Structural Strength Analysis Of Heat Exchanger Tube Plate In Medium Operation

The dielectric start-up heat exchanger is an important equipment in the chemical reaction unit to provide heat source for the process medium put into the reactor during start-up so as to ensure that the process medium reaches the temperature of chemical reaction.The tube plate of the heat exchanger and the connection part between the tube and shell side are the key structure of the heat exchanger.The safety and reliability of its design is an important guarantee for the safe and reliable operation of the equipment.At the same time,the design of this part needs to consider the economy and be convenient for processing and manufacturing.In this paper,the heat exchanger of catalytic cracking reactor is taken as the research object,the stress of the tube plate is calculated and the structural strength is studied.The parts of the finite element model is set up and carry on analysis and calculation,the coupled thermo-mechanical analysis method,according to the structure of the eight kinds of dangerous working conditions that may occur in the operation of the temperature field and stress field of the structure calculation,and according to the analysis design standard JB4732,classifying different causes of stress,the structure stress analysis,to verify that the conventional design meets the requirement.On the basis of the finite element simulation results,the hydraulic experiment and operating condition experiment were carried out for the designed and manufactured equipment,and the results of the finite element model analysis and calculation were verified.The results of simulation and field experiments show that the radial stress and the shell flange stress of the heat exchanger and its connection part with the shell side barrel are larger than the allowable stress,which do not meet the design requirements.According to the analysis and design method,the stress of the result is classified and evaluated under the combined working condition,and the maximum ratio of the calculated value of the finite element analysis to the stress strength limit of the tube plate and shell side barrel is 72.08%and 39.2%respectively,which meets the national analysis and design standards.Based on the analysis and design conclusion,the hydraulic pressure experiment and operating condition experiment were carried out on the designed,manufactured and put into use equipment.The experimental results showed that the design and manufacturing of tube-plate and its connection part with shell side and barrel met the requirements of field use,and the correctness of the finite element simulation results was verified.