Decision method for testing in-service water turbine runner crackle

Abstract

The invention discloses a decision method for testing in-service water turbine runner crackles, comprising the following steps of: opening a manhole of a draft tube to set up a testing platform, and then testing outlet and inlet edges of a runner blade and the ends of upper and lower ring fillet welds by adopting a penetrant testing method. For testing of the in-service water turbine runner crackles, the decision method tests the outlet and inlet edges of the runner blade and the ends of the upper and lower ring fillet welds, so the false dismissal probability can be greatly reduced in testing, and the testing time can be greatly shortened and the use level of a penetrant check agent is reduced. Penetrant testing (PT) can be screened out from the conventional four testing methods. The testing method can be implemented after a runner is lifted out of a volute and the manhole of the draft tube is opened to set up the platform without disassembling a generator set when testing the in-service water turbine runner, thereby satisfying the economical efficiency of the overhauling work.

Description

technical field [0001] The invention relates to a detection method for a runner of a hydraulic turbine, in particular to a method for judging the crack detection of a runner of a hydraulic turbine in service. Background technique [0002] The runner of the water turbine is an important component of the generator set of the hydropower plant. Its function is to convert water energy into mechanical work to drive the generator to generate electricity. In recent years, with the development of the material field, the material of the turbine runner blade is mostly made of high-strength martensitic steel instead of the original common material. In this way, the amount of steel is reduced, thereby improving the power generation efficiency. On the other hand, the cavitation problem of ordinary materials is also solved due to the increase in strength. However, the use of new materials also brings some negative effects. Because the strength level of blades made of martensitic materials...

AI Technical Summary

Problems solved by technology

In random inspection, since the formation mechanism of the runner crack is not considered, it is easy to cause missed inspection of the crack

However, a full inspection will waste a lot of manpower and material resources, and delay the maintenance time. Taking a single full inspection of a hydraulic turbine runner as an example, the existing inspection uses 30 sets of penetrant flaw detection agents, and the time is 2 days. There is a long maintenance period. Low efficiency, affecting power generation efficiency and other issues

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