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Gradient Furnace 1600C

The Orton GTF-MD-16 Series (1600°C maximum) Furnace is a specially designed horizontal tube furnaces with controlled, reproducible, linear thermal gradients of approximately 10-12°C per inch. Available in 12" and 16" monitored zones with 1600°C maximum firing temperature. Thermocouples on 2" centers monitor the temperatures along the gradient zone, so the temperature of the material at any position along the Sample D-tube hearth is known. Visual or post firing analyses of sections taken from the fired material at any position can be measured, recorded, and studied as a function of temperature.

The furnace is a rectangular, metal shell structure that houses the refractory fiber insulation and four molybdenum disilicide heating elements that surround one end of the 2 7/8 ID ceramic heating chamber tube. The samples to be fired are placed on the top of the 2.5 wide high alumina D-tube hearth, which rests on the bottom of the ceramic heating chamber tube. Type "S thermocouples are spaced on 2 centers along the monitored zone and extend vertically through the top of the heating chamber tube. Two IFB end plugs are included to close both ends of the furnace.

Liquidus Furnace

A liquidus furnace is useful for determining the maximum temperature at which crystallization will form in a glass, and a minimum temperature at which a glass can be held for extended periods of time without crystal formation and growth.

Samples of glass, frit, or cullet are loaded into a platinum tray then placed into the hot Orton Liquidus Furnace for 1 to 24 hours. The Orton Liquidus Furnace is a specially designed horizontal tube furnace with a controlled, reproducible, linear thermal gradient of approximately 120°C across a 12" long monitored zone, the glass temperature in the tray corresponds to its position along that 12" zone.

The tray is removed hot and allowed to quench cool, freezing the glass in the state it developed inside the furnace. Upon visual, or microscopic inspection, the crystal boundary plane (the Liquidus Point) is located and the temperature of that plane is interpolated from the temperature / position relationship of the known gradient.


Gradient Furnace (1200°C max.)

Furnaces designed with lesser temperature requirements have lower cost. 1200°C max temperature furnaces share the same design features as the higher temperature units but can use lower cost insulation packages, heating elements, power controls and thermocouple sensors.

If your application requires max temperature of 1200°C or less, contact Orton for a special quote to meet your gradient furnace needs.

Contact us for quotation or to discuss your application;

or call +1-614-818-1320



12" (30.48cm) monitored zone


16" (40.64cm) monitored zone

Gradient Furnace _edited.jpg
gradient furnace testing a sample
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