| High frequency electric resistance weld makes electricity congregated on the surface of interfaces by the skin effect and the proximity effect of high frequency electricity. The temperature of interfaces rises very quickly, and when interfaces are melted or become the condition of plasticity, they are pressed to be a welded joint.As other methods of weld, high frequency electric resistance weld also produces residual stress. Compared with the normal arc-welding, the welding seam of high frequency electric resistance weld are very narrow, so there are new characteristics of the residual stress of the high frequency electric resistance welded pipe. But there is not enough reports of the residual stress of the high frequency electric resistance weld up to now. First, this research measures the mechanical capabilities of the welding seam and the HAZ. Then measures the residual stress of high frequency electric resistant welded pipe using the central-hole method and analyses the residual stress with ANSYS nonlinear finite element program. At last compute the values of residual stress with standard BS7910 and SINTAP.The research measures the mechanics capabilities of the welding seam and the HAZ, including rigidity test, pulling test, impact test, CTOD test. Then measures the residual stress of high frequency electric resistant welded pipe using the central-hole method and analyses the residual stress of the welding seam in the welded process with ANSYS nonlinear finite element program. The experimental results show mostly conformity compared with the simulate results. And the distributing of residual stress of high frequency electric resistant welded pipe compared with the distributing of normal arc-welding, but the numerical values are smaller. This result is important to weld project. But when calculated with BS7910 and SINTAP, we found that the residual stress of high frequency electric resistance weld is smaller, so the formulae of the two standards are not available.
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