... welded pipe.c Specification: ASTM A53, A106, A179, API 5L, Seamless Carbon Steel Pipecarbon steel seamless & welded pipe.c Specification: ASTM A53, A106, ... A179, API 5L, BS1387... Surface: Black, black varnish coating, zinc- ... ~ Sch160 High quality, multi-specification, low price, quick delivery. seamless steel tube