Flat Glass Tempering

PROFITABILITY + SUSTAINABILITY + ENERGY SAVING IN ONE PACKAGE

WASTE TIME   
    • Tempering and cooling time is always the same with the same thickness of glass! Note different scale in the graphs.
    • Profit comes from = heating time – (tempering + cooling) time.      
”THE MOST EFFECTIVE NOZZLE BOX”   
        • I discovered 2021 the secret of CONVAIR in 2021 HEAT TRANSFER PLATE but forgot importance of RADIATION PANEL  The HEATING WIRES cannot stand thermal shocks when cold glasses enter the furnace.  

      • Heating wires heat the RADIATION PANEL and the HEAT TRANSFER PLATE to a high temperature. 
        • The RADIATION PANEL is near the glass.  Therefore, it radiates strong. 
        • The radiation panel is thin.  It heats fast. Therefore, radiation heating is more time effective.     
      • NOZZLE BLOCKS protect heating wires and not cooling heating wires.     
      • RADIATION PLATES are removable. Heaters wires change is easy.  
”THE ADDITIONAL HEATERS”
    • THE ADDITIONAL HEATERS allows  = ”unlimited” heating speed = profit. The condition is, that glass thicknesses  should be <= 10 mm. Then tempering is not breaking thicker glasses. And not breaking thick glasses in furnace.
    • The heating time depends on the only how high temperature convection air can be heated.    
    • You can make build furnaces as long as you like.  Continuing furnaces can be even more than 60 % shorter than radiation heating furnaces.     

    • Why heating speed is ”unlimited”?  Formula of heating speed = capacity = h x A x (TSM – TCA). 
        • Where h = same for everyone, (heat transfer coefficient from sheet metal to convection air). 
        • A =  convection area (m²)  
        • TSM  = temperature of sheet metal to which heats the convection air and
        • TCA = convection air temperature.  It works also to the glass, with effective convection. 
    • ”The additional heaters”  costs only fraction of tempering machine price.  Otherwise you should buy 2 tempering furnaces!”  

 

  • CONVECTION UNIT ADVANTAGES
    • The thermocouples are more accurate and respond faster when they are in return air flow.
    • Convection jets heat glass even between the convection units.
    • Convection pressure is in the convection units which is a closed box.  No leakage of hot convection air, no energy waste.
    • The additional heaters are changed through the side walls and insulation.
    • Pressurized convection air in GLASTON FC-series E type and Land Glass furnaces in nozzle boxes or pressure boxes. In those furnaces it is difficult. In FERACITAS it is easy.  No sealing problems. No energy losses. 
    • Maximum radiation can be obtained by if nozzle boxes are installed in 90 degrees angle to the glass travel direction.
  • HEATING CONTROL
    • Automatic sending to the tempering section is possible following the principle described under the graph.  This is especially the heating process is based on the following of the furnace temperature of rather than than heating time (seconds).

TECHNICAL DATA

    • Energy consumption is hard to measure in (kWh/m²).  This is why it is used as the sales argument for tempering furnace sales.  
    • High convection power, over 10 kW/m² means energy consumption of 0,15  – 0,2 kWh/m², too. 
    • High heating power does not increase energy consumption. It saves energy consumption.     

HISTORY OF GLASS HEATING from CONVAIR in 1996 to FERACITAS INVENTIONS in 2026

  • CONVAIR was built in 1996, according the best radiation heating furnaces. Read Linked article  https://www.linkedin.com/pulse/glass-tempering-control-systems-risto-nikander-nrsyf/ . It was supposed to be convection + radiation heating process.  It had high capacity, clear 5 mm glass 26 loads/hour and triple silver glass 22 loads/hour.  It started immediately with no problems. Patent for CONVAIR was US 6470711B1 was wrong claimed!  Convection power was 5 kW/m² and heating power 80 kW/m².  It had invented in 2021 CONVAIR no radiation but capacity was so high as mentioned. It was revealed that convection heating has 60% higher capacity than radiation heating.  
  • GLASSROBOTS built RoboTemp.  It was basically copy of CONVAIR in 2003.  GLASSROBOTS was tried to heating speed increase convection power to 10 kW/m².  The capacity remained the same. Patent document US7448232B2.
  • In 2010 GLASTON tried to increase heating speed convection power to 13 kW/m² and heating power to almost 100 kW/m².  The capacity was reduced 30%.  Clear glass capacity was 20 loads/hour, triple silver (E 0,02)  capacity was 16 loads/hour.  GLASTON informed energy consumption 5 mm glass clear glass,  3,0 kWh/m² and triple silver glass (E 0,02) 3,3  kWh/m².  It was really at least 3,8 kWh/m² and 4,2 kWh kWh/m².   Maybe 0,15 – to 0,2 kWh/m² higher, because convection power is not included in total energy consumption!
  • In January 2021,  Risto Nikander invented that that it has not radiation but convection capacity was 60% higher than radiation! I applied patent.  
  • I informed ex CEO that GLASTON patent US8618442B2 eliminated convection heating and radiation. Nothing happened.
  • When Finnish patent expired in January 2022 GLASTON could use it in convection furnaces.
  • There is still ”radion panel”.  See ”THE MOST EFFECTIVE NOZZLE BOX” and
  • ”THE ADDITIONAL HEATERS”  

  • It took almost 25 years to recover CONVAIR secret and 27 years to have radiation + convection put together!

 

CHEAPER CONVAIR I, box construction 

CHEAPER CONVAIR II, bottom convection

CONCLUSION

It is very hard to invent simplest and the best working solutions.  In reality, 90 – 99% of technology exist.  Simple 1 – 10% inventions can make wonders.