Originally Posted by JoeD
I don't remember how long it took. I only have a normal propane torch and I have used it for 3" copper drains. So it can be done.
Your skill level may be above average.
If I ever have to do this I guess I'd use two nozzles with flame spreaders to get uniform and quick heating. Maybe two propane canisters strapped together with a wedge-shaped spacer and hose clamps coupled end to end, so opposite sides of the joint get heated at the same time.