Metal bellows has the characteristics of being able to produce corresponding displacement under the effect of pressure, axial force, transverse force or bending torque. It also has the performance of pressure-resistance, vacuum sealing, corrosion-resistance, temperature stability and long service life. Therefore, it has been widely used in many industrial fields.
In various bellows valves, whether it is sanitary shut-off valve, throttle valve, regulating valve or pressure relief valve, the bellows is always used as the filler-free sealing isolation component of the valve. During the operation of the valve, the bellows is axially displaced and reset together with the valve stem. At the same time, it also sustains the pressure of the fluid and ensures sealing. Compared with the filler sealing valve, bellows valve has higher reliability and longer service life. Therefore, bellows valve has been widely used in industrial fields such as nuclear industry, petroleum, chemical, pharmaceutical and aerospace.
In practical applications, bellows is often welded together with other components such as flange, pipe and valve stem to form bellows component. Welding becomes an indispensable process in the production of bellows components. With the development of scientific research and production, there are new requirements for the welding tooling and equipment of bellows. According to these requirements, new type of bellows welding equipment needs to be developed.