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A new moving or dynamic thermal tensioning technique-welding with trailing intense cooling was numerically simulated by finite element method(FEM)and experimentally investigated.The simulation results indicate that trailing intense cooling can increase significantly the longitudinal tensile plastic strain within the weld and its adjacent zone during cooling stage,which can partially or completely counterbalance the longitudinal compressive plastic strain formed in the heating stage and the solidification shrinkage formed in the cooling stage.Therefore the longitudinal shrinkage remaining in the weld and the adjacent zone is greatly reduced,which means that the residual stresses in the weldments are kept in a lower value and the residual distortion can be mitigated effectively.Meanwhile a series of parametric studies were conducted to demonstrate the influences of several key parameters such as cooling distance, cooling power and cooling width on the effectiveness of distortion control.Experimental results also verify the effectiveness of this distortion control technique and the reliability of the numerical simulation.