The welding gap must be checked at _________ locations.

The welding gap must be checked at three locations to ensure an even and consistent application of the thermite welding process. This practice helps to maintain uniformity in the weld and prevents issues such as misalignment or inadequate fusion. By checking at three distinct points, welders can detect variations or discrepancies in the gap that could affect the strength and integrity of the weld.

This method allows for assessment across the joint being welded, providing a comprehensive overview of the conditions under which the weld will be made. It is particularly important in thermite welding, where the precise alignment and spacing of the materials are critical to achieving the desired quality of the weld. Checking the gap at multiple locations increases the likelihood of catching any potential problems before the actual welding begins, minimizing the risk of defects in the final weld.