RING ROLLING MILL

A ring rolling mill has a pair of radial rolls acting on a workpiece ring by engaging radially opposite peripheries thereof, and a pair of axial rolls, which are preferably truncated conical rolls, acting axially on the ring by engaging axially opposite end surfaces thereof. The two rolls of each pair are adjustable toward each other and at least one roll of each pair is driven by associated adjustable speed driving means. One driving means is adjustable to a preselected nominal peripheral speed of the roll driven thereby, and a control adjusts the other driving means to set the peripheral speed of the roll driven thereby in accordance with the peripheral speed of the roll driven by the one driving means. Sensors engageable with the ring detect power transmission, through the ring, between the two driving means, and a second control is operable, responsive to detection of such power transmission by the sensors, to restore the peripheral speeds of the driven rolls into accordance with each other.