Combustion of fuel takes place in the combustion chamber consequently heat is generated and traned to the water in the tubes.
Heat transfer takes place by conduction ,convection and radiation.
Burners :
The function of burner is to mix fuel and air to project the mixture in the combustion chamber of burning.
Boiler walls and lining :
The boiler walls are made of refractory material and are heat resistant and provide adequate heat insulation.
Steam and water drum :
The stem and water drum is mounted on the top of the boiler and is connected to the water tubes placed inside the boiler, by header.
Tubes and headers :
The tubes are arranged in three or four groups connected to each other and the water drum by headers.
Brick work :
The entire brick in boilers comprisesilica bricks because of their ability to resist corrosion and withstand high temperatures.