How to 'bend" a short pipe nipple.

Hap_Hazzard

@New England SteamWorks recently posted a beautiful solution involving bending a pipe nipple to the correct angle to connect two radiators in a bay window. But what if the nipple you need is too short to bend? I ran into this a few years ago when I renovated a bathroom and found I hadn't left quite enough room between the radiator valve and the wall. I had to use a new 2" nipple to adjust the height of the valve, and if I could only bend it a little, it would put the union of the valve far enough out to meet up with the radiator spud, but how in the world do you bend a 2" nipple? Here's how.

First make a clean diagonal cut at roughly ½ the complement of the desired angle, then chamfer the outside edges of both pieces, as shown.

Now you can rotate the pieces to create the exact angle you need.

Clamp the pieces in a vise.

Now you can weld a bead into the groove created by the chamfers.

I use a cheap wirefeed welder with flux-core welding wire. I'm not a great welder by any stretch, but these machines make it super easy to make good, air-tight welds.

ethicalpaul

Let's see the weld!

Hap_Hazzard

You're just going to have to use your imagination.

I didn't take any pictures of the finished product because it didn't look pretty enough. I meant to re-do it, but never got around to it. Now I wish I'd just taken some pictures, because it would have made the point that it doesn't need to look good to work.

The important thing is to grind the chamfers exactly as I've shown them so the weld just penetrates to the inside of the pipe, so when you run your finger around the inside, you feel a slight bump instead of a crack. Unfortunately I couldn't take a picture of the inside.

SteamingatMohawk

Nice, and it's not like the copper tubing connecting two radiators pic in the discussion, "So There's This Nice Woman...." .

I wonder if any company makes spherical unions.

EBEBRATT-Ed

You could heat a nipple with an oxy acetyelene torch and bend it but not one that short.


Doing that is fine if you have the time, most contractors are going to find another way. Time =$$$$$

Suppose you could silver solder it as well

Hap_Hazzard

EBEBRATT-Ed said:

Suppose you could silver solder it as well

If I were using a torch I'd be inclined to braze-weld it. I have a gas welding setup, but every time I go to use it, the 0₂ tank is empty, so I don't bother with it anymore unless I'm going to be doing a lot of welding/cutting.

Hap_Hazzard

EBEBRATT-Ed said:

Doing that is fine if you have the time, most contractors are going to find another way.

Most contractors are going to leave enough room between the valve and the wall in the first place.