A long ceramic body with less fluctuation of shape accuracy, and with higher shape accuracy, is produced by controlling the deformation of the long ceramic body. The long ceramic body is formed by firing a long non-sintered ceramic body (5), when the long body (5) is suspended in a sheath so as not to contact directly the interior surface of the sheath, at a temperature at which sintering can take place, until sintering is completed. Then the long body is turned upside down and re-fired at a temperature at which sintering can take place. A predetermined downward load (10) is applied to the long body at the vicinity of the bottom thereof during second firing.

An apparatus for charging raw sinter mix to a sintering machine comprises:

   supply mechanism for supplying raw sinter mix onto a pallet;

   a screen-shaped chute for charging the raw sinter mix supplied from the supply means onto the pallet;

   the screen-shaped chute comprising:

• a plurality of screen constituting member groups; and
• a plurality of guide members to guide the screen constituting members,
  
  

Zum gleichmäßigen, querkraftarmen Belasten von Keramikplattenstapeln beim Sintern in Sinteröfen, wobei die Belastung über eine Traverse erfolgt, wird zwischen Stapel und Traverse eine Druckplatte eingefügt. Diese Druckplatte besteht aus einer oberen Druckplatte und einer unteren Druckplatte, wobei mindestens eine der Druckplatten knicksteife Wangen mit Aufhängungen trägt und zwischen den Aufhängungen der einen Druckplatte und der anderen Druckplatte bzw. deren Aufhängungen biegsame Verbindungselemente angebracht sind.

An apparatus for charging material to be sintered into a sintering machine comprises a shuttle conveyer (12) transporting pelletized material to be sintered, a wide conveyer (13) receiving said pelletized material from the shuttle conveyer and feeding the pelletized material to a pallet (14) moving in a predetermined direction, a deflector plate (15) receiving the pelletized material from the wide conveyer and feeding the pelletized material to the pallet and a support plate (16) supporting the material fed to the pallet from behind, the support plate being arranged facing the deflector plate below the wide conveyer and over the upper side of the pallet.

An improved process for sintering extruded powder shapes comprising drying or calcining an extruded shape in a microwave furnace and rapid sintering the shape in a plasma fired furnace. Alternatively, calcining or drying may take place within a furnace heated by the plasma furnace's exhaust. The process of the invention is especially useful for silicon carbide extruded materials and for tubular shapes. This process significantly reduces sintering times and costs. Use of the process yields a high strength sintered product.

An improved process for sintering extruded powder shapes comprising drying or calcining an extruded shape in a microwave furnace and rapid sintering the shape in a plasma fired furnace. Alternatively, calcining or drying may take place within a furnace heated by the plasma furnace's exhaust. The process of the invention is especially useful for silicon carbide extruded materials and for tubular shapes. This process significantly reduces sintering times and costs. Use of the process yields a high strength sintered product.

A problem that can occur with a large rotary kiln assembly is that it can move out of position or seals can become defective, making an escape of materials possible. The present invention provides transducers (10, 15) for detecting movement of the rotary kiln itself or part of a seal assembly secured thereto relative to an inlet/outlet arrangement of the kiln assembly or a part of a seal arrangement secured thereto and also means whereby the condition of the seals can be monitored by following changes in the pressure or flow rate of a purge gas. If the rotary kiln (2) should move out of alignment, then corrective action can be taken. If the seals should leak, then they are changed. A record of kiln movement is provided and if movement is excessive, an alarm (20) is sounded.