ASME B31.1

Yes,

A: Additional thickness, There are three different conditions.

1.-To compensated matl. removed in threading, grooving, Transition for welds....

2.-To compensate the mechanical strength of the pipe, like supports, temp. expansions........

3. To provide the corresponding corrosion allowance, for service, Temp............

That is why you do not find an specific value, you have to assume it.

ASME B31-3 Page 21 Parr. A.6 Edition 2010 Table 103.4.7

Regards, WP

By your id, I'll assume you are in school or newly graduated. Welcome to the wonderful world of codes. I no longer have access to latest codes, but found B31.1 2001 at http://pbadupws.nrc.gov/docs/ML0314/ML031470592.pdf (not sure how the guvment gets by with re-printing copyrighted material, but we'll use it). I'll assume this is the same as the version you are using. You are confusing paragraphs and tables.

(A.6) A = additional thickness, in. (mm):

(A.6.1) to compensate for material removed in threading, grooving, etc., required to make a mechanical joint, refer to para. 102.4.2;

(A.6.2) to provide for mechanical strength of the pipe, refer to para. 102.4.4 (not intended to provide for extreme conditions of misapplied external loads or for mechanical abuse);

(A.6.3) to provide for corrosion and/or erosion, refer to para. 102.4.1;

Once you go back to those paragraphs, it should make sense. Speed reading is not a virtue when trying to digest codes. I attribute my current slow reading affliction to too many years of having to dig out the meaning of such engineering documents. Sometimes, you just have to leave it for a while and come back later.

Hi Bigg, Also speed writing to reference codes is not a virtue. You are right is: 102 no 103. Regards. WP

I see my mistake, I misread the code alright, thanks for the input.