... rolled, cold-rolled or cold call is made. Seamless steel pipe with a hollow cross section, a large number of channels ... for transporting fluids, such as steel pipe and solid steel bar, compared with the same torsional strength in ... B,X42,X46,X52,X56,X60,X65,X70,X80 API SPEC 5L,GB/T9711.1,GB/T9711.232-1240*3-100For ... , water and oil in the short-distance transport. Seamless steel Pipe