The life of the vacuum interrupter mainly depends on the life of the stainless steel bellows of the interrupter. Generally speaking, when the mechanical life of the arc-extinguishing chamber of the vacuum circuit breaker ends, the stainless steel bellows of the arc-extinguishing chamber is broken. At this time, the arc-extinguishing chamber (vacuum tube) is in an atmospheric state, and the movable contact can freely shake due to the loss of atmospheric pressure, and the shielding cover etc. may also change color due to the action of water vapor in the atmosphere. In addition to the quality of the arc extinguishing chamber (vacuum tube) of the vacuum circuit breaker, the mechanical life of the arc extinguishing chamber (vacuum tube) of the vacuum circuit breaker is determined by the quality of the arc extinguishing chamber (vacuum tube) itself. The existence of the following factors may lead to the reduction of the mechanical life.

a. There is acid and other chemical corrosive gas pollution in the storage and use environment of the vacuum interrupter (vacuum tube), and the working conditions are heated and the temperature is too high;

b. The vacuum circuit breaker deforms the stainless steel bellows due to improper use or adjustment;

c. When the vacuum circuit breaker is working, the moving contact travel is too large, or the bounce time is too long, and the bounce is serious;

d. The installation of the guide device does not meet the requirements, causing the moving contact to swing during the movement, and even the bellows to rub;

e. The bellows is subjected to excessive torque, especially when assembling the arc-extinguishing chamber (vacuum tube) moving contact and the tie rod, the force is too large

If the vacuum circuit breaker reaches the mechanical life index of the arc extinguishing chamber (vacuum tube) in actual use, it should be replaced. However, if it is to be used continuously, in order to ensure safety, the inspection period should be shortened according to the frequency of operation. If the performance of the vacuum circuit breaker decreases, it should be replaced immediately.