Backing vs Retainer in Welding

The backing is defined as material placed at the root of a weld joint for the purpose of supporting molten weld metal. Its function is to facilitate complete joint penetration. Permanent backing is usually made from a base metal similar to that being welded and, as the name implies, becomes a permanent part of the joint because it is fused to the root of the weld and is not easy to remove — See: Backing in welding for more information. Temporary backing may be made from copper or a ceramic substance that do not become fused to the root and are easily … Continue reading Backing vs Retainer in Welding

Backing in welding

A backing (strip) is a piece of metal that is placed on the backside of a weld joint to prevent the molten metal from dripping through the open root (burn through). It helps to ensure that 100% of the base metal’s thickness is fused by the weld (full penetration). The backing may be either left on the finished (cofferdam or void space closing welds without both-sides accessibility) weld or removed following welding (Ceramic backing, Copper strips). If the backing is to be removed, the letter R is placed in the backing symbol.  The backing is often removed from a finished weld … Continue reading Backing in welding