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ASME B31.3 need to know allowable stress factor for API 5l X52 *** urgent response please ***

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APIpipeWholesaler

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Jul 26, 2012
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The engineer is stating per ASME B31.3 Table A-1 does not denote an allowablle stress factor for X52 in the table...

The Material is US made DSAW API 5L X52 PSL II 42" std (.375)

We substituted X52 for grade B and he is not allowing it?

He Writes:

HI Fred

I have communicated this information to the PEI at S***l, see his reply below.

Per ASME B31.3, there is no allowable stress value for API 5L X52 at the temperatures of this system. See snip below.


ASME_table_A-1_kg2uz5.jpg


I am seeking a rebutal to have him allow X-52 to be utilized for his application.

As always thanx in advance,

-=Fred=-

Vass Pipe API Line Pipe Industry Leader

People do what you inspect, not expect!
 
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As stated by the engineer and shown in the snip you posted, there is no allowable stress value for X52 (at 650°F) in B31.3 Table A-1. However, there is an allowable stress value for API 5L Grade B, which appears to be what they originally specified.

Don't substitute without the engineer's prior approval.
 
I would have not substituted without prior approval had the pipe company we sold the pipe to specified "B" on their order.

They only stated API 5L and when questioned they said ignore the MESC it's not important.

QUESTION: Is that actually meaning X52 is unacceptable above 400 degress or is it just not calculated in the chart for that temperature?

Capture_mov75c.jpg




Vass Pipe API Line Pipe Industry Leader

People do what you inspect, not expect!
 
The pipe company should not ignore requirements and/or substitute without documented engineering approval.

Section 323.2.4 gives the designer an option to use listed materials above their listed temperatures, but this requires data "obtained from a sound scientific program".

However, per Table A-1, note 55 is applicable to X52:
5L-Note_bt3k1x.png


Note 55 states:
Note55_tcjjdo.png


As a designer, even if I had sound scientific high temperature test data, I would not want to approve a material for high temperature service when B31.3 explicitly warns that this material is not intended for high temperature service and when other suitable material is a reasonable option.
 
Thank You Sir I do agree with your evaluation...

My customer will have to pay for their mistake.

-=Fred=-

Vass Pipe API Line Pipe Industry Leader

People do what you inspect, not expect!
 
API 5L X52, or any other material, is NOT TO BE USED at temperatures where allowable stress values do not appear. API 5L Grade B is also not allowed to bu used at those temperatures as well.
API 5L max Temp is 400

Reality used to affect the way we thought. Now we somehow believe that what we think affects reality.
 
7.0 - You're not in this instance correct, i.e. "Grade B is also not allowed to be used at those temperatures as well.
API 5L max Temp is 400"

API 5L Grade B does have a stress value at 650F in table A-1.

All the API 5L X-- grades finish at 400F, but Grade B doesn't.

I am simply amazed that the purchaser ( the mysterious pipe company) did not specify the grade of material they wanted.

You're going to have to trust me that the API 5L listed on the RHS is on the LHS 5L Grade B

image_x04byu.png


image_ij6xhp.png


Now why anyone wants to Use API 5L in this instance is a bit of a mystery when better steel grades are available or equal e.g. A106 grade B

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
Correct ASTM A106 B is preferred over API 5L

API 5L plainly states it is for pipe to be used in conveyance of oil, gas and water, however that is never done at 400+, Mismatched material.



Reality used to affect the way we thought. Now we somehow believe that what we think affects reality.
 
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