Kameroven, grafiet isolatie - HTK GR

1. Frame
2. Water cooled vessel
3. Heating cassette
4. Groove for the sealing
5. Front door
6. Graphite insulation

Inside the chamber, heating elements are positioned at the bottom, left, right, and top sides of the furnace chamber allowing for improved temperature uniformity. For larger volumes, the back wall and front are equipped with heating elements to maintain excellent temperature uniformity. The HTK W, HTK MO, HTK GR and HTK KE furnaces are surrounded by a water cooled vessel; thus classifying, the HTK systems as a cold wall furnace. The cooling water is guided through the double walled vessel.

Upon request, the HTK GR can be operated up to 3000 °C. For operation at 3000 °C, the furnace is specially designed with a specific isolation thickness, optimal positioning of the heating elements, and a pyrometer for temperature measurement and control. The pyrometer directly measures the heat radiation by optical methods via a window inside the furnace and is not directly inserted into the furnace.

This measurement principle only works if a sufficient amount of radiation is emitted. The needed radiation is only generated at temperatures exceeding 400 °C. For lower temperatures, a sliding thermocouple is used to control the lower temperatures.

Because of the increasing vapor pressure of graphite, 3000 °C operation is only possible under inert gas atmosphere. Additionally, the high vapor pressure also results in carbon being released to the atmosphere. For carbon sensitive samples, a metallic high temperature furnace must be used.