Welding a Structural Lifting Bracket to a Pressure Containing Pipe.

[victor007]

Hi, I am going to weld a structural lifting bracket onto a pressure-containing pipe.
I know ASME B31.8 calls some requirements under clause#831.3.5.
Few questions:
1-Is there any other codes call the resuirements for the design, application, and testing for such setup? If "Yes" please reference in detail, not just calling the code name.
2- Do you think the weld desing is a function of stress level in the pipe under pressure?
Thanks, Victor

 

[MikeG7]

Victor, don't know that code, but on your 2nd point , probably lifting attachment is not in use when pressure exists so for that reason the lug weld design is not pressure dependent. Fatigue...unlikely, especially if material expansions are identical. Just thoughts, not answers...

 

[JStephen]

Are you welding a new lug onto an existing pressurized pipe while it is pressurized? Or is this a lifting lug for handling a pipe that will be pressurized at some later time?
Your post sounds like the first choice, Mike's response sounds like the second choice.

 

[chicopee]

I would think that a split collar with a lug would be better choice than welding a lug on a pipe under pressure.

 

[victor007]

@JStephen, Lifting lug is for handling purposes only, and pipe is not presurized during lifting/handling.
I am asking about any requirements for this weld in terms of Design criteria, welding, and tests (NDEs), the pipe will be presurized later. So, to me this weld is slightly different thant welding a structural element to another one. Because the pipe will be presurized later, I thought there might be some special requirements for that weld to make sure it does not create a weak point on the pipe.
Thanks, Victor

 

[chicopee]

I don't understand the reason for a lifting lug on a pipe. How big in diameter, length and weight is that pipe?

 

[weldstan]

You should design for the weight to be lifted. AISC can be used as a guide.

 

[gr2vessels]

Hi Victor, your lug is no different from other similar lugs or trunnions you might use in operation for pipe support. Obviously, there are welding requirements and perhaps relieving requirements, but no particular stress calculations since you don't penetrate the pressure retaining envelope. You size correctly the lug for the weight or the lifting loads and the fillet weld attaching the lug to the pipe.
Cheers,
gr2vessels

 

[victor007]

Thanks to every one responding back to my question.
Victor.