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Show Fig. 6 - Direct-Fired Regenerative Burners In addition, the direct-fired models are being proposed for: Heat Treat and Annealing Furnaces 5 Zone Steel Re-Heat Furnaces Skelp Furnaces Ladle Heaters Crucible Furnaces Periodic Kilns Fig. 7 - Radiant Tube Regenerative Burners 68 Ble.d I1'Alr \:.J Inlet Fig. 8 - Radiant Tube Burner-Fire Mode \~:.A.Il Irnle t Tube Inauletlon Sle .... e • U·Tube • Fig. 9 - Radiant Tube Burner - Flue Mode • The radiant tube regenerative burner is shown in Figs. 7, 8 and 9. The heat reclamation bed, surrounded with insulation is contained in a cast iron burner body. In the fire mode, gas flows through a compressed air operated cycling valve, a flow adjusting valve, and finally the fuel tube. The gas is ignited with a pre-mix pilot tip. Combustion air enters the burner body through an eductor jet nozzle. During the firing mode (left burner in Fig. 7 and sectional view in Fig. 8) the flapper valve on the eductor outl~ is nearly closed, forcing most of the air to travel through the heat reclamation bed and mix with the gas to fqrm a long, luminous flame. The combustion air is throttledby adjusting the bleed rate out of the exhaust valve. |