Abstract: The production and manufacture technology of HFW steel pipes have been developed so quickly, thanks to application of relevant newly developed equipment and a number of new techniques to manufacture of the medium-sized HFW pipes, including the FFX forming and sizing process, the hi-frequency welding process, the weld seam heat treatment and NDT, etc. Medium-sized HFW pipes have been widely used in the offshore and inland oil conveyance sectors. Over the recent years, the application scope of such pipes are further expanded owing to the development of the X80 linepipe and the TUF oil well pipe. Elaborated here in the article are the technological features and advantages of the medium-sized HFW mill based on analysis of the HFW 508 Pipe Mill located in North Petroleum China Steel Pipe Co., Ltd., Yangzhou Branch.