During the tacking of a pipe test coupon, when is the gap rod removed?

The gap rod is an important tool used during the tacking process of a pipe test coupon to maintain the proper spacing between the pipes being joined. Removing the gap rod before the third tack is the correct approach because it allows for the initial tacks to secure the position of the pipes while ensuring that they remain aligned and maintain their intended gap for welding.

By the time you reach the second tack, the alignment is sufficiently established, and the gap rod can be removed to facilitate access for the welding equipment. If the rod were removed after the first tack, there could be a risk of misalignment before the second tack is applied. Conversely, removing it after the third tack would not make sense, as the tacks would already be in place, potentially affecting the quality of the weld if the pipes shift.

In practice, this method maximizes the control over the gap and the integrity of the tacking process, ensuring that the ultimate weld is as strong as it needs to be.