The invention relates to a furnace for the treatment of material, in particular for the oxidative treatment of fiber material, in particular for producing carbon fibers, comprising a housing (12) having a housing inner space (14), which is gas-tight with the exception of passage areas (18, 20) for the fibers (22). In the housing inner space (14) of the housing (12), a process chamber (28) is located. A hot working atmosphere (40) can be generated by means of an atmosphere device (42). The atmosphere device (42) comprises a flow system (46) having flow channels (48), which are arranged in the housing inner space (14) each defining one flow chamber (50), and are provided with flow passages such that the respective flow chambers (50) are fluidically connected to the process chamber (28) in such a way that hot working atmosphere (40) can be delivered to the process chamber (28) in at least one main flow direction (44) and can be discharged from the process chamber (28). A revision system (72) is provided, through which flow chambers (50) of flow channels (48) are accessible through the housing (12).

A mobile removable hearth skid for a furnace and/or cooling chamber including: a base, the base including a top horizontal surface supporting a refractory platform which possesses a perimeter edge including a front perimeter edge, a rear perimeter edge, and at least two side perimeter edges. The rear perimeter edge and the at least two side perimeter edges form a continuous shoulder extending beyond the base perimeter edge. Also disclosed is a furnace and/or cooling chamber including a refractory lining with a continuous ledge at the bottom edges of the refractory linings mounted on the rear wall and the at least two side walls. A gap is formed by the furnace supports between a bottom surface of the ledge and a surface supporting the furnace supports. The shoulder and ledge form a removable refractory seal.

A furnace door sealing device for a low-pressure diffusion furnace is provided. The furnace door sealing device includes a furnace door, a fixed shaft and a fixed base which are coaxially arranged in sequence from front to back. A bearing pedestal is fixed at the center of the rear end surface of the furnace door. A centripetal knuckle bearing is arranged in the bearing pedestal. An outer ring of the centripetal knuckle bearing is fixed in the bearing pedestal. An inner ring of the centripetal knuckle bearing fixedly sleeves the front end of the fixed shaft. The rear end of the fixed shaft is fixed in the fixed base. A supporting plate is also fixed on the front end surface of the fixed base. Multiple spring adjusting assemblies are arranged on the supporting plate at an interval.

An efficient method of installing an access door in a high temperature structure having an outer door casing spaced from an inner door liner, wherein the casing and liner are aligned to thereby define a passageway through a wall of the structure. The space between the casing, the liner and the structure wall is filled with compressed insulation, and this filled space is temporarily closed off with liner insert plates which thereby compress the insulation and provide a temporary door casing frame. The replacement prehung door assembly is installed in this surrounding temporary door casing frame, and the doorframe assembly is secured to the inner door liner, and thereafter the temporary insert plates closing off the space between the door casing and door liner are removed thereby permitting the compressed insulation in the space between the casing and the liner to expand and engage the doorframe assembly.

A concrete products curing kiln and kiln closure apparatus comprising a pressure door shaped to cover an opening of the kiln, and an expandable chamber. The expandable chamber is positioned such that inflation of the chamber causes the chamber to expand and press on, and at least partially seal, the pressure door against a kiln door frame defining the kiln opening.