The furnace models GF 75 - GF 1425 are particularly suitable for fusing of glass. Their special construction, with infrared heating elements mounted on the ceiling and light fiber insulation, ensures fast heat-up and cool-down rates and optimum fusing or slumping results. As protected infrared heating is used, any direct contact with the heating coils is avoided.

• Tmax 950 °C
• Heating elements in quartz glass tubes provided for short heat-up times and energy saving operation
• Overhead heating for direct heat transfer to your ware
• Table with brick insulation
• Hood insulation with special ceramic fibers for rapid heating and cooling
• Semiconductor relay provides for low-noise operation
• Fast power switching for precise temperature uniformity
• Type “K” (NiCr-Ni) thermocouple inside the furnace chamber for precise temperature measurement
• Housing made of high-grade stainless steel and ventilated lid
• Attractive and professional design enhances your image
• Gas springs counterbalance the lid weight for easy opening and closing
• Adjustable quick-release locks to secure the hood during firing
• Large “cool-touch” handle for opening and closing the furnace
• Angled sight ports with plugs let you see the progress of your work and cool quickly
• Delivered ready for operation including base frame with swivel casters and storage shelf
• Other sizes or custom designs available on request
• Exhaust air flap on hood for rapid cooling as additional equipment

The GFM series was developed to meet the special requirements of production. For different applications different table depths can be supplied. Standard tables have a depth of 65 mm for fusing. Various tables and tubs with different heights and numerous additional equipments are available as system add-ons. Especially economical is the alternating table system, in which one table is loaded while the other one is in the furnace (see page 23).

• Tmax 950 °C
• Infrared heated in hood which is atteched to stand
• Delivered with one table
• Table on wheels, freely movable, with brick insulation
• Heating elements in quartz glass tubes provided for short heat-up times and energy saving operation
• Lid heating elements for direct radiation on the surface of the glass
• Semiconductor relay provides for low-noise operation
• NiCr-Ni thermocouple inside the furnace for precise temperature measurement
• Insulation with special ceramic fibres for short heat-up and cool-down times
• Housing made from high-quality stainless steel and lid with ventilation ports (avoidance of rust formation during drying of plaster moulds)
• Attractive design and solid construction
• Gas dampers facilitate opening and closing of hood
• Adjustable locks for easy handling
• Large metal handle for opening and closing furnace
• Supply air and glass inspection ports with insulated doors, viewing window as an additional equipment

Additional equipment for fusing furnaces GF and GFM

• Electrically driven exhaust air dampers in the lid controlled via the extra function of the controller
• Automatic cover opening, programmable via the extra function of the controller for accelerated cooling from models GF 380 and GFM 380 upwards
• Cooling fan for accelerated cooling with closed lid
• Additional tables for extension of the furnace system
• Exchangeable table system for utilization of the residual heat of the furnace. Cycle times can be shortened by changing the tables in warm condition (depending on the ability of the respective glass to cope with temperature change)
• Air supply flap with window for observing the glass

Well-dimensioned quartz glass heaters provide for a very even temperature uniformity on the glass.

Sturdy design of brick insulation results in a solid flat table top.

Insulation of the table collar made of long lasting light-weight refractory bricks.

Solid state relays to switch the heating elements which results in an optimal adaptation of the firing cycle to the temperature curve.

Flaps with inspection glass as additional equipment for easy observation of the glass.

Large metal handle for opening and closing of the kiln.

Insulated gas dampers result for easy opening of the kiln.

Hood with exhaust air flap as additional equipment.

Base on castors with shelf for tools or other materials.

Automatically driven lid as additional equipment.

This furnace system is used for both fusing and for bending and slumping. It consists of an unheated table and a heated tub. The top-hat of the furnace is also heated. When the fusing table has been moved under the top-hat, heating is solely realized by means of the heating elements in the top-hat. If the tray has been moved under the top-hat it will be automatically connected and the furnace is heated from all six sides. In order to optimize the temperature uniformity during bending and slumping procedures, the heating will be controlled in three zones.

• Tmax 900 °C
• Heating from the top hat is realized with heating elements in quartz glass tubes for fusing
• Heating from all sides for bending/slumping
• Tub heating elements on support tubes for free heat radiation and a long lifetime
• SiC-plates provide for Level stack charging surface
• Bottom heating protected by SiC panels
• Insulation consists of fiber material with a special fastening
• Lightweight refractory bricks on the table provide for level stack charging surface
• Electro-hydraulic opening system of the top-hat with two-hand operation
• Single-zone control for fusing
• Three-zone control bending and slumping
• Exhaust air vents in the top-hat for accelerated cooling

Additional equipment

• Extension of the system with further tables/trays and a suitable rail system provides for the utilization of the residual energy under the top-hat and for saving time
• Electric drive of table and tub
• Customized dimensions
• Automatic exhaust air flaps activated via the furnace controls for faster cooling
• Controlled fan cooling with automatic exhaust air flaps for forced cooling

Nabertherm markets this range of top-hat furnaces for bending and slumping of large glass parts. The standard furnace is equipped with one table running on rails which can be pulled out for easy charging. As accessory an additional table can be integrated, which is charged while the other table is in the furnace. The furnace is heated from the ceiling and from the table.

• Tmax 900 °C
• Heating from lid and table
• 3-zone temperature control (lid-inner circular element, lid-outer circular element, table) for optimal temperature distribution
• Table heating can be switched-off for fusing
• Heating elements on supporting tubes provide for long service life
• Table heating elements covered by SiC tiles for level stacking support
• Hood insulated with high-quality fibre materials
• Table insulated with multiple layers of resistant, lightweight refractory bricks
• Top-hat to be opened by overhead crane in floor shop
• Protection guides for easy hood opening and closing
• Manually-operated vapour vent flaps
• Furnace table on fixed chassis for user-friendly charging height (800 mm)

Additional equipment

• Tailor-made furnaces in customized dimensions
• Hood side heating in case of high hood dimensions
• Interchangeable table system on rails, electrically powered on request
• Electro-hydraulically driven hood
• Cooling system
• Table on wheels for free movement
• Automatically driven vapour vent flaps