Shield Section

Shield Section


The shield section contains the tube rows that "shield" the convection rows from the direct radiant heat. Just below the shield tubes are two important monitoring points. The first is the "bridgewall" temperature which is the temperature of the flue gas after the radiant heat is removed including the radiant heat to the shield tubes above, but before the convective heat to the shield tubes. The other is the draft measurement at this point, since for most heater designs, if it is negative at this point, it is negative throughout the furnace.