Numerical Simulation Of Temperature And Residual Field In P92 Steel Welding Process

Power industry of our station now faces to big challenges, the shortage of power in the economic development becomes more evident. Thermal power industry is the key point of development in China, its electricity generation accounts for more than 80 percent of the total. Using the high temperature and strength steel is the effective way to improve the Thermal Power efficient and it can ensure that equipments perform well at the condition of higher temperature and pressure. This paper is on the base of Ultra-supercritical P92 steel of the power plant. It is calculated and analyzed the P92 steel welding temperature by using physical tests and ANSYS FEM simulation. At the same time it also calculated the residual stress field by using the indirect method of calculating the results of the temperature field.Based on the theory, this paper showed that the corresponding welding temperature curve which is on the use of infrared imaging system on the P92 steel welding process for the temperature measurement, and the result is regarded as the standard to confirm the succeeding temperature field simulation right or not. In summing up the working of predecessors, it represented the welding process of finite element analysis theory systematically, and for the joint-P92 pipe ANSYS finite element model, it completed the analog of metal deposit and mobile sources of heat which is using the birth-death element technology, function and array of ANSYS. By the after treatment, it obtained the corresponding welding temperature curve.Compared to the curves which achieved by the infrared imaging system, they are in good agreement. It means the simulation results of temperature field is correct, and can be used as the basis for calculation of stress field in the following steps. In the theory of heat elasto-plasticity, it calculated the welding residual stress through the conversion from thermal element to structure element using the indirect method. Through the comparison of the results in stress changes between fore and after welding heat treatment, it proved that heat treatment after welding can eliminate the residual stress in some way and it also pointed out the position of stress concentration on the surface of joint.