3. Stamping of piece mark numbers on carbon steel pipe with steel die lowstress stamps is permitted if done lightly and carefully, so as to minimize notch effect, and so that the marking is not deep enough to cause cracks or to reduce wall thickness below the minimum allowed. Stamping alloy pipe is not permitted without Company authorization.
4. For color coding of fabricated pieces for large scale or multi unit projects, thermal transfer technology shall be used in the printing of the Color Code labels. Color Coding requirements are indicated in Specification L2CC-00050-SP-5030/SLCPL-50-09.