Abstract: A control method for crushing massive furnace slag using a swingable type crushing apparatus in which a crushing clearance is increased or decreased in a stepwise manner by a hydraulic mechanism depending on crushing conditions of the massive furnace slag, which may be blast furnace slag, convertor slag, and electric furnace slag. A hydraulic pressure of a hydraulic mechanism is detected as a variable of the crushing conditions and is compared with a set value so as to adjust the crushing clearance.

Abstract: A slag disposal method for disposing of slags produced in furnaces during iron or steel making processes comprises employing the steps of magnetic sorting of masses of crude slags of a size greater than a value ranging between 300 to 500 mm obtained from the furnaces into slags rich in iron (above about 50 to 60 percent) and slags not rich in iron (below about 50 to 60 percent) and then applying a compressive force to the slags rich in iron to cause a coarse crushing and/or deformation to reduce the size and at the same time increase the iron content due to the breaking and separation of the slags from the metal. Further magnetic sorting and sieving after griding are provided to obtain concentrates having high iron content and to improve recovery efficiency.

Abstract: A shell structure of a heavy-load type rod mill including a barrel having an outlet port and with a plate thickness of t.sub.1, and a pair of trunnions having journals integrally formed thereon and with a plate thickness of t.sub.2, which trunnions are welded to the barrel. At the weld joining the barrel and the trunnion, the relationship between the plate thickness t.sub.1 of the barrel and the plate thickness t.sub.2 of the trunnion is t.sub.1 .ltoreq.t.sub.2 .ltoreq.2t.sub.1.

Abstract: A liner for the outlet port of a rod mill including a cylindrical body provided on the peripheral edge of an opening of the liner and projecting outwardly through the outlet port to prevent a rod from exiting the liner. The projecting length of the cylindrical body on the side close to the end portion of the barrel of the rod mill is preferably longer than that on the opposite side.