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March 21, 2018 2018
Materials for Auto Rubber Seasl: EPDM

EPDM sealing strips can be divided into two kinds according to the material: dense strip and foamed bar. 

The hardness of the dense sealing strip is generally between 65 degrees and 90 degrees. The hardness of the foam sealing strip is between 15 degrees and 35 degrees, the product is soft and resilient, and it is suitable for various sealing blocks, sealing gaskets and so on.

EPDM sealing strip can be divided according to the vulcanization method.

(1) Discontinuous sulfuration method (after cutting the extruded strips according to a certain length, then sulfurizing them into the vulcanizing tank, and extruding the semi-finished products of rubber strips into the mold to vulcanized).

2) Continuous vulcanization (microwave continuous vulcanization, salt bath continuous vulcanization, hot air continuous vulcanization, etc.). 

A. Microwave continuous vulcanization compound seal: microwave vulcanization technology is the production technology which was widely popularized after the foreign energy crisis in 1970s. With the continuous microwave vulcanization technology can not only produced by the metal core, dense glue and a variety of materials and foam extrusion, in saving energy, improving work efficiency compared with other continuous vulcanization device is superior. This technology is recognized by the world as the best process for producing extruded products. The characteristic of microwave heating is that heat is generated directly inside the heated object, instead of being imported from the outside as usual, so that it not only generates heat quickly, but also distributes evenly, which is conducive to improving product quality and shortening the heating time. 

B. Salt bath continuous vulcanization seal: salt bath sulfuration with nitrite containing salt bath system, the environmental pollution is larger, has been gradually eliminated. 

C. Hot air vulcanized sealing strip: hot air vulcanization has been developed to strong air vulcanization, that is, high temperature and high speed hot air vulcanization (Tmax:450 degree C and Vmax:60m/s) can also achieve the role of flame pretreatment, and the safety is greatly improved.