There are significant differences between non-metallic expansion joints and metallic expansion joints in a number of respects.
First of all, from the material point of view, the metal expansion joint is mainly made of stainless steel, carbon steel, copper, aluminum and other metal materials, which give the metal expansion joint good working performance in high temperature and high pressure environment. Non-metallic expansion joints are mainly made of rubber, polyurethane, polytetrafluoroethylene and other highly elastic materials, which make them unique in some specific industrial fields, such as food, medicine, semiconductor, etc.
Secondly, from the perspective of the pressure and temperature range, metal expansion joints are generally suitable for high-temperature and high-pressure media due to the characteristics of metal materials, and can withstand higher pressure and temperature. However, the non-metallic expansion joint has a relatively small pressure and temperature range, so it is usually suitable for some low pressure and low temperature environments.
Furthermore, from the perspective of the installation method, metal expansion joints usually need to be fixed by welding or bolting, which may require more time and expertise during the installation process. The non-metallic expansion joint can be installed by flange connection or clamp connection, which is more convenient and suitable for occasions where quick installation and disassembly are needed.
Furthermore, non-metallic expansion joints are generally lighter and smaller than metallic expansion joints in weight and volume, which gives it an advantage in some space-constrained situations. At the same time, the non-metallic expansion joint also has the characteristics of convenient installation and disassembly, quick connection, fireproof, high explosion-proof and pressure-resistant, good sealing performance, etc., and has a long service life. Even if the sealing surface is damaged, it can be used continuously only by replacing the sensitive parts.
In general, non-metallic expansion joints and metal expansion joints each have their own characteristics and advantages, and which expansion joint to choose mainly depends on the specific application scenarios and needs. In practical application, the type of expansion joint should be reasonably selected according to the factors such as temperature, pressure, medium characteristics and convenience of installation and maintenance of the working environment.