As the technology of continuous
casting developing, a lot of billets of horizontal casting are used to pierce directly in production of seamless steel tube .But as well as the applicaton of horizontal
continuous casting billets , the amount of disfigurement of
pierced shell inner and
outer fold is increasing apparently,especially the outer fold is the very seriousone. As the example of a certain tube plant in Chengdu, outer fold took up 93.3% of the amount,and the economic losts is nearly 3 million yuan per year. This paper studies the affection of piercing process factors to the shell’s outer fold of continuous casting
billets. It can reduce the pierced shell’s
Outer Fold defects greatly and improve the rate of metal utilization by reducing properly the distance of guiding plate, increasing the distance of roll grinders and reducing the eclipse degree. It can also get the same result by raising the tube billet’s heating temperature and prolonging its heating time. The production practice demonstated that according to the technics project,the outer default can be reduced to 40.75%,the economic benefit are remarkable.