This paper presents life test data of two controlled pump assemblies continuously running since September 1993. The tests, running on FLUOROCARBON CCIF2 - CCIF2, are still in progress (Current date May 1997).
One pump operates at the design point, the other one at 3 different RPM's.
Reliability considerations lead to a novel, sensorless, brushless DC motor of very high reliability. Given is an outline of the extensive environmental test compaign and Micro-G tests, with results.
Pump performance data taken prior and after the environmental tests, performances after 1 and 3 years of continuous operation are given and compared. Up to now, after 3 years of operation no pump degradation can be detected.
A pre-runner of the above pumps, featuring the same bearing design is continuously running since November 1990 with no observable degradation.