Do you know the high-temperature mechanical properties of the gasket

Bolt, High strength bolts, Screw

High temperatures typically have adverse effects on the performance of gasket joints. For example, high temperatures can reduce the mechanical properties of gaskets, including tensile strength, rebound rate (elastic modulus), and load-bearing capacity. For example, most rubber bonded asbestos or non asbestos fiber materials (excluding flexible graphite) decompose, pulverize, or permanently deform at high temperatures, and the maximum service pressure decreases with increasing temperature. Secondly, high temperature also significantly enhances the creep or relaxation of the gasket.



For example, under the same load, the asbestos rubber gasket at 200 ℃ reaches 3.5 times the room temperature; The continuous working temperature of flexible graphite gaskets used as substitutes for asbestos in oxidizing media should not exceed 343 ℃. The thermal expansion or contraction of the gasket changes the stress of the gasket, resulting in corresponding changes in its sealing ability. In addition, thermal fluctuations or cycles can lead to joint gasket deformation ratcheting and stress ratcheting effects, which depend on the viscoplasticity of the gasket, nonlinear response to stress-strain, and temperature.