Ream all cut tube ends to the full inside diameter of the tube to remove the small burr created by the cutting operation. If this rough, inside edge is not removed by reaming, erosion-corrosion may occur due to local turbulence and increased local flow velocity in the tube. A properly reamed piece of tube provides a smooth surface for better flow.
Remove any burrs on the outside of the tube ends, created by the cutting operation, to ensure proper entrance of the tube into the fitting cup.
Tools used to ream tube ends include half-round or round files (Figure 7.3), a pocket knife (Figure 7.4), and a suitable deburring tool (Figure 7.5). With soft tube, care must be taken not to deform the tube end by applying too much pressure.
Soft temper tube, if deformed, can be brought back to roundness with a sizing tool. This tool consists of a plug and sizing collar.
Figure 7.3. Reaming: File
Figure 7.4. Reaming: Pocket Knife
Figure 7.5. Reaming: Deburring Tool