EXCESS AIR RATIO CONTROLLING DEVICE OF COMBUSTION APPARATUS IN COMBUSTION WITH PREHEATED AIR

摘要

PURPOSE:To obtain a low price but high performance fuel-air ratio controlling device by installation of a control valve being controlled depending on air temperatures in the downstream side of an equalizer valve in an apparatus where the equalizer valve controls fuel-air ratio. CONSTITUTION:A burner 1 operates with supply of gaseous fuel through a gas line G equipped with an equalizer valve 5 and of properly preheated air through an air line A equipped with a temperature control valve 2 and a heat exchanger 3. The equalizer valve 5 is controlled depending on the air pressure in the air line A through a line having a cooler 4. The gas line G is provided with a control valve 6 in the downstream side of the equalizer valve 5. An apparatus is constructed to modify and control the fuel-gas rate after equalizing through a controller 7 which controls opening of the control valve 6 depending on outputs of a thermocouple 8 detecting the preheated air temperature in the air line A.