Three-drum water-tube boiler historically used in marine service.
What to learn
Study the pressure parts, combustion or heat source, water and steam circuit, gas path, circulation method, mountings, controls and normal operating range.
Construction and flow path
Identify each major component and trace fuel, air, flue gas, feedwater, steam and blowdown from entry to exit.
Operational significance
Relate load response, water inventory, pressure capability, fuel flexibility, efficiency and maintenance access to the boiler design.
Failure and inspection focus
Examine overheating, corrosion, erosion, deposits, cracking, leakage, support defects, combustion problems and control failures.