| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce wear of side-surface dies attached to a roll member of a mandrel of a ring rolling mill. <P>SOLUTION: The ring rolling mill includes the mandrel 2 in which a first side-surface die 6 is attached to one end portion of the roll member 5 freely attachably/detachably and a second side-surface die 7 is attached to the other end portion, the ring rolling mill performs rolling of a ring-shape workpiece W into which the roll member 5 is inserted, between the mandrel 2 and a rotationally driven main roll 1 while suppressing the width-direction deformation of the workpiece W by both side-surface dies 6, 7. The ring rolling mill further includes a mandrel driving device 4 which rotationally drives the mandrel 2 in a rolling direction beforehand upon rolling the workpiece W, thereby the mandrel 2 is brought into contact with the workpiece W in a dynamic friction condition upon starting the rolling, consequently wear of the roll member 5 and both side-surface dies 6, 7 of the mandrel 2 is reduced compared to the conventional ring rolling mill which starts rolling from a state in which the mandrel 2 is in a static friction condition. <P>COPYRIGHT: (C)2012,JPO&INPIT |
