Interpretation: III-1-10-64
Subject: Division 1, NB-4121.3, Repetition of Surface Examination After Machining
Date Issued: December 2, 2011File No.: 11-1148
Question: If additional surface preparation, such as
grinding or polishing, is performed after PWHT and pressure testing, does NB-4121.3 require the
manufacturer to rep eat MT or PT after any su rface treatment (grinding or polishing)?
Reply: No, provided the metal removal does not exceed the
limits of NB-4121.3.
NB-4121.3 (b) the amount of material removed from the surface exceeds the lesser of 1⁄8 in. (3 mm) or 10% of the minimum required
thickness of the part.