Product Introduction API 5L line pipe (Seamless and welded pipe) of all grades have PSL1 and PSL2 two product specifications, they are different on chemical composition, manufacturing processes, mechanical strength, heat treatment, test records, traceability etc. PSL is the short name of product standard level. The product standard level of line pipe have PSL1 and PSL2, also we could say the quality standard divided in PSL1 and PSL2. PSL2 is higher than PSL1, not only the inspection standard is different, also the chemical property, mechanical strength standards are different. So when place the order for the API 5L line pipe, there should be stated clearly for the size, grades these general specification, also have to clarify the production standard leve, PSL1 or PSL2. Product Specification Description Spiral welded steel pipe, Straight seam welded steel pipe, Carbon steel tube, …