The HT 04/16 ff. high-temperature furnaces are the ideal choice for sintering special glass, e.g. quartz glass or for melting trials in the laboratory. Excellent temperature uniformity, solid construction provide for the necessary competitive edge with resprect to quality.

Standard version, electrically heated (for gas heating, see page 31)

• Tmax 1600 °C, 1750 °C, or 1800 °C
• Furnace sizes from 4 to 450 liters
• High-quality molybdenum disilicide (MoSi2) heating elements
• Parallel swivel door, chain-guided, enabling safe opening and closing without damage to the fibre insulation in the collar area, protection of user from radiation from the furnace
• Door labyrinth sealing provides for optimum energy efficiency and temperature distribution
• Door area amored with stainless steel to avoid burn damages
• Reinforced floor as protection for bottom insulation as standard from models HT 32/16 upwards
• Over-temperature limit controller for product and furnace protection
• Furnace chamber lined with first-class, durable fibre material
• Special ceiling construction with high durability
• Long-lasting thermocouple, PtRh-Pt, Type B or Type S
• Vapor vent in the furnace roof
• For control system see page 42

Besides our extensive line of electrically heated high-temperature chamber furnaces, we can also offer gas-heated models, customized to your application. Please contact us.

Additional Features

• Cooling fan For cycle time acceleration furnace sized specific fans are installed. The fan speed is preselected per segment. The controller is automatically switched on and off. Hence, different speeds can be applied e.g. for binder removal or cooling. With HiProSystems-Controllers, lenear cooling is possible.
• Air preheating Air preheating can also be used with our high-temperature furnaces. This allows the furnace to be used as a combi furnace for debinding and sintering in a single process.
• Start-up circuit A special circuit in the switchgear eliminates the problem of heating too fast when below 250 °C, typical for molybdenum disilicide heating elements, is eliminated. This feature is particularly recommended when firing ceramics which need sensitive handling in this temperature range.
• Automatic control of vapor vent flaps
• Customized furnace dimensions
• Stainless steel exhaust gas hoods
• Catalytic or thermal afterburners
• Kiln furniture
• Process documentation using temperature plotter or PC software
• Protective gas inlet and outlet, e.g. for reduction of oxygen content in exothermic debinding

The HFL 16/16 - HFL 160/17 series is particularly characterized by their special cladding with light refractory bricks. This insulation is necessary when aggressive gasses (such as vapourized glass) or acids may be produced in the process.

• High-quality molybdenum disilicide (MoSi2) heating elements
• Insulation with light refractory bricks and special backup insulation
• Type B thermocouple
• Furnace sizes of 16 to 160 liters
• For the release of vapours, a 30 mm large exhaust hole is integrated into the roof of the furnace
• Over-temperature limit controller for protection of material
• For control system see page 42

Optional equipment

• Exhaust air flap controlled manually or automatically for better ventilation of furnace chamber
• Fan for better ventilation of combustion chamber and for fast cooling of the furnace
• Protective gas connector and seal of furnace casing to allow flushing of furnace with protective gasses
• Manual or automatic gas supply system

In the production of small special glass components, e.g. glass filters or quartz glass bulbs, the transfer from the debindering furnace to the sintering furnace is often associated with many disadvantages and risks. The goods cannot be allowed to cool in between the processes, and the re-loading of the debindered parts leads to an incalculable quantity of rejected goods.

Since an optimum temperature distribution is a requirement in the lower temperature range the furnace has a preheating system. Blowing in the warm, separately controlled air ensures an optimum temperature distribution with the help of the controlled air swirl. During the debindering process, the vapour vent flap of the furnace is open so that the waste air can be immediately directed out of the furnace.

Through perforated ceramic pipes in the chamber the preheated air is very evenly blown horizontally in different layers into the furnace chamber. The heating zones of the furnace and the air preheating system are controlled separately but operate jointly up to about 500 °C. Subsequently, the air preheating switches off and the furnace continues the sintering process without having to cool down in between.

Standard Version N 200/HDB + N 300/HDB

• Tmax 1340 °C
• Horizontal blowing-in of preheated air up to max. 500 °C, continuation of the process up to the sintering temperature with 5-side heating in the furnace
• Bottom heating covered by SiC heat-conducting plate (level stacking support)
• Automatic control of vapour vent flaps
• Separate outlets for exhaust and cooling air
• Exhaust hood in stainless steel 1.4301
• Two-zone control, preheating of air inflows also controlled separately as a second heating source
• Temperature distribution better than DT < 14 K during the debinding process and better than DT < 20 K [according to DIN 17052-1] during the dwell time when sintering
• Safety matrix to protect furnace and charge in case of disturbance or break-down
• For control system see page 42

Additional Features

• Customer-specific versions with respect to temperature and size
• Multi-zone control for processes requiring optimum temperature distribution
• Cooling fan to shorten process cycle
• Scales for measuring the weight loss during firing
• Thermal or catalytic afterburning systems

The LH 15/12 - LF 120/14 laboratory furnaces have been trusted for many years as professional chamber furnaces for the laboratory. These furnaces are available with either a robust insulation of light refractory bricks (LH models) or with a combination insulation of refractory bricks in the corners and low heat storage, quickly cooling fibre material (LF models). With a wide variety of optional equipment, these models can be optimally adapted to your processes.

• Tmax 1200 °C, 1300 °C or 1400 °C
• 5-sided heating for very good temperature uniformity
• Heating elements on support tubes ensure free heat radiation and a long service life
• Protection of floor heating and flat stacking surface provided by embedded SiC plate in the floor
• LH models: multilayered, fibre-free insulation of light refractory bricks and special backup insulation
• LF models: high-quality fibre insulation with corner bricks for shorter heating and cooling times
• Door with brick-on-brick seal, hand fitted
• Short heating times due to high installed power
• Side vent with bypass connection for exhaust pipe
• Self-supporting arch for high stability and greatest possible protection against dust
• Quick lock on door
• Freely adjustable air slide intake in furnace floor
• Stand included
• For control system see page 42

Additional Features

• Parallel swinging door, pivots away from operator, for opening when hot
• Separate wall-mounting or floor standing cabinet for switchgear
• Automatic vent flap
• Cooling fan for shorter cycle times
• Protective gas connector, sealed casing
• Manual or automatic gas supply system

This kiln was designed to test different types of glass plates such as fire protection glass. In addition to the kiln door, there is a second frame which can be swung in front of the inner chamber into which the test plate is placed. This door is fixed with a special mechanism. The kiln chamber is flat and is heated by element coils supported on ceramic tubes mounted only on the back wall so that the heat radiates directly onto the glass surface. The kiln achieves exceptionally short cycle times due to the very small chamber volume and high power input.

These powerful laboratory bench-type furnaces are available for maximum temperatures from 1400 up to 1800 °C. The HTC series is suitable for temperatures up to 1600 °C. We recommend the LHT series for working temperatures above 1550 °C up to 1800 °C.

HTC 03/14 - HTC 08/16

• Tmax 1400 °C, 1500 °C oder 1600 °C
• Double-wall housing with fan cooling for low external temperatures and high stability
• Vapor vent in rear wall
• High-quality fibre material, in reconcilation with the working temperature
• SiC rod-heating
• Easy handling of the heating element
• Flap-down door usable for temporary storing of charge
• For control system see page 42

Additional Features LHT 02/16 - LHT 08/18

• Tmax 1600 °C, 1750 °C oder 1800 °C
• Molybdenum disilicide heating elements used as heat source
• Parallel swinging door, opening upwards
• For control system see page 42