Rolling mills having hydraulic forces exerted on the exterior roll surfaces

In a rolling mill having a frame and a plurality of rolls mounted thereon, means for exerting pressure on the exterior surface of at least one of said rolls which comprises at least one hydrostatic pressure device including a cylinder fixed with respect to said frame, a piston movable in said cylinder and defining a chamber therebetween, said piston having at one end a first surface area within said chamber and at the opposite end, a bearing surface facing said exterior surface of said roll, a plurality of hydrostatic pressure pockets formed in said bearing surface and a plurality of throttling ducts connecting said pockets individually with said chamber, and means for continuously applying fluid under pressure to said chamber and to said first piston surface area to force said piston toward said exterior roll surface and to supply fluid through said throttling ducts to said pockets so as to provide pressure fluid between said bearing surface and said exterior roll surface, the effective cross-sectional area of said bearing surface for producing forces between the bearing surface and the exterior surface of the roll being greater than the effective area of said first piston surface area exposed to pressure in said chamber so that the forces exerted by said fluid at both ends of said piston are such that said bearing surface and the surface of the roll are maintained in spaced apart relation during operation to permit a continuous fluid flow therebetween thereby avoiding direct contact between said piston and said roll and removing from said roll heat generated during said rolling operation.