Patent ID: 7919041
Filing Date: 2011-04-05
Classification: C21D

Abstract:
1. A hearth roll apparatus for an annealing furnace comprising: a ceramic tube which is provided inside the annealing furnace to contactingly feed a strip sheet; a roll shaft which is coupled to a first end of the ceramic tube and extends across the annealing furnace through the ceramic tube; a tube fixing sleeve which is coupled to a second end of the ceramic tube and through which a portion of the roll shaft is inserted; and a tension generating unit which interlocks with the roll shaft and the tube fixing sleeve and supplies a tensile force for stretching the roll shaft in a longitudinal direction, wherein the roll shaft is formed with multiple step portions in the longitudinal direction and the tube fixing sleeve is formed with multiple step portions in the longitudinal direction, the multiple step portions of the roll shaft being disposed inside thereof.