Experimental Investigations on ThermoMechanical Tensioning (TMT), comparison with Heat Sink, and Its Application to a Grillage Structure

Thin plates, which are widely used in ship structures, undergo weld-induced buckling distortions because of their lower critical buckling strength. Thus, there is a need for an active in-process distortion control mechanism in the welding involving thin plates. In this regard, a ThermoMechanical Tensioning (TMT) method was developed and implemented successfully. In the current work, experimental investigation of the effect of TMT pull on the resulting welding distortions is studied and also the TMT process is compared with a heat sinking technique. The experimental results indicate that an increase in the TMT pull would reduce the extent of weld-induced buckling distortions. The results also suggest that a complicated heat sinking technique can be effectively replaced by a TMT process in reducing the welding out-of-plane distortions. The concept of TMT is further extended to the fabrication of grillage structures used in ship structures, which includes longitudinal and transverse welds.