Simulation And Experimental Study On Creep Characteristics Of P91 Steel Tube Under High Temperature

This paper first introduces the history of high temperature creep analysis and its importance in current social industrial production and environmental protection.Then,the mathematical model of the current high temperature creep analysis method and the finite element analysis software ABAQUS are briefly introduced.Then,according to the test data and theoretical basis,the model of P91 steel material used in the test was built.The high temperature creep characteristics of P91 steel material under various representative stresses at 580? and 620? were simulated and analyzed.The creep strain curve obtained by the k-r model was basically the same as the actual situation,and the accuracy of the simulation was verified.Then,to conforms to the factory production of thick wall cylinder and the concentric reducer creep damage behavior analysis,got them creep process in two stages: stage of elastic and creep stage of the stress and strain images,pipe parts are analyzed in the process of creep stress damage characteristics,determine the risk they creep failure location,for according to the working condition of the pipeline for the factory gives reference to the selection and protection.Based on the modified K-R creep constitutive equation,through calculation,the experiment with various material parameters of P91 steel,and high temperature of boiler main steam pipeline model,service conditions on the simulation analysis was carried out,won the 150000 hours of service pipe creep stress and damage distribution,predict the maximum damage in 2 pipe in the pipe bend,the service life of the pipeline is about 43% of the whole service life,this is consistent with the design life of the pipeline.In addition,the creep stress and damage distribution of t-shaped head with internal compression were further studied.The creep failure time of the t-head was predicted to be about 150,000 hours,and the node where the maximum creep occurred was found: on the outer surface of the cross region of the t-head,which was consistent with the maximum stress in the initial service.