The best way to understand a Vacuum Insulated Glass unit is first to think about a Thermos container.What exactly is a Thermos container? According to one definition, it is vacuum flask, which is an insulating storage vessel that greatly lengthens the time over which its contents remain hotter or cooler than the flask's surroundings; Your coffee can stay hot for hours or your cold drinks can stay cold for hours. The science behind a Thermos has to do with the fact that the air has been pumped out between two substrates and then hermetically sealed. Once the air is pumped out and a seal is in place, there are no longer molecules that can transfer heat or cold.
A Vacuum Insulated Glass Unit, (VIG), uses the same concept. When you vacuum out the air between two glass substrates, then hermetically seal them you pump out all the molecules. Where there are no molecules there is no heat that can be transferred through conduction or convection. Now, add high performance Low Emissivity Glass and you reflect almost all radiation heat. Now you may have the perfect insulating glass unit.....the VIG.
A Vacuum Insulated Glass unit consists of two glass pieces hermetically sealed at the edges with glass spacers as thin as a human hair, (0.25mm), keeping the two glass pieces from touching each other. These “pillars" or spacers occupy so little surface area that their conductive heat loss is negligible. They are small enough that they are not visible from more than a few feet away.
In the construction industry, insulation value is often referred to as R-Value and U-value. This is a measure of the resistance of an insulating or building material to heat flow, expressed as R-1, R-2, R-3 and so on. The greater number the greater resistance to heat flow. The U-value is also a measure used in the construction material industry. It is also measure of how much heat is lost through a given thickness of a particular material. The higher the R-Value the better the insulation, Conversly, the lower the U-value also the better the insulation.
In Normal Gas-filled Insulated double glass Units, (IGU), thickness is a compromise between maximizing insulating value and the ability of the framing system used to carry the unit. The current prevailing insulating glass technology may replace air in the space between two panes of glass with a lower thermal conductivity "gas" such as Argon, Krypton or Xenon to achieve higher insulation R-value or lower U -value. Krypton and Xenon are, however, very expensive. A top-of-the-line triple-glazed unit filled with Krypton or Xenon gas can also currently claim a high center-of-glass R-value closer to a VIG unit, however, they are very thick, heavy and expensive to frame. VIG units promise to equal or exceed the thermal performance of triple glazing with less weight bulk, and less cost to frame.
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THE BEST GAS IS NO GAS AT ALL
The most thermally efficient gas fill would be no gas at all—a vacuum –in which the space between surfaces two and three are evacuated to a minimum of less than one millionth of normal atmospheric pressure. At that level, there is no conductive or convective heat exchange between the lites of glass. Now, add high performance low E glass and you have increased the R value maybe 5 times or more of that of a regular insulated Glass unit, (IGU).
LANDGLASS AND IGE GLASS TECHNOLOGIES MAKE FIRST TIME VIG ANNOUNCEMENT AT GPAD 2015 HELD IN SAN ANTONIO TEXAS.
With building energy savings, safety and aesthetics in mind, LANDGLASS of
Luoyang China, distributed by IGE Glass Technologies, Headquartered in Jupiter Florida, USA, has developed a revolutionary new way of manufacturing "Tempered" Vacuum Insulated Glass, (TVIG). Landglass and IGE have been quietly developing this product and manufacturing process for more than five years and recently at the 2015 GPAD conference in San Antonio Texas, announced their plan to offer the equipment and technology, for the first time worldwide, to the Glass Industry starting late this year, 2015.
While the concept of VIG is not new, the introduction of a more esthetically pleasing unit and use of "tempered safety glass" as well as the streamlined manufacturing process is new, according to the announcement by Spellman and Frey of IGE Glass Technologies Inc., The LandGlass VIG line has developed a way to vacuum out the air without an unsightly pumping hole. They also figured out how to hermetically seal these units at a lower temperature, therefore, allowing the use of tempered safety glass. Furthermore, the Langlass system for manufacturing these units is streamlined and automated which Spellman and Frey say is truly revolutionary for the manufacturing of VIG units. The entire process from cutting the glass to completion of a unit including the vacuum, pillar placement, sealing and tempering is done on one horizontal line. In order to meet the anticipated demand for these production lines, LandGlass has recently completed the construction of a 2 million square foot building in Luoyang China. To put this size building in perspective, it is about forty acres under roof.
LandGlass is looking to achieve a goal of R-10, R-12 or higher. This would make a LandGlass VIG unit with an insulation value equal to that of a studded insulated wall. With "window to wall ratio" a great concern to the glass manufacturer, this is big news according to Spellman and Frey. Tempered VIG also offer other benefits such soundproofing, anti-dewing properties, wind load resistance, high-performance and longevity to building facades compared to the traditional insulating glass units, IGU.
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Questions ask to Mr, Spellman, IGE Glass Technologies, Inc.
1) What is the minimum and maximum size VIG that can be produced on the LandGlass production line ?
Maximum size is 1.5x 2.5 meters, 59" x 98"...Minimum size is ? 400mm x 900mm or 16" x 36".
2) What kind of glass can be used for Vacuum Insulated Glass?
Answer: clear, coated, and printed glass are all acceptable. As mentioned adding a good low e coated glass will increase the R-value.
3) What is the production capacity of the line?
Answer; current design can produce 3 million square feet per year.
4) What is the metal compound used in LandGlass's VIG?
Answer; at this date it is privileged and confidential information.
5) Will LandGlass/IGE sell the VIG units?
Answer: No.....not in North America. However, the possibility remains that LandGlass/IGE will sell units to the first customer while their line is being built and their people are being trained. They will sell units in a China to the Chinese market only.
6) What will be the cost of the line?
Answer: Yet to be determined but understanding that they are using vacuum technology and Cyclone full top and bottom convection glass tempering furnaces it will be many many times more than the cost of normal IG lines.
7) How much space is required to create a turn key production facility?
Answer: we estimate about 100,000 square feet.
8) Does Landglass have this system patented?
Answer; as of today, LandGlass has over 50 technology patents. Our patents cover Asia and overseas countries including the US/Canada South America and Europe.
9) What kind of companies will you target to purchase this equipment and technology?
Answer: We have a plan A, B and a C. That's all I can say at this point.
10) What is the life of the unit?
Answer; our testing leads us to believe the life to 40 years or more.
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