Need your Help- Compressors small bore piping failure

[HamzaNossair]

Hello,

Please help me understanding the following:-
It appears in my plant when small pipings is connected to large bore piping on the discharge of a rotating equipment, the vibration stress appears to cause fatigue in the welds at the small bores?

what is your advise?
At what piping size ( 2'' or so maybe), the support shall be enforement.

The application is Centrifugal Compressors.

 

[BigInch]

2" piping connected in the vicinity of compressors should be XXS. Distances between supports should be kept short, 2 meters max.

What would you be doing, if you knew that you could not fail?

 

[HamzaNossair]

Can you advise, what do you mean by XXS?
Also, Which distances between supports?

 

[BigInch]

XXS = eXtra, eXtra, Strong. A very common, standard designation for pipe wall thickness that you should know.

2 meters

What would you be doing, if you knew that you could not fail?

 

[JJPellin]

We have seen similar failures in a couple of our large machines. We add gussets to support small bore connections (generally 1" or smaller). As BigInch notes, the pipe should be XXS or schedule 160 for these small lines.

Johnny Pellin