New Development of Seamless Steel Tube Manufacturing Technologies

The general development trend of seamless steel tube industry has been switched from output enhancement to product quality improvement,product mix expansion and operational cost reduction,resulting in a number of new equipment and technologies.Briefed in the paper are the development of seamless steel tube manufacturing technologies both at home and abroad.Other issues also involved here are a comparison of the application characteristics between the walking beam billet heating furnace and the rotary billet heating furnace,descriptions of the characteristics of such new processes and equipment as cone-type piercer,MINI-MPM,PQF MPM,semi-floating mandrel/on-line mandrel extracting processes,compact tube-rolling process,three-roll adjustment and quick roll change-over of stretch reducing mill and sizing mill,auto-control processes of tube quality（e.g.,the HGC control process for MPM and auto-control process of tube end upset and gage of stretch reducing mill）as well as steel tube on-line gage inspection process.