HTBL bottom loading graphite furnaces offer temperatures of 2200 °C or 3000 °C upon request. Graphite models of the HTBL are offered in volumes of 50, 80 and 200 litres.
One clear advantage is the easy loading and unloading of the HTBL type furnaces. Once the hearth has been lowered, the sample is accessible from all sides without limitations. Sample loading is extremely easy and user-friendly, especially with delicate samples. Additionally, sample thermocouples can placed at specified locations within the chamber. A retort may also be used with the HTBL. The movement of the loading area is fully automated and driven by a hydraulic arm. Once the loading area has reached the lowest position, the user can manually rotate the loading platform outward by 90 °.
Nitrogen, Argon, and Hydrogen gases are available for use as either pure or mixed gas. Other gases may be installed upon request. A slight overpressure or controlled partial pressure, to establish a defined gas flow, can be used in the furnace. Operation with air is not possible.
Various dosing and controlling devices control all gases. Depending on the vacuum requirements, vacuum pumps are configured specifically for the application or as requested. The temperature is independently controlled to achieve the best uniformity.
Application Examples
annealing, brazing, carbonisation, ceramic injection moulding (CIM), debinding, degassing, drying, hardening, metal injection moulding (MIM), pyrolysis, quenching, rapid prototyping, siliconization, sintering, soldering, sublimation, synthesis, tempering
Standard features
- Graphite furnaces offer the highest possible temperatures
- Hydrogen partial pressure operation upon request
- Precisely controlled vacuum pumping speeds appropriate for use with powders
- Fully automatic operation
- Data recording for quality management
Bottom loading furnace, graphite insulation - HTBL GR View inside of the HTBL GR
- heating elements
- water cooled current
- bottom locking device
- frame
- bottom plate
To load and unload the furnace, locking clamps are manually operated. Vacuum tubes must also be be attached and detached manually. Aside from these two steps, all remaining movements of the furnace hearth are fully automated. After the bottom, loading area has reached the lowest position, the user can rotate the platform outward by 90°. The automated features of the HTBL are ideal for large scale production.
The graphite based HTBL is equipped with a pyrometer and a sliding thermocouple. A retort can be supplied on request. Graphite is a very versatile construction material for high temperature furnaces. However, if the sample is sensitive to carbon, a metallic furnace must be used.
View inside HTBL GR
Bottom loading furnace, graphite insulation - HTBL GR Technical Data
| Insulation material | Dimensions: External H x W x D (mm) | Transport weight (kg) | Usable space | Volume (l) | Ø x H, usable space without retort (mm) | Ø x H, usable space with retort (mm) | Thermal values | Tmax vacuum (°C) | Tmax atmospheric pressure (°C) | -Delta-T, between 500°C and 2200°C (K) according to DIN 17052 | Max. heat-up rate (K/min) | Cooling time (h) | Connecting values | Power (kW) | Voltage (V) | Current (A) | Series fuse (A) | Vacuum (option) | Leakage rate - clean, cold and empty (mbar l/s) | Vacuum range depending on the pumping unit | Cooling water required | Flow (l/min) | Gas supply | Nitrogen or Argon flow, others on request (l/h) | Controller | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| HTBL-H 50 GR/22-1G | Graphite | 4300 x 2400 x 2200 | 3200 | |
50 | 300 x 700 | 280 x 680 | |
2200 | 2200 | ± 10 | 10 | 8 | |
120 | 400 (3P) | 3 x 175 | 3 x 250 | |
< 5x10-3 | rough or fine vacuum | |
100 | |
500-2000 | Siemens WinCC flex |
| HTBL 50 GR/22-1G | Graphite | 3500 x 2400 x 2200 | 3200 | |
50 | 400 x 400 | 380 x 380 | |
2200 | 2200 | ± 10 | 10 | 8 | |
120 | 400 (3P) | 3 x 175 | 3 x 250 | |
< 5x10-3 | rough or fine vacuum | |
100 | |
500-2000 | Siemens |
| HTBL 80 GR/22-1G | Graphite | 4300 x 2400 x 2200 | 3500 | |
80 | 400 x 700 | 380 x 680 | |
2200 | 2200 | ± 10 | 10 | 12 | |
200 | 400 (3P) | 3 x 290 | 3 x 400 | |
< 5x10-3 | rough or fine vacuum | |
150 | |
500-2000 | Siemens |
| HTBL 200 GR/22-1G | Graphite | 4800 x 2400 x 2600 | 4200 | |
200 | 500 x 900 | 480 x 880 | |
2200 | 2200 | ± 10 | 10 | 16 | |
300 | 400 (3P) | 3 x 430 | 3 x 630 | |
< 5x10-3 | rough or fine vacuum | |
220 | |
500-2000 | Siemens |
Bottom loading furnace, graphite insulation - HTBL GR Downloads
Heat treatment at low pressures
High temperature vacuum furnaces are used for heat treatment of samples at low pressure (down to 10-6 mbar) and under partial gas atmospheres. In the bottom loader version the bottom is lowered and driven out of the furnace. It then pivots forward to permit easy loading. This design makes the useable volume accessible from all sides and allows for exact placement of the sample thermocouples which measure the temperature of the sample.