RMS Mauretania Refit 1921

RMS Mauretania was originally built with 23 double-ended and 2 single-ended coal-fired boilers, each feeding her Parsons turbines at 195 psi. By 1921, Cunard used the opportunity of a fire and scheduled refit to convert this system to oil firing.

The work meant stripping out coal grates, ash pits, and chute gear, then fitting pressure-jet oil burners, adjustable air registers, and modified uptakes to handle cleaner combustion. Fuel storage was reorganised into a system of settling and service tanks, steam-heated strainers, and heaters that ensured the heavy oil reached the burners at the correct viscosity. New ring-main piping and quick-shut valves were also installed for safety.

The transformation changed daily operations completely. Stokers no longer had to shovel hundreds of tons of coal, manage clinker, or discharge ash. Instead, a reduced boiler crew monitored valves, gauges, and oil flow. The plant ran steadier steam pressure, reacted instantly to telegraph orders, and consumed about 600 tons of oil per day instead of roughly 1,000 tons of coal.

This efficiency meant Mauretania could steam a full round trip from Southampton to New York without refuelling. Her boiler rooms became cleaner, less labor-intensive, and more reliable, and in 1922 she even broke her own eastbound record, proving the benefits of oil conversion in both economy and performance.

Source: Maritime Buff