Systematic method for positioning clamps and strongbacks based on their influence on welding displacements

Abstract To control welding displacements, mitigation methods such as clamps and strongbacks are widely used in heavy industries. It can be easily concluded that providing for as many clamps and strongbacks as feasible on welded structures to minimize welding displacements is common knowledge, but this may not always be feasible due to restrictive work environments as well as cost factors and interference from other portions of the structure. Currently there is not a distinct system to efficiently position clamps and strongbacks at welded structures. Based on understanding of how clamps and strongbacks effect on the reduction of welding displacements, a systematic method to efficiently position them will enable improvements to the welding process. In the present study, several cases which have differently positioned clamps and strongbacks at welded structures were numerically simulated by the elastic Finite Element Method (FEM) using inherent strain theory to investigate the influence of clamps and strongbacks on the reduction of welding distortions. According to the simulation data, the applicable systematic method for efficiently positioning clamps and strongbacks for minimizing welding deformations is proposed herein.

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