• Steel Plant Specialities LLP

Coating for Furnaces

Furnace oil is widely used in India as a fuel in furnaces in hot rolling and die casting. The following problems are encountered in the furnace operation: 1. Thermal shock cracking ? thermal shock is unavoidable in furnace operation, however much care may be taken. Due to thermal shock, cracks are initiated in the refractory lining. Energy leaks through these cracks. This loss may be as high as 33% of the total energy consumption. This is the reason why fuel consumption is observed to be more after a time gap of say, six months from the date of relining the furnace, for the same level of production; 2. Low emissivity ? refractory lining has a low emissivity of 0.2 and hence hampers furnace efficiency. Improving this value to 0.5 or more will lead to fuel saving; 3. Corrosive action ?furnace oil contains sulphur dioxide and vanadium pentoxide. These compounds corrode the refractory lining; 4. Vicious sand blasting effect ? the flame impinging on the refractory lining has a vicious effect of sand blasting; and 5. Carbon deposit on the burner blocks. This problem is more pronounced when the fuel used is furnace oil. Unburned carbon deposits on the burner blocks, and over a period of time, sufficient carbon build up takes place. Due to this build up, the flame geometry is impaired and heating efficiency is lowered. Steel Plant Specialities, a Mumbai based firm has come out with a unique solution to overcome all the above problems. The entire refractory lining of the reheating furnace is coated with a special coating ESPON-RC. This can be useful in achieving substantial savings in fuel consumption. This technique is a sure way of cost reduction.