1. The Lancashire Boiler: The Lancashire boiler is a classic example of a stationary, internal-fire-tube boiler. It is characterized by its large horizontal cylindrical shell and, most importantly, its
two large horizontal fire tubes (flues) that run through the length of the water-filled shell.
2. Functional Characteristics:
• Internal Firing: The grate and furnace are located at the front end inside these two large tubes.
• Gas Path: The flue gases travel to the back through the two main tubes, then pass through brick-lined bottom and side flues to maximize heat transfer before exiting through the chimney.
• Pressure Range: It typically operates at low to medium pressures (up to 16 bar).
3. Comparison with Other Boilers:
• Cornish Boiler: Very similar to the Lancashire but contains only
one large internal fire tube.
• Cochran Boiler: A
vertical multi-tubular fire-tube boiler, not horizontal.
• Locomotive Boiler: A horizontal fire-tube boiler, but it contains a large number of
small-diameter tubes rather than two large flues.