Roller reinforced with a hard metal jacket

Claim 1

In a hot roller for working material, which roller includes a rotatably mounted roller body, a reinforcing working jacket composed of hard metal and having the form of a hollow cylinder disposed around the roller body, clamping means mounted between the roller body and the jacket and including clamping rings bearing against the axial end surfaces of the jacket and means acting via the rings for applying an axial compressive prestress force to the jacket, the axial end surfaces of the jacket and the clamping ring surfaces which bear thereagainst being inclined with respect to the roller axis, and the roller body and working jacket defining an annular gap between the inner peripheral surface of the working jacket and the outer peripheral surface of the roller body, the dimension of the annular gap in the direction between said jacket and roller body being sufficiently large to maintain the outer peripheral surface of the roller body and the inner peripheral surface of the working jacket out of contact with one another during operation of the roller at temperatures extending over its entire operating temperature range, the improvement wherein the clamping surfaces at opposed ends of said working jacket diverge from one another in the radial direction away from the roller axis.