Elbow cut 45 degrees to 27.5 degrees on a 10-inch branch of the pipeline 4

[abdolmaleki1975]

Dear Friends
I wanted to know if it is possible to cut a 45 degree elbow to 27.5 degrees in code ASME B.31.8.
Is there anything in ASME B.31.8 about this?
Is this allowed?

 

[LittleInch]

Yes this is possible.

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

 

[LittleInch]

How have you got such a strange angle?

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

 

[IFRs]

NOthing wrong with cutting elbows, much much much better than mitering the pipe

 

[abdolmaleki1975]

Thanks for answering my dear friends
I am from the engineering department, and my colleagues in the execution department collided with a water pipe while working, causing the water pipe to rupture and inevitably following an imposed angle.
Now they are asking us for approval for their work
I humbly ask you to let me know if there is an approach code to confirm by mentioning its reference in the code.

 

[abdolmaleki1975]

Even in code asme B 31.8 ?
It should be noted that this is a 10-inch line that branches from a 30-inch line with a pressure of 1050 psi. (To enter a city to supply gas from the pipeline to the distribution system, but the pressure is still 1050 psi)
It is very important that I have a standard reason for approval

 

[weldstan]

There is no prohibition of doing so in B31.8, so you can do it. However, making the weld of the cut end to straight pipe may prove quite difficult, but not impossible.

 

[LittleInch]

OK.

I don't fully understand your requirement, but the relevant section is 841.2.3 c)

c) Elbows. Factory-made, wrought-steel welding
elbows [highlight #FCE94F]or transverse segments cut therefrom[/highlight] may be
used for changes in direction, provided that the arc
length measured along the crotch is at least 1 in. (25
mm) on pipe sizes NPS 2 (DN 50) and larger.

The relevant bit is highlighted. Transvers segment means they you cut the elbow at 90 degrees to the axis of the elbow. So find the centreline of the elbow and make the cut at 90 degrees to that centreline.

Is that what you were looking for?

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

 

[abdolmaleki1975]

My dear friend LittleInch,
I saw this section of the code(841.2.3), but another section of the code occupied my mind, and that section was 831.3.2 and 831.3.6 a,b,c .
I thought maybe the "differing from those of regular shape" meant a change in the dimensions and sizes specified in the standard tables of Asme16.9 or MSS sp75 (for example the dimensions A and B and the angle have changed).
Anyway, thank you very much for your help and guidance and I am happy with your friendship

 

[LittleInch]

Abdol,

Section 831 really means if you had an elbow which wasn't circular but elliptical, or a radius which wasn't the same.

It doesn't mean that you can't cut an standard elbow to the angle you want. This is done many times a day all over the world.

Beware that you need to buy some good elbows which are uniform thickness around the forging and are round all the way around. Some cheaper / poor quality elbows can vary in wall thickness and also might not be round when you cut them so you would then have difficulty welding a round pipe to an oval fitting(!)

Get the supplier to cut it and let them find a good elbow which has the same wall thickness at both ends and is perfectly round.

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

 

[abdolmaleki1975]

Dear LittleInch;
Thank you very much for your guidance