论文部分内容阅读
本发明提供一种无缝钢管的制造方法,该无缝钢管的制造方法可以降低芯棒式无缝钢管轧机进行拉伸轧制时的摩擦因数、减少钢管的内表面缺陷的产生。在延伸轧制空心管坯时,在芯棒的表面涂敷以石墨和云母中至少一种为主要成分的润滑剂,并对空心管坯的内表面供给以1价碱金属的硼酸盐为主体的润滑剂,使延伸轧制满足下述条件:(a)穿孔刚结束时的管坯内表面温度为1150℃以上,从穿孔结束到供给以1价碱金属的硼酸盐为主体的润滑剂为止的时间,
The present invention provides a method of manufacturing a seamless steel pipe that can reduce the friction coefficient during the drawing and rolling of the mandrel mill and reduce the occurrence of inner surface defects of the steel pipe. In the case of drawing and rolling a hollow shell, a lubricant containing at least one of graphite and mica as a main component is applied to the surface of the mandrel, and the inner surface of the hollow shell is supplied with a monovalent alkali metal borate as (A) the temperature of the inner surface of the shell at the moment immediately after the piercing is 1150 ° C. or more, and the lubricant mainly composed of the monovalent alkali borate is supplied from the completion of piercing The time until the agent,