49 CFR § 192.715 - Transmission lines: Permanent field repair of welds.
Each weld that is unacceptable under § 192.241(c) must be repaired as follows:
(1) The weld is not leaking;
(3) Grinding of the defective area can be limited so that at least 1/8-inch (3.2 millimeters) thickness in the pipe weld remains.
(c) A defective weld which cannot be repaired in accordance with paragraph (a) or (b) of this section must be repaired by installing a full encirclement welded split sleeve of appropriate design.
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