High temperature melting furnace

A high temperature melting furnace comprising a fibrous refractory vertical cylindrical shell, a fibrous refractory circular furnace top resting on the upper end of the shell, a plurality of molybdenum disilicide resistance wire loops depending inside the shell from right-angle molybdenum disilicide terminals which extend radially through the shell and hold the loops spaced from the inside of the shell, means for mounting the terminals on the shell so as to prevent concentrations of the terminals' weight on the shell, the furnace top having a vertical access hole provided with a fibrous refractory closure plug which is upwardly removable to permit access to the inside of the shell when the furnace is operating, a fibrous refractory furnace bottom on which the shell rests and the furnace bottom having a vertical charging hole provided with a refractory pedestal removably insertable in the charging hole and adapted to support a crucible for upward insertion into the furnace, the upper end of the shell being formed with internal recessed upper and lower annular shelves respectively of larger and smaller diameters and a small fibrous refractory disk resting on the smaller diameter shelf and a larger fibrous refractory disk resting on the larger diameter shelf and on top of the small disk, both of the disks being radially split with their respective slits circumferentially offset from each other and the disks having holes registered with the top's access hole and through which the access closure plug extends, the furnace top resting on the larger disk and the disks supporting the weight of the furnace top, said shell furnace bottom and furnace top being free from rigid horizontal and vertical restraint to thermal expansion and contraction and said split larger and smaller disks being free from rigid connection with each other and the shell, the outside of the shell having access to the ambient air and said fibrous refractory comprising interlocked refractory ceramic fibers.