2012 年 53 巻 616 号 p. 445-449
Hot ring rolling is a useful process for producing large seamless rings. The ring rolling mills are classified into two types, i.e., two-roll-type and three-roll-type by roll layout. In our previous studies, the deformation characteristics in the three-roll-type ring rolling process have been investigated experimentally and numerically. In this study, a numerical simulation of the asymmetric product was performed by FEM together with the ALE method. The relative velocity between the ring and the rolls in the three-roll-type ring rolling process is low compared with that in the two-roll-type ring rolling process because of the roll layout. The reduction in the relative velocity improves the surface condition of the material and roll life. In the three-roll-type ring rolling mill, the rotation axes of the two main rolls lean from the horizontal axis. Therefore, the circumferential velocity of the main rolls has a transverse component in the roll bite. This velocity component introduces ring deformation toward the z-direction in the roll bite. In the production of asymmetric products, three-roll-type ring rolling has an advantage of formability over the two-roll-type ring rolling.