The pipe between heat exchanger and centrifugal pump under high-temperature and high-pressure.Due to insufficient pipe flexibility,the calculated loads at the nozzle of both the centrifugal pump and heat exchanger exceed the limit value under the design conditions.In order to ensure the safe operation of the pipe and equipment,and considering the site environment,two schemes of natural compensation and set flexible compensator are adopted.Through pipe stress analysis,the optimization effect of the two schemes was evaluated.Finally,the scheme of setting double-tied expansion joint on the standpipe was selected to meet the requirements of pipe stress and the nozzle loads limit for the equipment.