Cochran boiler
It is a multi-tubular vertical fire tube boiler having a number of horizontal fire tubes. It is the modification of a simple vertical boiler where the heating surface has been increased by means of a number of fire tubes.
In this boiler, the fire tubes are placed horizontally.
The efficiency of this boiler is much better than the simple vertical boiler.
Main Parts of Cochran Boiler:
The Main parts of Cochran boiler are:
1. Shell
2. Grate
3. Combustion chamber
4. Fire tubes
5. Fire hole
6. Firebox (Furnace)
7. Chimney
8. Man Hole
9. Flue pipe
Cochran boiler
Shell:
The main body of the boiler is known as a shell.
It is hemispherical on the top, where space is provided for steam.
This hemispherical top gives a higher volume to area ratio which increases the steam capacity.
Grate:
The area where the fire is placed known as a grate.
ertisement: 5:15
It is placed at the bottom of the furnace where coal is burnt.
Combustion Chamber:
It is lined with fire bricks on the side of the shell to prevent overheating of the boiler.
Hot gases enter the fire tubes from the flue pipe through the combustion chamber.
The combustion chamber is connected to the furnace.
Fire Tubes:
There are various fire tubes whose one end is connected to the furnace and other to the chimney.
A number of horizontal fire tubes are provided, thereby the heating surface is increased.
Fire Hole:
The small hole is provided at the bottom of the combustion chamber to place fuel is known as a fire hole.
Fir Box (Furnace):
It works as a mediator of fire tubes and combustion chamber.
It is also dome-shaped like the shell so that the gases can be deflected back till they are passed out through the flue pipe to the combustion chamber.
Chimney:
It is provided for the exit of flue gases to the atmosphere from the smokebox.
Man Hole:
It is provided for the inspection and repair of the interior of the boiler shell.
Flue Pipe:
It is a short passage connecting the firebox with the combustion chamber.