The Stress Calculation And Assess Of The Microstructure And Capabilities For The 12Cr1MoV Steel's Siphon Of Connecting Pipe

During the long-term operation under high temperature and high-pressure the Connecting Pipe will occurring structure damage and creep damage .Along with the increasing of the damage level of the pipes ,the rupture tenacity and intension of the material will descend gradually.It will increase the possibility of the severe destroy which occur in the connecting pipes especially in it of the extended serving suits .The invalidation of power plant.Thus it will be the key for preventing the early invalidation of the connecting pipes and using fully the residual life of the extended suits on the basis of operation in security to diagnose exactly the damage level and evaluate logically the life of it.This paper deals with the estimate of structure states and capabilities for 151609 hours service exposed connecting pipes. The estimate was made using the analyses of chemical component, normal temperature dynamics , mutually and electric lens, the observe of creep deformations and permanence intension examination. The results indicate: after 151609 hours serviced, the changes such as carbide of microstructure occurred to full degree at the siphon of connecting pipe Creep damage has reached 3 degree and the permanence intension of high temperature declines clearly . When continuing using the connecting pipe, we must supervise it strictly for the security of power plant.