Abstract：The steam generator in the nuclear power plant of lead or sodium-cooled fast reactor is used for heat exchange between liquid metal and water. The heat exchange part of the steam generator is composed of heat exchange tubes arranged in a row. Bonded double-wall pipe is a kind of pipe with high heat transfer efficiency and resistance to crack propagation. Residual pressure exists between the inner and outer tubes of this kind of tubee, which is a sign that the inner and outer tubes are pressed together. However, after rising to high temperature and then getting cooled, the residual pressure between the inner and outer tubes may disappear and cause detachment. Temperature in order to know the specific influence of joint type double-wall tube, this paper designs a stretch of the double-wall pipe, and at the same time, the finite element numerical simulation method, the simulation of the pipe processing preparation and residual stress between the inner and outer pipe is obtained, and then simulated the process of cooling down after heating, analyzed the change of residual stress and strain state of the heat exchanger tube, and verified by preliminary tests. Through the study, the results show that the plastic deformation caused by the temperature change is the main reason for the change of residual stress between the tubes. The method of controlling the degree of tube processing by controlling the tube processing is expected to cope with the effect of temperature variation on tube stability.
2022, Vol. 43 
