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View Full Version : Bending PVC Pipe w/Heat


ed2hess
03-17-2007, 11:31 PM
Is it possible to heat up this white pVC pipe with torch and bend it a little? I seen a electrical guy heat up and bend some of that grey plastic pipe.

crab
03-17-2007, 11:43 PM
Anything is possible,just keep that flame moving,PVC is hot hot hot!

MHM
03-18-2007, 12:18 AM
a torch will work, practice first. I use a electric heat gun when i can ( $20.00 at ACE)

jerryrwm
03-18-2007, 12:42 AM
You have to watch out that you don't heat it past the point of it being structurally sound. Too much heat and you will weaken the walls and therein lies the problem - leak down the road. The electrician could do it because there is no pressure on it. Just be careful.

PurpHaze
03-18-2007, 12:51 AM
They make a special pipe heater that you put in the section of pipe you wish to soften and bend. It's like a small oven with rollers on the bottom and a hood that comes down over the pipe. You insert pipe, turn it on and turn the pipe on the rollers as the section heats up. When the pipe softens then you remove it from the heater and slowly bend it to the shape you want... with gloves on to battle the heat. When the pipe cools it maintains the desired bend.

If I remember I'll take some pictures of our pipe heater on Monday. We don't use it very often but it's saved the day on a couple of tricky situations.

sildoc
03-18-2007, 01:19 AM
pulled out quite a few of these that break on the outside of the bend. I can see where it can work quite well but would plan on fixing that section in time. one was over 10 years old so there is hope and hey practice makes perfect right!

Az Gardener
03-18-2007, 02:12 AM
Just be careful when you heat the pipe it wants to flatten out. Wear thick gloves and roll it to keep it from flattening out. Be sure to use sched 40 pipe, no class pipe, too thin.

Hank Reardon
03-18-2007, 02:24 AM
I learned how to bend sch40 gray pipe over 20 years ago working as a yard hand for an electrical contractor. This was a huge outfit and we bent every sweep ell they used in the field from 1" up to 4". We used a large "bed" type heater like Purp mentioned with rollers.

Sure you may be screwing with the molecular structure of the material but as long as you don't expect it to be pressurized (why would you), you'll be fine. I've never seen any failures from it myself.

Here's a couple of hints: have a spray bottle handy to cool it down so it holds it's shape and you don't have to hold it for what seems like an hour. Also, when heating, I use arcs so the stop point is off the pipe. Have your jig ready and keep the torch moving constantly.

I still do it now for electrical work for offsets and sweep ells.

ed2hess
03-18-2007, 02:33 PM
Thanks for all the good input the install we are working on is pretty complicated due to the amount of obstacles. And the rock that we are running into keeps us from going into the ground to make these turns.

Dirty Water
03-18-2007, 02:44 PM
For the record, I've done some installs with some pretty bizarre angles, and I've never needed to bend pipe.

I'd do a stacked 90 or 45 over heating pipe, and you can get any angle you want out of that.

Wet_Boots
03-18-2007, 03:02 PM
Echo that. Fittings and glue are cheaper than heating equipment and the time it takes to use them.

Mike Leary
03-18-2007, 03:31 PM
I agree with Jon, I've thought of heating sch pipe over the years, but it's
always freaked me out. That's why we have 45 ells....now if spears/lasco
would make 22s...much easier. Mike Leary

Dirty Water
03-18-2007, 03:33 PM
I just thought of one install that I did that was very unusual. There was a landscape already installed that made great use of 3 and 4 man stones in its landscape beds and the beds themselves varied in height dramaticly. I had to run mainline through a lot of this area to get around a 30' drive. After having my guys hand trench through the beds, we ended up using 200' of 1" 200 PSI poly pipe for the mainline in this section, as it let me bend it around the rocks etc in ways that would have taken a long time with PVC.

I think thats the only time I've used that much poly on a job.

Mike, you can get 22.5 fittings from some manufacturers, but they usually are only 2" and larger.

Mike Leary
03-18-2007, 03:41 PM
The septic guys use a glueable bendable pipe w/special glue we have used
for laterals only with sucess, so far...I'd never use it on a main. I have used
poly also, but on long runs friction loss should be figured. Glue on!

Mike

Wet_Boots
03-18-2007, 03:47 PM
At trade shows, I've seen bendable PVC pipe. This before sch 80 unions became commonplace. The rep took the gleam from my eye by announcing that the flex pipe wasn't for continuous pressure.

