Study On Life Prediction Method Of Nuclear Pressure Vessel And Piping

The nuclear reactor pressure vessels and piping plays an important role in reactor safety and normal operation. Howerver, the main reason of nuclear leakage are the fatigue damage and the corrosion of the nuclear pressure vessels and piping. Based on304steel which is widely used for nuclear pressure vessels and pipelines, the paper researches the fatigue properties of materials and the fatigue life prediction of components.This paper use the total strain control to study the low cycle fatigue test of homebred304stainless steel under room temperature. Using Manson-Coffin equation, Keisler life prediction model for the materials fitting of low cycle fatigue data. By comparing the prediction results, the Manson-Coffin equation fitting accuracy is higher, Keisler model fitting effect is poorer, and forecast the conservative tends to life.By static tensile test obtain the basic mechanical properties of materials such as the basic materials tensile strength, rupture strength and elastic modulus, etc. Through the low cycle fatigue tests got strain-life relationship of under different strain levels. Through the analysis the specimen fracture, observe sample source of crack and fatigue crack propagation, analysis the reason of damage. By metallographic test, to study the microscopic changes in material testing before and after the test, make a further study of fatigue mechanism.Due to the Manson-Coffin equation for Manson-304stainless steel predict assessment is very good, combining with local stress and strain put forward the theoretical model of life prediction. Then based on fracture mechanics, combined with the actual conditions of nuclear key components, to predict the life of component parts.