Electric arc-welding steel plates using support straps - minute gap between strap and plate permits escape of gas during welding

摘要

In the welding of joints where the bead can only be laid from one side, a support or cover-strap is fixed to one of the plates before making the joint. Normally, the strap is welded in posn. and there is no chamber for air or gas to escape. The novelty is that a gap is left between the strap and plate for the escape of gases, thus avoiding porosity in the main joint. This process is suitable welding e.g. box girders where a rectangular strap is fixed to the plate, the web resting against the strap. Before welding the strap to the plate, thin shims are inserted (and removed after welding) so that a path is provided for gases to escape when the web is welded.