Steel Solutions Center

8.5. Repairs

8.5.1. Is it necessary to remove tack and erection aid welds that are not incorporated into the permanent welds?

In many cases, welds for temporary fitting aids can be incorporated into the permanent welds. Generally, non-incorporated tack welds should be allowed to remain in Statically Loaded Structures, unless their removal is required in the contract documents. In tension zones of Cyclically Loaded Structures, non-incorporated tack welds must be removed. This topic is addressed in greater detail in AWS D1.1:D1.1M Section 7.17.

8.5.2. Is it necessary to remove arc strikes?

In Statically Loaded Structures[1], arc strikes need not be removed, unless such removal is required in the contract documents. However, in Cyclically Loaded Structures[2], arc strikes may result in stress concentrations that would be detrimental to the serviceability of such structures and should be ground smooth and visually inspected for cracks. This topic is discussed in AWS D1.1/D1.1M Section 7.28.

[1] Structures subject to loading that characteristically is slowly applied and removed, as would be typical in building, sign, and tower structures; dead, live, wind and similar loads are generally considered to be static.

[2] Structures subject to loading that is applied and/or removed at a rate that cannot be considered to be static and requires consideration of fatigue, as would be typical in bridge structures and crane runways.

8.5.3. What corrective procedures are required when distortion occurs from weld shrinkage?

Correction of distortion causes additional stresses. If the end use of the weldment does not justify corrective action, these stresses can often do more harm than good. Correction of out-of-tolerance conditions should be based upon requirements for structural adequacy and erection requirements.

Where distortion is anticipated it can be minimized with strongbacks, present assemblies, and balancing weld with appropriate joint details. It is difficult or impossible to predict or eliminate distortion in unique weldments.