System Of Surfacing Temperature And Residual Stress On High Strength And Corrosion Resistant Alloy Composite Pipe

The rapid development of the national economy makes drilling platform and oil pipeline industry develop rapidly.While internal corrosion is the main form of pipeline damage.The general corrosion resistant method is welding monolayer or multilayer of nickel-based alloys on the internal surface of pipeline.X65 steel and Incoloy 825 welding wire are widely used in oil pipeline.Finite element analysis is an indispensable technical means to predicting residual stress and deformation.In the numerical simulation of residual stress and deformation of the finite element,the number of large structure units and the highly nonlinearity which make the calculation of the geometric multiple increased.It is difficult to accomplish numerical simulation.It is reasonable technology to apply effective mathematical modeling algorithm to predict the optimum technological parameters which based on the simulation calculation.In the process of the calculation,the error back propagation network model of the 3-8-3 structure is set up with welding current,hot wire current and welding speed as input and welding temperature field,residual stress and deformation as output.To analysis the relationship between the welding current,hot wire current,welding speed and the welding temperature field,residual stress,deformation,establish the four dimensional function image of welding process parameters ~ temperature field,process parameter ~ residual stress and process parameters ~ deformation.In the four dimensional function image when the welding parameter is: 190 ~ 200 A(welding current),40 ~ 50 A(hot wire welding),240 ~ 300 mm/min(welding speed),no matter how the three parameters to match,which can meet the requirement.Surfacing is conducted under the optimum process parameters.The X ray diffraction method is carried out to measure the residual stress and the 3D scanning system is carried out to measure the deformation.There are some differences between the measured values and simulated values but the trend are basically similar which can verify the accuracy of the model.When carrying out new analysis by ANSYS,the programs need to be modified or reworked if the working conditions changed.A system of surfacing residual stress and deformation,based on the APDL language and VC platform,is built by the secondary development of ANSYS.The system encapsulated five different kinds of welding form like straight pipe,flange and so on.Through intuitive interface operation,temperature field simulation and stress field simulation of many different kinds of surfacing forms are accomplished.