Batch furnace assembly for processing wafers, comprising a process chamber housing defining a process chamber and having a process chamber opening, a wafer boat housing defining a water boat chamber, a door assembly, a differential pressure sensor, and a controller. The door assembly has a closed position in which it closes off the process chamber opening. The door assembly defines in a closed position a door assembly chamber having a purge gas inlet for supplying purge gas to the door assembly chamber for gas sealingly separating the process chamber from the wafer boat chamber. The differential pressure sensor assembly fluidly connects to the door assembly chamber and is configured to determine a pressure difference between a pressure in the door assembly chamber and a reference pressure in a reference pressure chamber. The controller is configured to establish whether the pressure difference is in a desired pressure range.

Batch furnace assembly for processing wafers, comprising a process chamber housing defining a process chamber and having a process chamber opening, a wafer boat housing defining a water boat chamber, a door assembly, a differential pressure sensor, and a controller. The door assembly has a closed position in which it closes off the process chamber opening. The door assembly defines in a closed position a door assembly chamber having a purge gas inlet for supplying purge gas to the door assembly chamber for gas sealingly separating the process chamber from the wafer boat chamber. The differential pressure sensor assembly fluidly connects to the door assembly chamber and is configured to determine a pressure difference between a pressure in the door assembly chamber and a reference pressure in a reference pressure chamber. The controller is configured to establish whether the pressure difference is in a desired pressure range.

The invention relates to a dental furnace, in particular a high-temperature dental furnace for oxide ceramics such as zirconium dioxide with sintering temperatures of between 1350 C. and 1650 C., having heating elements (14, 16) which are intended to give off heating energy to a firing chamber (12) in the dental furnace (10). The heating elements (14, 16) are configured as electrical resistance heating elements and supported below the firing chamber (12) each by means of at least one heating element support foot (18). The heating elements (14, 16) extend vertically to the top starting from the heating element support feet (18) and at the top, end in an arch (46), in particular in a semicircular arch or possibly in a pointed arch, without an upper lateral support, in particular not in the region of the arch (46).

The invention relates to a dental furnace, in particular a high-temperature dental furnace for oxide ceramics such as zirconium dioxide with sintering temperatures of between 1350 C. and 1650 C., having heating elements (14, 16) which are intended to give off heating energy to a firing chamber (12) in the dental furnace (10). The heating elements (14, 16) are configured as electrical resistance heating elements and supported below the firing chamber (12) each by means of at least one heating element support foot (18). The heating elements (14, 16) extend vertically to the top starting from the heating element support feet (18) and at the top, end in an arch (46), in particular in a semicircular arch or possibly in a pointed arch, without an upper lateral support, in particular not in the region of the arch (46).

An optical fiber draw furnace muffle includes a body portion defining a substantially cylindrical cavity extending along a centerline axis of the muffle. A tapered portion has an interior surface which defines a first curved portion with a first radius of curvature and a second curved portion with a second radius of curvature. At least one of the first and second radii of curvature has a radius greater than a radius of the cylindrical cavity.

An optical fiber draw furnace muffle includes a body portion defining a substantially cylindrical cavity extending along a centerline axis of the muffle. A tapered portion has an interior surface which defines a first curved portion with a first radius of curvature and a second curved portion with a second radius of curvature. At least one of the first and second radii of curvature has a radius greater than a radius of the cylindrical cavity.

Described herein are glass forming apparatuses with cooled muffle assemblies and methods for using the same to form glass ribbons. According to one embodiment, a muffle assembly for a fusion forming apparatus may include a muffle frame comprising a back wall, a front wall opposite the back wall, and a pair of sidewalls joining the front wall to the back wall in a closed-loop. At least one first cooling tube may extend through the back wall and the front wall across the closed-loop. At least one second cooling tube may extend through the back wall and the front wall across the closed loop such that the at least one second cooling tube is spaced apart from and parallel with the at least one first cooling tube.

Described herein are glass forming apparatuses with cooled muffle assemblies and methods for using the same to form glass ribbons. According to one embodiment, a muffle assembly for a fusion forming apparatus may include a muffle frame comprising a back wall, a front wall opposite the back wall, and a pair of sidewalls joining the front wall to the back wall in a closed-loop. At least one first cooling tube may extend through the back wall and the front wall across the closed-loop. At least one second cooling tube may extend through the back wall and the front wall across the closed loop such that the at least one second cooling tube is spaced apart from and parallel with the at least one first cooling tube.

A furnace muffle for an annealing furnace, the furnace muffle including a base body arranged to delimit a volume to be heated, at least one actuator connected to the base body in such a manner that the actuator, during the operation of the furnace muffle, can exert a force on the base body, at least one sensor arranged to detect a force exerted by the base body during the heating or cooling and/or a change in a length of the base body during the heating or cooling, and a control device connected to the actuator and the sensor, which is arranged so that during the operation of the furnace muffle, it controls the force exerted on the base body as a function of the force or change in length detected by the sensor.

A furnace muffle for an annealing furnace, the furnace muffle including a base body arranged to delimit a volume to be heated, at least one actuator connected to the base body in such a manner that the actuator, during the operation of the furnace muffle, can exert a force on the base body, at least one sensor arranged to detect a force exerted by the base body during the heating or cooling and/or a change in a length of the base body during the heating or cooling, and a control device connected to the actuator and the sensor, which is arranged so that during the operation of the furnace muffle, it controls the force exerted on the base body as a function of the force or change in length detected by the sensor.