Top Loading Furnaces

Top loading furnaces are ideal for tempering quartz glass. With smaller components, the furnaces are filled manually from the top and, with larger or heavier components, they are filled with the help of an indoor crane. With their adapted heating and the special arrangement of the heating elements, the furnaces ensure good temperature uniformity. With an extensive range of additional equipment, top loading furnaces can be adapted to suit many different process requirements. 

• Tmax 900 °C or 1240 °C
• Three or five-sided heating for optimum temperature uniformity
• Heating elements on carrier tubes ensure free heat radiation and a long service life
• Multi-layer refractory insulation and special rear insulation
• Exclusive use of insulation materials without categorization according to EC Regulation No 1272/2008 (CLP). This explicitly means that alumino silicate wool, also known as “refractory ceramic fiber” (RCF), which is classified and possibly carcinogenic, is not used.
• Bottom heating protected by SiC tiles with an even stacking base
• Fiber insulation in the lid
• Lids are opened and closed with various standardized solutions
• Over-temperature limiter with adjustable cutout temperature as temperature limiter to protect the furnace and charge
• Over-temperature limiter with adjustable cutout temperature  as temperature limiter to protect the oven and load
• Defined application within the constraints of the operating instructions
• Controller C540 (10 programs with each 20 segments)

• Manual fresh air opening in lower area of the top loading furnace
• Manual exhaust air opening in the lid
• Automatic exhaust air flap for faster cooling
• Cooling system to speed up furnace cooling with a fan and specified temperature gradients or a fixed volume of fresh air. Both operating modes can be activated for different segments, using an extra function of the controller.
• Multiple-zone control of the heating to optimize temperature uniformity
• Fabric cover to reduce fiber dust
• Split lid to divide the furnace chamber into two halves
• Special solutions with customer-specific dimensions and equipment options are available
• Process control and documentation via VCD software package or Nabertherm Control Center (NCC) for monitoring, documentation and control