ASME SA 335-2013 pdf download.SPECIFICATION FOR SEAMLESS FERRITIC ALLOY-STEEL PIPE FOR HIGH-TEMPERATURE SERVICE.
6. Chemical Composition
6.1 The steel shall conform to the requirements as to chemical composition prescribed in Table 1.
7. Workmanship, Finish, and Appearance
7.1 The pipe manufacturer shall explore a sufficient number ofvisual surface imperfections to provide reasonable assurance that they have been properly evaluated with respect to depth. Exploration ofall surface imperfections is not required but may be necessary to ensure compliance with 7.2.
7.2 Surface imperfections that penetrate more than 12 1 ⁄ 2 % of the nominal wall thickness or encroach on the minimum wall thickness shall be considered defects. Pipe with such defects shall be given one of the following dispositions:
7.2.1 The defect may be removed by grinding provided that the remaining wall thickness is within specified limits.
7.2.2 Repaired in accordance with the repair welding pro- visions of 7.6.
7.2.3 The section of pipe containing the defect may be cut off within the limits of requirements on length.
7.2.4 Rejected.
7.3 To provide a workmanlike finish and basis for evaluat- ing conformance with 7.2, the pipe manufacturer shall remove by grinding the following:
7.3.1 Mechanical marks, abrasions (see Note 5) and pits, any of which imperfections are deeper than 1 ⁄ 16 in. [1.6 mm]. N OTE 5—Marks and abrasions are defined as cable marks, dinges, guide marks, roll marks, ball scratches, scores, die marks, and the like.
7.3.2 Visual imperfections, commonly referred to as scabs, seams, laps, tears, or slivers, found by exploration in accor- dance with 7.1 to be deeper than 5 % of the nominal wall thickness.
7.5 When imperfections or defects are removed by grinding, a smooth curved surface shall be maintained, and the wall thickness shall not be decreased below that permitted by this specification. The outside diameter at the point ofgrinding may be reduced by the amount so removed.
7.5.1 Wall thickness measurements shall be made with a mechanical caliper or with a properly calibrated nondestructive testing device of appropriate accuracy. In case of dispute, the measurement determined by use ofthe mechanical caliper shall govern.
7.6 Weld repair shall be permitted only subject to the approval of the purchaser and in accordance with Specification A999/A999M. ASME SA 335 pdf download.