Analysis of Canned-Motor Pump Jamming Failure in Start Hot Standby Mode

The reason of a canned-motor pump start failure is deduced in this paper. It is shown that the undersized gap of the lower guide bearing causes the start failure. By the stripping inspection data, the design value of the guide bearing gap, the cumulative departure of manufacturing assembly and the preloading of the bearing liner lead to the undersized gap. The test result shows that the improved canned-motor pump can start up successfully.