High repulsive force value between contact members arising mostly at contact closure and / or in transient under short circuit conditions is a real hazard for power contact switch .

真空断路 器在动静触头闭合或电路短路的 瞬时，接触单元之间经常产生很大的排斥力，对电力接触开关的 危害 极大。

However transient flow in pipe network system will be caused when large users start to run or to close . The hazard made by transient flow can result in intensive breakage of pipeline .

然而， 某些大用户开启或关闭都将导致管网系统中产生 瞬变流 现象，由瞬变流动而产生的水 击压力 波可能导致管段的强度破坏。