Research On Submersible Pumps Reliability Enhancement Testing And Statistical Analysis

In this dissertation, the model QDX-1.5-32-0.75 submersible pump was taken as the object, a systemic and deep research on the submersible pump's failure detecting system, Reliability Enhancement Testing (RET) method and data statistical analysis were done.Firstly, introduced the significance of reliability research, briefly stated the developing history and current situation of Reliability Engineering domestic and abroad. Then, reliability test methods and data analysis methods were introduced. Also, the existing problems of above were mentioned, the current research on submersible pump's reliability and existing problems were presented.Secondly, did an FMECA (Failure Mode Effect and Criticality Analysis) to submersible pump and found out that the mechanical seal and the bearing are the weakness parts of the whole submersible pump. Confirmed that leakage is mechanical seal's failure character and enhanced vibration is bearing's failure character. According to the classical working environments, did analyses of the two parts' failure mechanism. The two weakness parts' failure characters and failure mechanisms are the base of further failure detecting and reliability testing.Thirdly, established the method of detecting the failure of submersible pump according to mechanical seal and bearing's failure characters, at the same time, other kinds of submersible pump's failure were also taken into consideration. Detected mechanical seal's failure by oil-water sensor, detected bearing's failure by vibration sensor and detected the whole submersible pump' running situation by electricity. Then, introduced the research and development of the submersible pump' reliability test system, presented an appropriate failure criterion of submersible pump. A real detecting case versified the effectiveness of the reliability test method.Fourthly, according to the principle of RET and the failure mechanism of weakness parts, water with 10% emery was chose as enhancement stress, submersible pump's reliability enhancement test method was studied and a test project of RET was presented. Five QDX-1.5-32-0.75 pumps were input into RET, and four of them were failed. The results of the RET showed that water with 10% emery was appropriate enhancement stress.Fifthly, chose exponential distribution to describe submersible pump's life distribution approximately and chose failure rate A as the reliability characteristic parameter. Because of a few failure data in the test, so Bayes method was introduced...