Zubler USA
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Patrick, please excuse me while I explain this feature of our oven.
Those of you that understand physics understand thermal resistance. When you are pressing, the investment is a thermal blanket, enveloping the ingot. The plunger on top, also acts as an insulator. NO MATTER what temperature is displayed on your furnace at any given point during a TRADITIONAL program, the temperature inside the ring will never match the temperature of the chamber or the temperature on the outside of the ring.
Thus you have a temperature differential across the interior of the ring all the way to the outside and into the chamber. In traditional programs you have a heat rate to a final hold temperature for a specific number of minutes before you press either intelligently or for a programmed number of minutes. Take this program for example:
Entry 700c
Heat rate 60C/min
Final temperature 915C
Hold time 25 min
Press intelligent
In this program, you can bet when you begin to press the outside of the ring is approximately 915C, however the inside of the ring is between 880C and 885C. So where is most of the reaction layer on this pressing if it is Lithium Disilicate? obviously where it was over heated.
With the advanced press feature, the ring is between 880C-885C all the way across. The ingot stays in the most conducive temperature zone and never sees as much heat as the TRADITIONAL program.
Those of you that understand physics understand thermal resistance. When you are pressing, the investment is a thermal blanket, enveloping the ingot. The plunger on top, also acts as an insulator. NO MATTER what temperature is displayed on your furnace at any given point during a TRADITIONAL program, the temperature inside the ring will never match the temperature of the chamber or the temperature on the outside of the ring.
Thus you have a temperature differential across the interior of the ring all the way to the outside and into the chamber. In traditional programs you have a heat rate to a final hold temperature for a specific number of minutes before you press either intelligently or for a programmed number of minutes. Take this program for example:
Entry 700c
Heat rate 60C/min
Final temperature 915C
Hold time 25 min
Press intelligent
In this program, you can bet when you begin to press the outside of the ring is approximately 915C, however the inside of the ring is between 880C and 885C. So where is most of the reaction layer on this pressing if it is Lithium Disilicate? obviously where it was over heated.
With the advanced press feature, the ring is between 880C-885C all the way across. The ingot stays in the most conducive temperature zone and never sees as much heat as the TRADITIONAL program.
s....
