JPS5791866A - Production of composite roll for rolling which is not constant in thickness of outside shell layer - Google Patents

Abstract

PURPOSE:To obtain a composite roll of which is not constant in the thickness of its outside shell layer in its axial center direction by changing the cooling ability of a barrel part chiller over the axial center direction in producing the composite roll by a coreless casting method. CONSTITUTION:For example, a circumferentially projecting surface A is formed on the outside circumferential surface of a barrel part chiller 1, and its wall thickness is changed toward the axial center direction. If sand molds 2, 3 for upper, lower journal parts are disposed to this and a solidified layer is formed by molten metal 4, an outside shell solidified layer 5 of the thickness changing over the axial center direction of A' in correspondence to the surface A on account of a difference in cooling ability is obtained. Thereafter, if the molten metal 4 in the layer 5 is substituted with another molten metal for a core material at a suitable timing, the composite roll wherein the layer 5 and the core material 6 are melt-stuck to one piece is obtained. The cooling capacity of the chiller is made variably adjustable, too, by the local cooling of the chiller or with the kinds of the mold coating material on its inside surface and the thicknesses of the mold coating material.