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The difference between asbestos and non-asbestos sealing materials

Under the pressure of strict environmental protection investigations, all walks of life are undergoing rectification. In the valve industry we produce, asbestos and non-asbestos are also a factor influencing environmental protection, so let's analyze the difference between the two:

1. Asbestos sealing materials are more resistant to high temperatures than non-asbestos sealing materials. The main components of asbestos sealing materials are asbestos, fillers and rubber. The asbestos and fillers have high temperature resistance; the main components of most asbestos-free sealing materials are mineral fibers, organic fibers, fillers and rubber, of which organic fibers are generally resistant to temperature. At about 200 °C, the current maximum temperature resistance of asbestos gaskets has reached about 1000 °C.

2. Asbestos sealing material has higher mechanical strength than non-asbestos sealing material.
(1) The surface of the asbestos fiber is accompanied by a polyvalent metal cation, which is easy to form a strong interface with the rubber having a negative charge on the surface, thereby improving the bonding strength of the rubber fiber, that is, improving the mechanical strength of the asbestos sealing material. However, the direct affinity of various non-asbestos mineral fibers and rubber substrates is not as good as that of asbestos, so the bonding strength of rubber fibers is not as good as that of asbestos.
(2) Asbestos fibers can be subdivided almost infinitely, and their specific surface area is larger than that of non-asbestos mineral fibers, so the reinforcing effect is obvious.
(3) The tensile strength of asbestos fibers is higher than that of non-asbestos fibers, so the reinforcing effect of asbestos fibers is obvious.

3. Non-asbestos sealing material has better compactness than asbestos sealing material. Because the asbestos sealing material has a high filler content and a different particle size, it can sufficiently fill the micro-gap of the rubber fiber. In addition, asbestos-free fibers do not have a tubular structure like asbestos fibers, but a solid structure, so the compactness is good.

4. As we all know, the seriousness of asbestos materials on human health has long been banned from using asbestos materials in developed countries such as Europe, America and Japan, and China will gradually eliminate asbestos sealing materials, which will be replaced by non-asbestos sealing materials.

5, non-asbestos sealing materials are environmentally friendly, asbestos sealing materials are non-environmental. Asbestos fibers contained in asbestos sealing materials tend to cause silicosis in humans, while asbestos-free sealing materials do not contain asbestos fibers.

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