This standard specifies the pore size, classification and brand of laboratory sintered (porous) filters based on the measured pore size. This standard applies to laboratory sintered filters made of glass, quartz glass, ceramics, metal and plastic materials. GB/T 11415-1989 Laboratory sintered (porous) filter pore size, classification and brand GB/T11415-1989 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Laboratory sintered (porous) filters
Pore size, classification and designation
Laboratory sintered (fritted) filtersPorosity grading, classification and designation
GB 11415—89
This standard refers to the international standard ISO47931980 for laboratory sintered (porous) filters pore size, classification and designation. 1 Subject content and scope of application
This standard specifies the pore size, classification and designation of laboratory sintered (porous) filters based on the measured pore size. This standard applies to laboratory sintered filters made of glass, quartz glass, ceramics, gold and plastic materials. 2 Reference standards
GB5249 Determination of pore size for permeable sintered metal materials Bubble test GB5250 Determination of fluid permeability of permeable sintered metal materials 3 Terminology
3.1 Sintered (porous) filter: A filter made by heating to bond particles. 3.2 Pore size: The maximum equivalent capillary diameter calculated from the minimum pressure required for the first bubble to escape from the surface of the test sample when the test gas is forced through the sample immersed in the test liquid. 3.3 Permeability, the air flow rate through the filter under specified conditions. 4 Filter classification and brand
Filters should be classified according to the eight pore sizes specified in Table 1. For special requirements, the pore size can be narrower than the range given in Table 1, but the pore size range should be marked.
The brand of the filter is specified by the upper limit of each pore size with the letter "P" in front. Approved by the State Bureau of Technical Supervision on July 4, 1989 202
Implementation on February 1, 1990
Technical requirements
GB11415-89
Filter classification and brand
Aperture classification
5.1 Under normal use conditions, the filter should not have particles falling off, and should be able to withstand a working pressure difference of 1.013×105Pa in the vertical direction. 5.2 Limit of aperture
When the filter is measured by the method specified in the appendix, the aperture should be within the corresponding range specified in Table 1 and as close to the middle value as possible. 5.3 Pore uniformity
If it is required to test the uniformity of the filter on its entire working surface, it should be measured according to the method in Appendix B. 5.4 Permeability
If it is required to test the permeability of the filter, it should be measured according to the method in Appendix C. The permeability should not be less than the provisions in Table 2. Table 2 Permeability of filter
To: The minimum permeability in the table is equivalent to a sintered plate with a thickness of 6 um. cm*/(cm*-min)
Minimum permeability (pressure difference 100Pa)
A1 Principle
GB11415-89
Appendix A
Aperture determination method
(Supplement)
This method is to determine the pressure when the first bubble escapes from the filter plate under specified conditions. This pressure is used to calculate the equivalent capillary diameter. It is not the actual pore size of the material and can only provide the pore size related to the maximum particle size that can pass through the filter. A2 Determination device
The determination device is shown in Figure A1.
Aperture device
1—Test sample; 2—Test liquid; 3—Precision control valve; 4—Air inlet; 5—Pressure A3 Test liquid
A suitable test liquid should be selected during the determination. For coarse filters, water is the best test liquid; for fine filters, liquids with low surface tension should be used. For samples that are not wetted by water or are easily damaged, organic solvents with good wettability and low surface tension should be used. Mercury pressure gauges or water pressure gauges should be used according to the pressure difference. Table A1 gives the test liquids suitable for filters of various materials. 2
A4 Test steps
A4. 1 Sample wetting
Test liquid
Isopropyl alcohol
Trichloroethane
GB 1141589
Surface tension at 20℃
0, 022
Put the sample in the test liquid for a certain time to make the entire pore of the sample filled with liquid. A4.2 Sample loading
Put the sample on the device shown in Figure AI, and then cover the filter plate with a layer of test liquid as thin as possible. A4.3 Determination
After the sample is loaded, slowly ventilate and gradually increase the air pressure until the first bubble escapes from the filter plate surface, and read the pressure value P at this time. A4.4 Calculation
The maximum pore size of the filter plate is calculated by formula A1: 4× 10°y
Wherein, d maximum pore size, m,
y·surface tension, N/m;
P pressure difference, Pa.bZxz.net
Appendix B
Method for determining filter uniformity
(Supplement)
B1 Use the method for determining pore size specified in Appendix A, +(A1)
B2 As described in A4.3, after the first bubble appears, continue to increase the air pressure until the bubbles are evenly distributed on the entire upper surface, and record the pressure reading at this time. The smaller the difference between the pore size and the maximum pore size corresponding to this value, the more uniform it is, and it should not be less than the minimum value in Table 1 of Chapter 4.
Appendix C
Method for determination of air permeability
(Supplement)
c1 Principle
Let clean and dry air pass through the filter plate under a suitable pressure difference, measure the pressure difference and flow rate of the plate, and calculate the permeability of the sample. It is recommended to use a pressure difference of about 980Pa in general to ensure that the air passes through the filter plate under laminar flow conditions. 205
C2 Determination device
The air permeability determination of the filter plate is shown in Figure C1. 7
GB 11415—89
Figure C1 Air permeability determination device
1—Sample; 2—Air inlet; 3—Pressure control valve; 4--Flowmeter: 5—Voltage regulator; 6—Pressure gauge Test and calculation
Place the clean and dry sample on the device shown in Figure C1 and seal it. Allow air to pass through the sample under a certain pressure difference, and measure the pressure difference, flow rate and effective area of ​​the filter plate.
Calculate the permeability by formula C1:
Where; Φ—permeability, cm\/(cm\·min); Q—flow rate, cm/min;
P—pressure difference Pa;
4—effective area of ​​the sample, cm2.
Additional remarks:
This standard is proposed by the Ministry of Light Industry of the People's Republic of China. This standard is under the jurisdiction of Beijing Glass Research Institute, and p× 102
This standard is drafted by Changchun Glass Instrument Factory, Beijing Glass Research Institute, and the Iron and Steel Research Institute of the Ministry of Metallurgy. 286
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