Cochran boiler

Characteristics: 

1. Vertical Boiler
2. Multi tube Boiler
3. straight tube Boiler 
4. low pressure Boiler
5. Coal fired Boiler  
6. Single tube Boiler
7. Natural draft Boiler
8. Natural circulation Boiler
9. Stationary Boiler
10. internally fired Boiler    
11. Water tube Boiler

Working: The fuel is burnt on the grate and ash is collected and disposed of from ash pit. The gases of combustion produced by burning of fuel enter the combustion chamber through the flue tube and strike against fire brick lining which directs them to pass through number of horizontal tubes, being surrounded by water. After which the gases escape to the atmosphere through smoke box and chimney.

Construction: Cochran boiler consists of a cylindrical shell with a dome shaped top where the space is provided for steam. The furnace is one piece construction and is seamless. Its crown has a hemispherical shape and thus provides maximum volume of space.
Advantages:

• The minimum floor area is required.
• Cost of construction is low.
• it can be moved and stet up take it to different location.
• Boiler has self contained furnace . No brick work setting is neccessary.
• Any type of flue can be used.

Disadvantages:

• Steam raising capacity is less due to vertical design.
• Difficult in cleaning and inspection due to vertical design.
• The capacity and pressure are limited.
• The boiler requires high head room.