Non-standard bend in schedule 40 DWV?

[Mark G.]

Good evening.

I am connecting 3" schedule 40 DWV pipe to an existing tile line, and I really need a fifteen degree bend. Any suggestions? Can I get away with heating and bending this stuff?

Thanks

-Mark

[Mark G.]

And the answer is...the pipe heats and bends pretty well. I suppose it's code violation, but the pipe is only carrying runoff so what the heck.

[PeterD]

Perhaps. Fill the pipe with *dry* sand before trying to bend it. Work carefully. The sand will keep the pipe from collapsing at the bend, but becareful of what you are doing, watch the bend for distortion.

[DT]

They make heaters just for this purpose for PVC. They are an electric heating pad that wraps around the pipe. For what you need you can get away with using a heat gun. Packing with sand as another poster said can help. If you are bending near the end of the pipe, be sure and trial fit it into a matching socket while it is still hot to make sure it is still round.

[Mark G.]

Good advice, thanks to both of you guys. I'll remember the sand for next time. My bend does have some rippling, but I don't foresee a problem in this application. The bent section will be on a 45-degree slope, and the bend is within a foot of the connection to the catchbasin. I only anticipate rainwater going through it, so there shouldn't be a problem.

-Mark

[Mark G.]

Thanks for the advice.

Do plumbing codes typically allow heat bending of 3" schedule 40 DWV pipe, assuming that proper equipment and techniques are used?

-Mark

[HerHusband]

Mark,

I wonder if you used one of those rubber couplers (like Fernco style), if that would give you enough flexibility to bend fifteen degrees?

Or, if you have some working room, maybe combine a couple of 22.5 degree elbows to get just the right angle?

Just some options...

Anthony

[Mark G.]

Mmm...maybe. I _was_ planning to use a rubber donut, but I can't find the correct size at any of the suppliers around here (the closest size donut is about 1/8" too large for my clay pipe.) In the end I went ahead and bent the plastic pipe using a heat gun.

I tried a pair of 22.5 degree bends, but I couldn't get the slope I wanted without a change in direction. Should it be possible to do this with a pair of 22.5 bends?

-Mark

[DanG]

If elevation will allow, you can install a T or, preferably, a wye in the terra cotta line facing straight up with a 90° el or turned at a 45° up with a 45° fitting to receive the drain pipe. This would be the most professional solution.

[HerHusband]

I have no idea... I'm just throwing ideas out there. :) Helpful, huh...

I only mentioned it because I had to line up a couple of drain pipes when I plumbed our house a few years back. One was the main drain coming from the foundation, the other was the drain line going to the septic tank. They were "almost" lined up, but probably off by a few degrees in every direction. Thankfully, I had a slight drop I could work with, and I was able to line everything up using three 45 degree elbows. It took some head scratching and experimentation, but it worked out great in the end.

Anthony

[Dennis]

Consider using a flexible coupling to make the offset. I've never done this, but it should be possible to make a 15 deg bend.

(example).

If height isn't a factor, you assemble a street and regular 1/16 to make the required bend. NIBCO makes (or used to make) a 11-1/4 deg in copper (don't know about ABS or PVC.) Available 1-1/4" thru 6", might be close enough.