Analysis of the factors involved in failure of a brass sleeve mounted on an electro-valve

Several electro-valves have failed because of the fracture occurred on the internal sleeve made in a typical free cutting leaded brass CW614 N (UNS 36000). The morphology of the observed fracture surface clearly indicates that the failure phenomenon has been ruled by a stress corrosion cracking mechanism. On the other hand, all the electro-valves operate in an environment featured by potable water that does not justify an alchaline concentration...