Show you the diagram of lancashire boiler?

Answer 1

The name firetube is very descriptive. The fire, or hot flue gases from the burner, is channeled through tubes that are surrounded by the fluid to be heated. The body of the boiler is the pressure vessel and contains the fluid. In most cases this fluid is water that will be circulated for heating purposes or converted to steam for process use.

Every set of tubes that the flue gas travels through, before it makes a turn, is considered a "pass". So a three-pass boiler will have three sets of tubes with the stack outlet located on the rear of the boiler. A 4-pass will have four sets and the stack outlet at the front.

Firetube Boilers are:

• Relatively inexpensive
• Easy to clean
• Compact in size
• Available in sizes from 600,000 btu/hr to 50,000,000 btu/hr
• Easy to replace tubes
• Well suited for space heating and industrial process applications

Disadvantages of Firetube Boilers include:

• Not suitable for high pressure applications 250 psig and above
• Limitation for high capacity steam generation