Laminations are internal metal separations that are generally parallel to the surface of a pipe. Slivers and scabs are pieces of metal that have been rolled into the surface; scabs are usually due to casting defects while slivers are introduced during rolling. Inclusions are foreign or nonmetallic particles that are trapped during steel solidification.
Pipeline Operators are allowed to repair certain defects, such as, cracks, gouges, hard spots and stress corrosion cracking by grinding them out of the pipe. The grind defect is assessed the same way one would assess external corrosion, assuming the COMPLETE removal of the altered metallurgical area.
