Weld-o-let on elbow

[Singhnishesh]

Please find attached an image of my current project. Please advise if the weld-o-let shown in the image is allowed. I could not find any details from ASME or other standards. The elbow size is 16" LR and wel-o-let is 16" x 1". Any evidences if it can be done will greatly be appreciated.

 

[Snickster]

Elbolets are used on elbows.

 

[Snickster]

See attached Olet catalogue page 25. It is an old catalogue but you can get the latest from the manufacturer website.

 

[LittleInch]

Nothing attached!

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[IFRs]

I don't think the Elbow-Let is what the OP is needing - it looks like they are adding a thermal relief or small take-off to the top of the flat elbow.

 

[LittleInch]

That looks like a very very big flange and weight all sitting on a 1" weldolet?? What pressure rating do we have here?

It's certainly not usual as there will be some curvature in both directions, but I doubt you will find anything that says yes or indeed no.

Having said that, elbowlets are allowed which is just a different version of this ( a reinforced branch fitting welded to another forged fitting) B16.9 seems to sat this sort of thing falls into B31.3 piping specification area, not the fitting itself. But it's very vague.

My instinct is to say no, the elbow is a forging in all likelihood and may not have equal wall thickness.
But also on the grounds of workmanship and potential fouling of the studs and nuts on that main flange. So either put it in the middle of the elbow or on the next straight bit.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[XL83NL]

Elbolets are used on elbows.

Correct, but this a weldolet.

Weldolets are also used on elbows, in the configuration shown above.

Does the Code allow this practice? No, I think not. The elbow is likely considered an unlisted fitting now.
Is this method used more often for Code applications, without further/additional calculations? Yes, I think so.

Huub
- You never get what you expect, you only get what you inspect.

 

[IFRs]

What is the function of the OLet? If you need a pressure tap maybe drill the flange or buy a drilled flange? If it has to be a branch connection, do you have room to put a short section of straight pipe there and then the elbow? You can also try to buy a long-tangent elbow which would have a straight section that you could tap into.

If the service is not severe and the pipe stresses are low what you have shown may work. On a 16" elbow, the curvatures may not be an issue for a small fitting. I don't think you will find it in any code, either prohibited or described.

 

[racookpe1978]

I share Little Inch's reservations about the access to the large flange nuts and bolts for removal (of the bolts/studs) and torqueing of the nuts. (Add access and torqueing of the small flange nuts and fasteners too.) To resolve assembly and maintenance concerns, move the fitting out towards the curve of the large elbow.

Weight and load of the "smaller" piping and its flanges needs to be specifically addressed and calculated for the weld itself around the bottom of the elbowlet, AND for the added weight and loads on the elbow and pipe assembly and its pipe supports as a whole. NOT guessed at or washed over. Might be okay, either might be a trouble spot. Too close to margins to just assume.

Elbowlet? No, not here for this application. Those are shaped to go into the extrados "outer curved side" of an elbow to "poke a hole into the pipe" that will be "aimed" at the axial centerline of the inlet or exiting pipe attached to a 90 degree elbow. Here, the weldolet is "aimed down" into the radial axis of the elbow.

 

[pmover]

Agree, the elbow fitting is altered; hence, it needs to be qualified.
Yes, i have observed locations where fittings are altered, whether or not the fitting was qualified, i have no idea.

Fyi, elbolets are made for this purpose.

 

[racookpe1978]

An open question about pipe supports in that 3D image. How is the sliding small pipe support under the 1 inch (1/2 inch ?) pipe coming off the bottom of the large elbow expected to "only carry" the small weight of the 1 inch pipe?

Would not the massive weight of the large pipe and its fittings and the weight from above the elbow "naturally" come down through the weldolet to the support unless a very-carefully balanced spring hanger were holding up the elbow? ?