Technical Analysis On Inspection And Adjustment Of Main Pipe And Hanger Based On 320MW Unit In Zhang Jiakou Power Plant

With the gradual improvement of China's power system,the corresponding requirements for the safety and reliability of power plants have been improved,and it is necessary to carry out the predictive failure analysis of major equipment in power plants.Steam pipe in power plant is a key component of the power plant,operating in harsh conditions of high temperature and high pressure long,prone to metal aging and life decline,often accidents will happen here,so the power plant steam water piping and associated parts hanger failure analysis is particularly urgent and important.The function of supporting and hanger of steam water pipe in power plant is to bear the gravity of pipe,bear accidental impact load and control the displacement and vibration of pipeline under working condition.With the cumulative operation time of the unit,the state of the pipe support hanger will change.The displacement and stress distribution of the pipe will deviate from the design state,so the service life of the pipe will be shortened.Because of the change of the pipe constraint conditions,the phenomenon of the pipe vibration will appear more frequently,and the endpoint of the pipe will also increase the thrust of the equipment,which will endanger the safe operation of the unit.Therefore,regular inspection and adjustment of steam water pipes and other supports and hangers is of great significance for safe and stable operation of the unit.This paper analyzes the common problems in the main pipes and hangers of 320 MW units in Zhangjiakou power plant.The thermal and cold state of the units are checked,and the problems appearing in the inspection are summarized and analyzed.The thermal displacement of the four large pipe support hangers is measured,and the stress calculation of the four pipes is calculated by using the software of the Pipepak,and the calculation is made.The results are compared with the test results.According to the results of calculation and test,the adjustment scheme of pipe and support hanger is given.After transformation and adjustment,the problems of the supporting hanger and transfer to the normal state,the problem of the defect of the pipe support hanger has been basically eliminated.