... . K7&K9&K8 3.ling according to ISO4179 ductile iron socket spigot pipe Standard: JIS, AISI, ASTM, GB, DIN, ENPlace of ... , mechanical properties are suitable to produce general purpose parts, cutting tools, mechanical parts, petroleum refining equipment, bolts and nuts, pump rods ... supplied with shipment, Third Part Inspection is acceptable. ductile iron socket spigot pipe