Sealing refers to the property that can ensure there is no leak under a certain differential caused by internal and external pressure. When the bellows assembly works, there will be filled with gas or liquid medium, and it will be a certain pressure, so, it is necessary to ensure tightness.
vacuum switch in vacuum arc-extinguishing chamber
Vacuum switch is consist of airtight insulation shell, moving-end cover plate, fixed -end cover plate which are made by glass and ceramic and stainless steel corrugated pipe to composite the airtight insulation system. The function of stainless steel corrugated pipe is not only isolate the interior vacuum condition of the vacuum arc-extinguishing chamber from the external state of the atmosphere, but also can make the moving -contact movement with conductive rod within the prescribed scope, to complete the closing and breaking operation of vacuum switch.
Corrugated pipe is a thin wall component made by 0.1 ~ 0.2 mm thickness stainless steel, its fatigue life related to the working conditions of heating temperature, after the vacuum arc-extinguishing chamber divide large short-circuit current, the waste heat of conducting rod will pass to corrugated pipe, and make corrugated pipe temperature increased, the switch life up to 40000 times.