Victory Ship Propulsion

What made a Victory ship move? The 1944 vintage cutaway drawing below shows how.

Boiler exhaust heats the feedwater in the economizers above each of the two water tube boilers. These were built by Babcock and Wilcox, Combusion Engineering and perhaps other suppliers.

Feedwater passing through the boilers expands as steam collected in the steam drums, from which 450 psi steam is fed to the high pressure turbine. Depleted steam then passes through the larger low pressure turbine. Both steam turbines drive the reduction gears. General Electric, Westinghouse and Allis-Chalmers were among the vendors that furnished the turbines and gearboxes.

VC2-S-AP2 class ships had turbine and gear combinations rated at 6000 horsepower while the VC2-S-AP3 were 8500 hp vessels. Bowditch, Dutton and Michelson were in the latter category.

Boiler water levels and pressures are monitored on the boiler gage panel. The throttle board (not shown) was adjacent to the high pressure turbine. Here steam applied to the turbines was controlled according to the speed (and forward and aft direction) requested from the pilot house.

The reduction gear was directly coupled to the 160 foot long drive shaft and the 18 foot diameter four blade bronze propeller at the stern.

Here is a diagram of the main 450 pound steam system used to propel the Victory ship:

And here is layout diagram of the engine room's lower level:

The heavy, viscous residual fuel known as bunker c was pumped from settling tanks just forward of the engine room, then heated in the fuel oil heaters. Each boiler had four burners where fuel was injected for combustion.

The chilled water pumps and compressors for air conditioning were not present in the original Victory ships. This diagram is for a modified vessel. More about this below.

Here is a layout diagram of the engine room's upper level:

The refrigeration equipment shown aboave supported the large walk-in refrigerators and freezer on the second deck, starboard aboard Victory ships.

Below is a drawing of the General Elecrtic steam turbine/reduction gears as installed on some of the VC2-S-AP3 vessels:

Below is a diagram of the propeller drive shaft and bearings:

Above at left the shaft alley aboard SS Lane Victory, one of the three remaining Victory hulls afloat. A model showing the propeller and rudder on a Victory ship is seen at right.

A note about the layout drawings shown above (labeled plates 1, 2, 8 and 9):

These are taken from a set of drawings made in 1964 of the mechanical systems aboard technical research ship USS Liberty, a modified Victory VC2-S-AP3 hull, originally built as SS Simmons Victory in 1945. This was the intelligence gathering ship attacked and nearly sunk by Israeli forces during the six day war in 1967, with 34 American sailors killed and 171 wounded.

The USS Liberty drawings reflect the original SS Simmons Victory mechanical systems with two main exceptions.

The electrical system was changed to alternating current (AC). The original two 120/240 volt DC turbo generators were removed and replaced with three 450 volt three phase turbo alternators driven from the 450 pound steam system. Air conditioning machinery was also added. Otherwise the drawings are reasonably accurate depiction of how a Victory ship's systems functioned.