This standard specifies the technical requirements, test methods, inspection rules, and packaging, marking, transportation, and storage methods for rubber seals used in sulfur hexafluoride high-voltage electrical equipment. This standard applies to rubber seals used in sulfur hexafluoride high-voltage electrical equipment and rubber seals used in its ancillary equipment. JB/T 7052-1993 Rubber seals for high-voltage electrical equipment Technical conditions for rubber seals for sulfur hexafluoride electrical equipment JB/T7052-1993 Standard download decompression password: www.bzxz.net

Mechanical Industry Standard of the People's Republic of China
JB/T7052-1993
Rubber seals for high-voltage electrical equipment
Technical conditions for rubber seals for sulfur hexafluoride electrical equipment
Published on September 23, 1993
Ministry of Machinery Industry of the People's Republic of China
Implementation on July 1, 1994
Mechanical Industry Standard of the People's Republic of China
Rubber seals for high-voltage electrical equipment
Technical conditions for rubber seals for sulfur hexafluoride electrical equipment
1 Subject content and scope of application
JB/T7052-1993
This standard specifies the technical requirements, test methods, inspection rules and packaging, marking, transportation and storage methods for rubber seals for sulfur hexafluoride high-voltage electrical equipment.
This standard applies to rubber seals for sulfur hexafluoride high-voltage electrical equipment and rubber seals for its ancillary equipment. 2 Reference standards
GB1682
GB1690
GB3512
GB5721
GB5722
GB5723
GB6034
GB7759
GB7762
GB10708.1
3 Technical requirements
Determination of tensile properties of vulcanized rubber
Test method for Shore A hardness of vulcanized rubber
Test method for brittle temperature of vulcanized rubber
Test method for liquid resistance of vulcanized rubber
Dimension series and tolerances of O-rings for hydraulic and pneumatic use Rubber hot air aging test method
General provisions for marking, packaging and transportation of rubber sealing productsGeneral provisions for storage of rubber sealing products
General provisions for measuring the dimensions of test pieces and products for vulcanized rubber testingDetermination of compression cold resistance coefficient of vulcanized rubber
Determination of permanent deformation of vulcanized rubber under constant deformation compression at room temperature and high temperatureOzone aging test for vulcanized rubberStatic tensile test methodStructural dimension series of lip seal rings for rotating shaftsPart 1: Inner frame lip seal rings for rotating shaftsReciprocating motion rubber seal ringsStructural dimension seriesPart 1: One-way sealRubber seal ring3.1 The working medium of the seal is sulfur hexafluoride gas, water and air, and the working temperature range is -45~+120℃. 3.2 The seal materials are divided into two groups: Group A (EPDM rubber) and Group B (chloroprene or nitrile rubber). The working temperature range of Group A is -45~+120C, and the working temperature range of Group B is -25~+120℃. 3.30 type rubber seal ring size and tolerance adopt GB3452.1 size series and tolerance; rotating shaft lip seal ring structure size series adopt GB9877.1; reciprocating motion rubber seal ring structure size series adopt GB10708.1; other structural forms and special requirements of seal size and tolerance shall be determined by negotiation between the supply and demand parties. 3.4 Material physical performance indicators shall comply with the provisions of Table 1 and Table 2. Special requirements can be determined by negotiation between the supply and demand parties. Table 1 Group A vulcanized rubber physical properties
Approved by the Ministry of Machinery Industry on September 23, 1993
Implemented on July 1, 1994
Breaking strength
Breaking elongation
Compression cold resistance coefficient
Compression 20%
Hot air aging
(120℃×24h) | |tt||Hardness change
Tear strength change
Tear elongation change
Brittle temperature
Compression set
(120℃×22h）
Ozone aging temperature 40℃
JB/T7052—1993
(Shore A type)
-45℃
Not higher than
Compression 25%
Stretching 50%||t t||Ozone concentration volume fraction 1×10 (10ppm) Vacuum resistant silicone grease (7501) test
(120℃×24h)
Tear strength
Tear elongation
Compression cold resistance coefficient
Compression 20% (-25℃)
Volume changewww.bzxz.net
Table 2 Physical properties of vulcanized rubber of group B
Hot air aging
(120℃×24h)
Hardness Change
Change in breaking strength
Change in breaking elongation
Brittle temperature
Compression permanent set
(120℃×22h）
Ozone aging resistance
Temperature 40℃
Ozone concentration volume fraction 0.5×10-* (0.5ppm) Resistance to No. 25 transformer test
(120C×24h）
The appearance quality inspection requirements of O-rings are listed in Table 3. Energy
(Shore A type)
Not higher than
Compression 25%
Stretching 20%
Volume change
Energy index
No cracking for 10h
Energy index
No cracking for 5h
Defect name
Non-working surface
Convex and concave defects
Convex extension
Mold misalignment
Note: No defects are allowed on the working surface. JB/T7052-1993
Schematic diagram
O-ring cross-sectional diameter
Maximum allowable limit value
Not greater than cross-sectional tolerance
No visible mold processing marks (equivalent to the surface roughness of the cavity not less than
), no frost and mildew
Non-working surface convex and concave defects Under the limit conditions specified in this table, no more than 3 defects are allowed. 3.6 Other structural seal appearance quality inspection requirements refer to Table 3. 4 Test method
4.1 Product appearance
Use visual inspection, and use a projector or tool microscope for identification when necessary. 4.2 Product size
Measured according to GB5723.
