Thermal Insulation & Refractory Materials to reduce large amount of heat by combustion of fuels in closed compartments and to controlled temperature and pressure while in boiler furnace the temperature is with in 1350 c many industrial and melting furnaces operate at temperature between 1300 c and 1600 c hence various types of refractory bricks are used to resist high temperature and other strains on the hot side with back up layers of different grades of insulation bricks which retain the heat and retard its rate of flow minimizing losses.