For lap welded and riveted tanks, reinstallation of an original plate section that crosses an existing horizontal
seam is not permitted. Door sheets that cross vertical riveted or lap welded seams are not permitted in any case.
If a door sheet vertical cut-line crosses an existing seam in a butt-welded tank without an offset and the
removed section is reinstalled then additional weld examination shall be required at the intersection of the new
vertical weld seam and existing horizontal weld seam. In addition to the examination requirements of 188.8.131.52 the
back gouged surface of the root pass and the final pass (each side) of the new welds shall be examined by magnetic
particle or liquid penetrant methods. The existing horizontal weld seam intersected by the new vertical weld shall also
be examined by magnetic particle or liquid penetrant methods for a 6 in. distance on both sides.