Imperfection : An imperfection is a discontinuity or irregularity in the produce. For exact definitions and illustrations of specific imperfections see API Bulletin 5T1. Sometimes called a flaw. (RP 5A5)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}