| 摘要 |
<p>PROBLEM TO BE SOLVED: To solve such a problem that the out-of-roundness of a steel tube is degraded when unfilling that noncontact part with a grooved roll in the stand before the final one is produced in a part of the outside surface of the steel tube at sizing is generated. SOLUTION: This device is a sizing device 10 which is provided with a sizing mill 11 for steel tubes 60 provided with nine stands F1-F9 having three grooved rolls a, b, c, an outside diameter measuring device 41 for measuring the outside diameter d1-d3 of a cross section of the steel tube 60 rolled with the sizing mill 11 and a controller 51 for controlling the screw-down location of at least one grooved roll among the grooved rolls a, b, c which belong respectively to the stands F1-F9 based on informations about the center position of the steel tube 60 which are determined from the measured values d1-d3 of the outside diameter measured with the outside diameter measuring device 41, that is, a center position presenting region in which the center position of the steel tube 60 is present.</p> |
