PURPOSE: To prevent coming down of a mandrel due to reaction from material acting on the mandrel by incorporating a pair of back-up rollers allowing rotation in a slide table of a ring rolling mill.
CONSTITUTION: A pair of back-up rollers 70 are incorporated in each slide table 30 allowing rotation, and abutted to both side 63b of lower end back of a mandrel 63 lying at the advance end to receive reaction force from a work W0 acting on the mandrel 63. The back-up rolles are mounted to a bracket 75 with a pin 74 together with a bearing 71, a labyrinth collar 72 and a collar 73. The bracket 75 is placed on a check plate 76 fixed to the slide table 30 and fixed to the slide table 30 with a wedge 78 and a clamp rod 79. By this way, entrance of foreign matters between the mandrel 63 and each back-up roller 70 and coming down of the mandrel 63 can be prevented and accuracy of working can be raised.
TAKEBAYASHI KAZU
SAKAGUCHI KOUZOU
FUJITA NOBUYUKI
TOYOOKI KOGYO KK