Pipe Wall Thickness
Pipe Wall Thickness
(OP)
Hi everybody,
I have read about pipe wall thickness calculation using B31.3 and I have seen that the final wall thickness considers manufacturer's tolerance (For Example, 12.5% for A106).
My question is ¿do I also have to consider this manufacturer's tolerance when I'm calculating under other B31 codes (B31.4, B31.8, etc)?
Thanks a lot.
I have read about pipe wall thickness calculation using B31.3 and I have seen that the final wall thickness considers manufacturer's tolerance (For Example, 12.5% for A106).
My question is ¿do I also have to consider this manufacturer's tolerance when I'm calculating under other B31 codes (B31.4, B31.8, etc)?
Thanks a lot.





RE: Pipe Wall Thickness
http://virtualpipeline.spaces.msn.com
"We can't solve problems by using the same kind of thinking we used when we created them." -Albert Einstein
RE: Pipe Wall Thickness
The 31.8 considers the underthickness tolerances in the wall thickness calculation by means of Basic Design Factor.
So you DO NOT need to consider it separately in wall thickness calculation.
(refer section 841.11 ASME B31.8)
regards
Siddharth
These are my personal views/opinions and not of my employer's.
RE: Pipe Wall Thickness
"If pipe is ordered by its nominal wall thickness, the manufacturing tolerance on wall thickness must be taken into account. After the minimum wall thickness is calculated, this minimum thickness shall be increased by an amount sufficient to provide the manufacturing tolerance allowed in the applicable pipe specification or required by the process."
It's similar to the "c" adder (mechanical allowances) in B31.3 (Process Piping, 2006), para 304.1.1, although it doesn't describe it as explicitly in this code.
RE: Pipe Wall Thickness
RE: Pipe Wall Thickness
jt
RE: Pipe Wall Thickness
RE: Pipe Wall Thickness
Please start a new thread for your question
JB