxes or nail board boxes. The outer packaging with special requirements shall be agreed upon by the supply and demand parties. 8.3 Purchase and storage
Each air filter should be stored in a warehouse with an air temperature of 5~40℃ and a relative humidity of no more than 80%. The air in the warehouse should not contain corrosive and harmful impurities.
Additional remarks:
This standard is proposed and managed by Wuxi Pneumatic Technology Research Institute of the Ministry of Machinery Industry. This standard is drafted by Shanghai Pneumatic Complete Set Company and Wuxi Pneumatic Technology Research Institute. The main drafters of this standard are Zou Zongfa and Zhang Jiansong.
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