4.2.1 Measure the product diameter. The measuring tool can be a tool microscope, projector and other equipment. It can also be measured with special measuring tools such as measuring cone rods, flexible rulers, calipers, etc. whose measurement accuracy is higher than the product size accuracy requirements. 4.2.2 When measuring the diameter of a product with a tool microscope, projector, or caliper, each dimension to be measured requires the measurement of 3 or multiples of 3 evenly distributed measurement values ​​and the arithmetic mean value.
4.2.3 The product cannot be deformed or moved directly during measurement. 4.2.4 When measuring the cross-sectional dimensions of a product, the measuring tools can be a tool microscope, projector, micrometer, caliper, or other instrument or tool, or a shape measuring instrument. It can also be measured using the destructive slice projection measurement method. 4.2.5 The cross-sectional dimensions of the 0-type sealing ring product must measure the axial cross-sectional dimensions and radial cross-sectional dimensions separately. 4.3 Material physical property test
4.3.1 The preparation of the sample shall be measured in accordance with GB5723. 4.3.2
Hardness (Shore A type) shall be measured in accordance with GB531. 3
JB/T7052—1993
Tear strength and elongation at break shall be measured in accordance with GB528 using a dumbbell-shaped specimen of type 1. Brittle temperature shall be measured in accordance with GB1682.
Liquid resistance test shall be measured in accordance with GB1690. Aging resistance test shall be measured in accordance with GB3512. Compression cold resistance coefficient shall be measured in accordance with GB6034. Compression permanent deformation shall be measured in accordance with GB7759. Ozone aging resistance shall be measured in accordance with GB7762. 5 Inspection rules
5.1 The manufacturer shall inspect the sealing materials according to the items specified in Table 1 and Table 2 of this standard. If the materials fail to meet the standards, they shall not be put into production. Items 1, 2, 3, 5, and 7 in Table 1 and Table 2 are routine inspection items, which are required to be inspected batch by batch (i.e., each mixing unit). Items 4, 6, and 9 in Table 1 and Table 2 are required to be inspected at least once a quarter, and Item 8 in Table 1 and Table 2 are required to be inspected at least once a year. 5.2 When one of the following situations occurs, all inspection items specified in this standard shall be inspected. a. During the finalization and trial production of new products; b. After formal production, if there are major changes in materials, structures, and processes that may affect product performance; c. During normal production, after a certain amount of production is accumulated regularly, an inspection shall be carried out periodically; d. When production is resumed after a long period of suspension; e. When the national quality supervision department makes a request. 6
Packaging, marking, transportation, storage
Packaging, marking, and transportation shall comply with the provisions of GB5721. The manufacturer shall mark the material characteristics with color dots that are not damaged and do not affect the use of the product in a conspicuous position on the non-working surface of the seal. 6.1
a. EPDM rubber uses white dots;
b. Nitrile rubber uses blue dots;
c. Neoprene rubber uses yellow dots.
6.2 Storage should comply with the provisions of GB5722.
6.3 The manufacturer must attach a certificate of conformity to each package of the seals shipped out of the factory, and the certificate of conformity must indicate the product specifications, quantity, date of shipment, and the inspector's seal.
Additional Notes:
This standard was proposed and managed by the Guangzhou Machine Tool Research Institute of the Ministry of Machinery Industry. This standard was drafted by Xingping Sealing Components Factory. The main drafters of this standard are Kong Wen, Hou Hui'e, Wang Wenlong, Yuan Fangxia, and Wang Jianrong. 4
People's Republic of China
Mechanical Industry Standard
Rubber seals for high voltage electrical equipment
Technical provisions for rubber seals for sulfur hexafluoride electrical equipment
JB/T7052-1993
Published and issued by the Mechanical Science Research Institute
Printed by the Mechanical Science Research Institute
(No. 2 Shouti South Road, Beijing
Postal Code 100044)
Book size 880×12301/16
Sheet 1/2
Word count 8000
First edition in May 1994
First printing in May 1994
Print run 1-500
Price 3.00 yuan
Mechanical Industry Standard Service Network: http://www.JB.ac.cn66_
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