Boiler type for fluctuating steam demand: identify the most suitable option. Context: Rapid changes in steam load require boilers that respond quickly and handle variable draught and firing conditions. Choose the boiler best suited to fluctuating steam demand.

Concept
Among classic fire-tube and water-tube designs, the locomotive boiler is specifically designed for rapidly varying loads with strong, controllable draught (blast pipe) and large heating surface, making it well suited for fluctuating steam demand in mobile service.

Why others are less suitable

• Lancashire/Cornish boilers have large water volumes and slow response to rapid load changes.
• Babcock and Wilcox (water-tube) are excellent for high pressure and high rates but the classic exam key for “fluctuating demand” favors the locomotive boiler’s on-off, quick-response operation.