The temperature difference between the upper and lower sections in the furnace is large, the upper part of the billet is high, the underside of the bottom is low, the underside of the bottom is poor, and the cause of dark fire is as follows:
Firstly, the form of pallet stacking is unreasonable, which neglects the density principle of the code kiln with high density and low density.
Second, when the internal combustion brick is burning, the air at the bottom is too large, the kang leg is too thin, the air intake is large,the heat preservation belt is short, so that the lower part of the billet mound cools quickly and the fire goes out early.
Third, when the external combustion brick, the kang leg is low, the fuel ash is too large, the coal ash and cinder block the lower fire channel and the system pumping power is insufficient, which makes the bottom of the billet stack unventilated and causes the bottom fire to be bad.
Fourthly, the form of fire hole batch piling is unreasonable, and the proportion of the fuel input is uneven at the top, middle and lower parts and the bottom of the kiln. Too much or too little at the bottom will cause a large temperature difference under the intermittent surface of the kiln.
Fifth, due to the humidity of the kiln bottom and kiln body, some of the heat is wasted, or the insulation layer of the tunnel kiln car is not enough, resulting in the heat loss of the kiln car is too large, resulting in a large temperature difference in the kiln.