How to Fix PVC, CPVC and ABS Pipe that has Gone Out of Round
Q: I have a stack of PVC pipe sitting outside in the weather and it has been there for several hot summers. The heat causes the ends of the pipe, in particular, to become squared slightly and difficult to fit into a fitting socket because it is no longer perfectly round. What can I do to re-round the pipe?
A: Use a PIPE DEBONDER tool, which is normally used for ungluing broken plastic pipe from glued fittings.
The heat from a debonding cycle can be used to soften the pipe sufficiently to allow it to be removed from a fitting. It can also be used to re-round pipe ends to their original perfectly round shape.
Using the next smaller size thermal cycle (for example if you have 3 inch pipe that is be re-rounded, use the 2.5 inch cycle for the same schedule (wall thickness) as programmed into the PIPE DEBONDER. The heating of the inside of the pipe will relax the pipe and allow the stacking stresses to be relaxed to where the pipe can obtain, on its own, its original round shape. When it cools, it can be inserted into the fitting it is to be cement bonded to.
Another trick is to slip on a coupling of the same size to the end of the pipe to force it round. After a few minutes to cool, the pipe will stay round for a long time.