[MW:13587] RE: 13583] Pipe damaged during fabrication

// I have problem in our site that, we found some fabricated pipes ( as per B31.3) the parent material thickness reduced by grinding (or due to any handling mark) more than 12.5% is not acceptable,//

I would like to clarify that, the 12.5% reduction in thk, mentioned by you is taken from material specification. Not from ASME B31.3. B31.3 specifies only the minimum thickness. See 304. So, it is Designers decision to say whether this piping can withstand the intended service or not.

See 328.4.2 (b)(4) and 328.4.3(c) for base metal repairs pertaining to alignment. But, for base material repairs on other areas, B31.3 neither specify nor prohibit.

In these situations, If the thickness is found to be less than the minimum required thickness, and confirmed by Designer/Owner,

you may do the repair as per material specification and carryout the necessary inspection.

Note that any repairs on the parent material requires owners/purchasers prior approval and done with the qualified procedure/welders.

M.Vijayan

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of jesti fer
Sent: Monday, January 30, 2012 5:23 PM
To: materials-welding@googlegroups.com
Subject: [MW:13583] Pipe damaged during fabrication

Dear Experts,

I have problem in our site that, we found some fabricated pipes ( as per B31.3) the parent material thickness reduced by grinding (or due to any handling mark) more than 12.5% is not acceptable,

is there any possibility to build up (Buttering) the base metals. Where can I will get the reference

jestifer

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