Dimensionally stable movable furnace hearth

Abstract

An upper furnace portion (A) includes side walls (12, 14) extending along its lower edge. A dimensionally stable furnace hearth (B) is movably mounted adjacent the furnace lower edge and is displaced a small distance from the side walls, such that the hearth is movable without engaging the side walls, yet sufficiently close that relatively little heat tends to pass between the hearth and the side walls. The hearth includes a metal base plate (20) to which a plurality of vertically extending anchoring plates (26) are connected and supported by gussets (30). A plurality of wires (28) are welded to the anchoring plates and extend into peripheral refractory elements (24) which are integrally molded to the wires and the anchoring plates. A plurality of refractory slabs (34) and bricks (36) are supported by the base plate and are disposed within an area defined by the peripheral refractory elements to define a workpiece supporting surface. A plurality of expansion joints (32) permit the peripheral refractory elements to be constrained against outward or radial movement, and a plurality of expansion joints (32 ) accommodate circumferential or longitudinal expansion. Further expansion joints (38, 40) extend within the peripheral refractory elements and through the refractory slabs and bricks (34, 36) to permit thermal expansion thereof.

Dependencies are inferred from the claim text.