Canned motor pump or pump with an encased magnetic coupling

摘要

A canned motor pump wherein the can has at least two coaxial tubular walls defining an annular space for the flow of a preferably gaseous fluid which is used to facilitate detection of leaks in the walls of the can. Each tubular wall can individually seal the driving unit from the driven unit of the pump motor. The leak detector can generate visible, audible and/or otherwise detectable signals, and such signals can also serve to stop the motor in the event of leakage.