Analysis method of local thinning of valve body

Abstract

The invention provides a valve local thinning analysis method. The method mainly comprises the steps of 1) completing representations of local thinning defects of a valve to be analyzed; 2) creating a valve CAD model; 3) building a local thinning defect model which is saved in formulas supported by finite element software in the valve CAD model; created in the step 2) according to long radius and short radius of the spheroid obtained in the step 1) and the proportion of the local thinning defects accounting for the spheroid; 4) importing the model completed in the step 3) into use finite element analysis software; 5) endowing the model material attributes according to materials of the valve to be analyzed; 6) building a finite element analytical model; 7) calculating the finite element analytical model completed in the step 6) in the finite element software, processing results after processing, and extracting stress parameters required by subsequent valve local thinning analysis and evaluation. By the aid of the method, all stress parameters required by subsequent valve local thinning analysis and evaluation can be obtained, and effective analysis is achieved.

Description

technical field [0001] The invention relates to a finite element analysis method, in particular to an analysis method for local thinning of a valve body. Background technique [0002] During the operation of the valve, due to the scouring and mass transfer of the large turbulent flow, erosion or flow-accelerated corrosion may occur in the sensitive parts of the complex structure of the valve body, and local thinning may occur. Since the 1980s, serious valve body thinning has been found in nuclear power plants, such as the erosion of the valve body of the 16-inch globe valve in the US nuclear power plant and the accelerated corrosion of the valve body in the 16-inch main feedwater isolation valve of the South Korean nuclear power plant. , which affect the safe operation of nuclear power plants. Once the valve body leaks or ruptures due to local thinning and failure, it will cause high-temperature and high-pressure medium to leak out, which will not only affect the operation ...

AI Technical Summary

Problems solved by technology

Since the structure of the valve body is much more complicated than that of ordinary pipe fittings, and the reasons, locations and distribution rules of local thinning are also complicated, and large-diameter valves have thicker valve body wall thickness, so the modeling and numerical analysis of general pipelines and containers The method is not applicable to the valve body, and there is no public modeling and numerical analysis method for valve body thinning

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