Heating furnaces have a large number of apertures, for example, raw material charging ports, extraction ports, and cracks in the furnace ceiling and side walls. If the pressure inside the furnace is too high, flame and heat is forced out of the furnace resulting in unnecessary heat losses. If the internal pressure is too low, then cold air is sucked into the furnace increasing fuel consumption. The pressure gradient also shows variation across the furnace length.  The furnace pressure control technology aims at maintaining optimum presssure in different parts of the furnace to minimize energy consumption. 

This technique is generally applicable to industrial furnaces, rolling mill reheating furnaces included.  However, no information on specific application in the rolling mill exists. The saving information proovided below is for an industrial drying furnace and is intended to exmplify the technique's potential.