Abstract: Steel tubulars are deposited into an insulated container shortly after the steel tubulars are formed in a seamless hot rolling machine. The tubulars are covered by an insulating blanket and allowed to cool at a selected rate to form desired microstructure in the steel of the tubulars. No external energy supply or controls are necessary to achieve the desired microstructure. The side walls of the container taper outwardly and are made of a sandwiched structure, having spaced apart sheet metal members with a layer of insulation there between. The end walls are similarly constructed. The bottom of the container is lined with granular insulating material to cushion the shock of the tubulars being dropped into the container and to insulate the bottom of the container. Stainless steel mesh is used as a sling and embraces the tubulars to facilitate removing the tubulars from the container after the desired amount of cooling.

Abstract: Steel tubulars are deposited into an insulated container shortly after the steel tubulars are formed in a seamless hot rolling machine. The tubulars are covered by an insulating blanket and allowed to cool at a selected rate to form desired microstructure in the steel of the tubulars. No external energy supply or controls are necessary to achieve the desired microstructure. The side walls of the container taper outwardly and are made of a sandwiched structure, having spaced apart sheet metal members with a layer of insulation there between. The end walls are similarly constructed. The bottom of the container is lined with granular insulating material to cushion the shock of the tubulars being dropped into the container and to insulate the bottom of the container. Stainless steel mesh is used as a sling and embraces the tubulars to facilitate removing the tubulars from the container after the desired amount of cooling.