PURPOSE: To make a sizer which is used for manufacturing a seamless steel tube so that it can be used for both of 2-roll and 3-roll sizers while screw down device and driving system are used in common.
CONSTITUTION: A housing 11 for 3-roll whose external size is same as an inner frame 3 for 2-roll is formed so as to be attachable to a housing 2 symmetrically on front and rear sides and symmetrically on upper and lower sides in the direction of the line and a 3-roll stand is constituted by arranging a pair of three rolls 12-14 in this 3-roll housing 11 in such a manner that the direction that is orthogonally crossed with the axis 15 of rotation of roll is crossed to the vertical line L in a plane that is vertical to the direction of the line of one roll 12 of these three rolls. In this way, by using the frame 1, housing 2, screw down device 7, driving systems 5, 6, etc., of each stand in common, the sizer 10 which is used for both a 2-roll stand or 3-roll stand can arbitrarily select one of the two stands and advantages of both stands are obtd.
AKITA SHINJI
SAKURA HIROMOCHI
OKAMOTO YOSHIHIDE
NIPPON KOKAN KK