Duct banks - heating PVC for the bends

The Greenlee PVC heater #847 helps get the blues outta the bends and saves a lot of money in couplings and prefabricated PVC bends. Overheating, however is a real concern and may lead to egg-shaped pipe. For best results set the timer, and be prepared with an extra hand in the ditch. In cold weather all of this is more critical as it may require 20+ minutes to heat a a single piece of PVC.

Photo
In the photo at left a piece has been overheated and removed. It's tricky to get the temperatures perfect in 15-20 degree weather - this piece'll be used for smaller cuts.

Tech specs
In general the older fellas on the site say they are comfortable getting ~22-45 degree bends in the pipe, and favor using couplings for anything over 10-15 degrees. Some of the younger and more ambitious guys swear they'll get several bends up to 90 degrees and beyond... am waiting to see it.

Tips
Probably the best thing to remember is that you need to heat the pipe only where you want to bend it. Most of the PVC heaters are ~4-6 feet in length and your pipe may be 8-10 feet long. Center the pipe where you know you need a bend and it'll save you time in the ditch.

Video - a nice 20-30 degree bend sent home (Rodney top, Ryan + Harley ditch)
Credits
Faulconer construction credits: Andy Fitzgerald = Superintendent - Greg and Dan Baily = foremen - Rodney on the top with the heater - Harley St Clair and Ryan in the pit