| 摘要 |
PROBLEM TO BE SOLVED: To prevent the seizure of a mandrel in the rolling of a seamless steel tube. SOLUTION: In the rolling of the seamless steel tube, the mandrel drawn out from the tubing after the rolling is immersed in cooling water containing salt so that a salt coat of 0.5 to 2.5 g/m<SP>2</SP>is formed on the surface of the mandrel. This prevents the seizure of the mandrel, lengthens the life of the mandrel and decreases flaws inside the product. COPYRIGHT: (C)2004,JPO |
