Investigation of the E ect of Clamping on Residual Stresses and Distortions in Butt-Welded Plates


Department of Mechanical Engineering,Iran University of Science and Technology


One major disadvantage of many arc welding processes is welding-induced residual stresses
and distortions. The non-uniform heating and cooling during arc welding result in non-uniform expansion
and contraction of the weld and surrounding base material, which produces undesirable residual stresses
and deformations in the welded joint. A number of methods can be used to control welding-induced
distortions. The methods used for controlling welding distortions a ect residual stresses and vice versa.
One practical method for minimizing welding angular distortions is the use of clamping. In this paper, the
e ect of clamping and clamp releasing time on welding residual stresses and distortions in the single-pass
butt welding of 304 stainless steel plates are investigated. Cases with and without clamping have been
studied, and residual stresses and angular distortions have been predicted by three-dimensional nite
element simulation. Moreover, experiments have been carried out to measure temperature histories,
angular distortions and residual stresses for the unclamped case to verify the numerical model. The results
of this study revealed that clamping and clamp release time have a great in
uence on the distribution of
residual stresses and nal angular distortions. Using clamping during welding and releasing after cooling
to ambient temperature can signi cantly reduce the amount of nal angular distortions.