PURPOSE: To suppress generation of spiral uneven thickness as well as shear deformation by reversing a rotating direction of the stock to be rolled of one or more skew rolling processes against a rotating direction of the stock to be rolled in the other skew rolling process.
CONSTITUTION: In the production line of seamless tube having a first skew rolling mill 10A and second skew rolling mill 10B, a skew angle β1 (+ direction) of a rolling roll 11 in the first skew rolling mill 10A and a skew angle β2 (- direction) of a rolling roll 11 of the second skew rolling mill 10B are reversed each other. At this time, a rotational direction of the stock to be rolled in skew rolling process by the first skew rolling mill 10A and a rotational direction of the stock to be rolled in skew rolling process by the second skew rolling mill 10B are reversed. By this method, generation of spiral uneven thickness is suppressed, further, the shear deformation generated in tube is suppressed so as to prevented the generation of inner/outer flaw.
| JP2021164955 | METHOD FOR MANUFACTURING SEAMLESS METAL PIPE |
| JPS6035204 | 【発明の名称】いおう快削鋼の継目無鋼管製造方法 |
YORIFUJI AKIRA
SHIMIZU TETSUO
Next Patent: PLUG FOR STRETCH REDUCING SEAMLESS STEEL TUBE