Which type of air-powered chisel is used to cut the old tube flush with the drum or header?

The type of air-powered chisel used to cut the old tube flush with the drum or header is a side cutting chisel. This design allows for a precise and flat cut at the surface level, making it particularly effective for removing tubing without leaving protrusions that may interfere with the installation of new components. The cutting edge of the side cutting chisel is oriented to facilitate this type of flush cutting, ensuring that the surface remains clean and smooth.

In contrast, flat cutting chisels are typically designed for broader surface areas and may not achieve the flush cut required in this scenario. Pointed cutting chisels are generally meant for creating holes or making initial penetrations rather than flush cuts. Heavy-duty cutting chisels, while robust, are more geared towards thicker materials or situations requiring more force, which may not provide the level of precision needed for flush cuts.

Thus, side cutting chisels are specifically chosen for their ability to effectively and cleanly cut tubes flush with other components.