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Unique Twisted Design of Ceramic Insert Saves Energy for Metal Heat-Treating Furnaces

Radiant tube heaters are typically used in metal heat-treating furnaces. The heaters are long tubes, often in a U shape, which have natural-gas fired burners at one end of the tube (the burner leg) to produce a flame and heated gas that flows through the tube to produce heat for conditioning metals (e.g., strengthening them or otherwise changing some of their properties). In a traditional radiant tube, the burner leg releases 30% more energy than the exhaust leg because of convection and radiation heat transfer in the burner leg.

With the help of a grant from DOE's Inventions and Innovation Program, STORM Development LLC and Sycore Inc. optimized the SpyroCor, a ceramic (silicon-carbide) insert for the exhaust leg of the tube heater. The patented twisted design of the SpyroCor produces nonturbulent, high convection flow that produces the highest possible rate of uniform heat transfer. As a result, the SpyroCor reduces heat loss and the energy demands of the process or application by 15% to 20%. A typical furnace contains 10 radiant tubes, which use an average of 3 SpyroCors per tube. Through 2011, 612 furnaces have been equipped with SpyroCors for a savings of 13.1 trillion Btu.

Energy Savings (Trillion Btu)0.2350.4961.1901.4701.8302.2402.5803.050
Emissions Reductions
(Thousand Tons)
SpyroCor Installed in a Radiant U-Tube Heater.
SpyroCor installed in a radiant U-tube heater.


  • Developed by STORM Development LLC and Sycore Inc.
  • Commercialized and being marketed by Spinworks LLC.
  • Sold more than 23,000 units through 2011.


Can be used in radiant tube heaters typical in metal heat-treating furnaces that use natural gas burners or in industrial radiant tube space heaters.


  • Produces nonturbulent, high convection flow in the radiant tube.
  • Doubles the amount of surface area available for heat transfer.
  • Balances the heat transfer throughout the radiant tube, allowing more energy to be available to the load.


Ease of Installation

Can be quickly and easily inserted into existing heater tubes without overhauling the entire furnace.


Allows the furnace user to increase the amount of metal treated for the same amount of energy used or to reduce the amount of energy used for the same output.


Tom Briselden
(814) 440-2604
Spinworks LLC