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

Nothing brings folks together like running electricity

Nothing brings folks together like running water, electric, and HVAC lines in, plus raw sewage out.



Today's episode involves duct banks. Housed in PVC and encased in rebar reinforced concrete - underground duct banks make nice homes for 16000 Volt plus cables. The big fat kind that may arc flash and blow you to little bittie pieces. The kind that leave people looking for burnt embers to remember you by. So the specs on electrical duct banks are pretty tight... For more info on the safety for electricians go to OSHA's site



Anyhow, that's not really our deal - we prepare the lines. The prep work for duct banks may be done in the ditch or occasionally outside - really depends on the stretch being laid.

Helpful tools:
1) Tie wire and pliers - connect any overlapping seams, tie the pipe to the plastic seats, tie the rebar to the rebar and to the plastic seats... basically if it seems like it might wiggle free tie it down with plenty of tie wire.

2) Pipe primer and glue - here is a great video on glueing and priming PVC pipe

3) Sledge hammer and 2x4" beater block - especially with the larger lines 12"+ These lines may take a beating to get into place. Don't hit the plastic directly - it may snap - rail the back of a 2x4.