| ‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘ KAWASAKI STEEL TECHNICAL REPORT No.38 ( April 1998 ) Ironmaking Technology and Tubular Products Technology ‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘ |
| High Speed Production Technology for ERW
Stainless Steel Pipes without Lubrication Takaaki Toyooka, Yuji Hashimoto, Makio Gunji |
| Synopsis: In order respond to the tendency of using stainless steel for automotive exhaust pipes, a technology of manufacturing high quality ERW stainless steel pipes has been needed. Roll marks and penetrator defects of welded seam due to formation of oxides easily occur during the manufacture of ERW stainless steel pipes because the physical properties of stainless steel are different from those of carbon steel. In the conventional forming process, lubrication is necessary to prevent roll marks. However lubricant is a cause of deterioration of welded seam quality. Kawasaki Steel developed a mill using a new forming process. It is the CBR (chance-free bulge roll) forming mill that can manufacture high quality ERW stainless steel exhaust pipes with excellent formability. It has achieved high quality of welded seam in welding with a speed as high as 110 m/min and the suppression of roll marks without lubrication. |
| TextiPDF: 8p./368kbj |