Abstract: Hot steel slabs are cooled in upright, edge-on state between respective pairs of adjacent cooling walls, each of which comprises a row of intercommunicating boiler tubes conducting cooling water and constituting one component of a circulatory heat recovery system. As the slabs cool, heat is transferred therefrom principally by radiation to the cooling walls, in which the cooling water is turned into a mixture of steam and hot water. A slab handling system comprising roller conveyers, slab uprighting and tilting devices, and a tong crane for picking up and lowering slabs is provided.

Abstract: Apparatus for regulated cooling of hot objects by liquid medium or media in which the cooling is varied by varying the pressure under which the cooling takes place. The apparatus comprises an open or closed container for the cooling agent or agents having means for regulating the temperature of the cooling agent, means for stirring the cooling agent, means for conveying the cooling agent to a shaft-constituting part of the container, means for inserting the object into the shaft and means for regulating the pressure of the cooling agent in said shaft.

Abstract: A metal cooling wall surrounds a conveyor carrying solids such as steel slabs at high temperature through the chamber defined by the cooling wall and the wall receives heat from the slabs by radiation. A liquid such as water flowing under pressure within passages within the cooling wall removes heat from the cooling wall with the control of coolant temperature controlling the cooling speed of the solids. A gas such as water vapor or carbon dioxide gas having the absorbing ability of the radiation fills the space between the slabs and the cooling wall to further control the cooling speed of the steel billets.