Dirty Water
03-18-2007, 03:48 PM
I've seen up to two inch flexible PVC. It looks just like poly to the naked eye, but you can glue it.

I know a lot of pond installers use it.

Personally, I figure that a couple clamps and a insert fitting with some poly is good enough for me.

Mike Leary
03-18-2007, 03:50 PM
Yes indeed, not for continuous pressure, like Marlex ells, but I have used
it a lot for laterals.....it's the glue & prep, like everything in life>

Mike

Mike Leary
03-18-2007, 03:52 PM
Jon, I've used that flex PVC & had a very interesting service call one Saturday
morning!

Mike

Mike Leary
03-18-2007, 03:59 PM
The glueable pipe I'm talkin' about is white & anyone who supplies the septic
guys should stock it & the special glue.

Mike

londonrain
03-18-2007, 04:21 PM
The glueable pipe I'm talkin' about is white & anyone who supplies the septic
guys should stock it & the special glue.

Mike
We did a repair on a system that a pool contractor had damaged a few years earlier. They had damaged a 1 1/2" pvc main line and repaired it with the white flexible pipe. The pipe had a tiny pin hole in it. We uncovered the pipe and when we touched the pipe with the shovel another pin hole appeared. We tried a coupling for the repair but the pipe was so swollen a coupling would no longer fit. We ended up removing about 15' of the white flex pipe all the way back to the original 1 1/2" PVC.

Mike Leary
03-18-2007, 04:36 PM
I would think we'd have noticed problems with the pool pipe, but thank you
for your info. I love the term "touched with the shovel"
Mike

londonrain
03-18-2007, 05:10 PM
I would think we'd have noticed problems with the pool pipe, but thank you
for your info. I love the term "touched with the shovel"
Mike

I was pointing out why not to use this crap on main lines since you stated "I'd never use it on a main".

Mike Leary
03-18-2007, 05:50 PM
You is right: like slip-flixes, all of this is to try to get what the client perceives as overkill squared away without undue screwing around.
Bottom line: 45 ells & unions!
Mike

ed2hess
03-18-2007, 06:43 PM
For the record, I've done some installs with some pretty bizarre angles, and I've never needed to bend pipe.

I'd do a stacked 90 or 45 over heating pipe, and you can get any angle you want out of that.
Hard to do stack in a trench where I working with about 7 -8 " of soil and under it is very hard rock that would have to jackhammer. By stack I guess that is using a two ninety degree elbows and go vertical. Our first tool was valve finder the next will be one of those lightweight jack hammers operated off electric.

Mike Leary
03-18-2007, 07:19 PM
Hess pal....Valve locators will be one of the best investments you'll ever do:
Progressive Electronics has full line. I hate to say it, but we've used the baby
jack hammers & they work well; great for hi-pops too!
Mike

Dirty Water
03-18-2007, 07:54 PM
You can use two 45's to achieve any angle with only about 3" of height.

Of course, you could always just trench better angles :)

kerdog
03-18-2007, 08:08 PM
Saved as a bookmark a while back.....don't remember how I came across it at the time.....

www.pvcbender.com

kerdog

PurpHaze
03-18-2007, 08:34 PM
We've used the pipe heater less than 10 times in the past 20 years and probably only once in the last 10 and that was as a temporary fix to get a 2" lateral line around one root ball of a tree and between two other trees. I fully expected to have gone back in by now with the backhoe and totally renovate that end of the zone but it's still working. Everything we've ever used the heater on (all were repairs and usually with large tree roots in the area) is still holding together but the largest pressurized line was 2". :)

londonrain
03-18-2007, 09:06 PM
The breaker hammer we have works very well....I have cut 8" thick asphalt with the hammer.

ed2hess
03-18-2007, 10:19 PM
The breaker hammer we have works very well....I have cut 8" thick asphalt with the hammer.

Our business associate who does a lot of inside building plumbing brought one like that by and dug our holes for our back check. It worked nice, then he put a hole in the sidewalk to get wires up to side of the house. Did I remember correct that this is around $2K? And I wonder if they make any attachments that would assist in going under a drive.

PurpHaze
03-19-2007, 09:14 AM
The breaker hammer we have works very well....I have cut 8" thick asphalt with the hammer.

We have a Bosch electric hammer similar to this in our arsenal that we use on occasion where we don't want to tear up a large area but need the extra power to get through something especially hard.