ASME-Landmark:Hacienda La Esperanza Sugar Mill Steam Engine

The La Esperanza sugar mill steam engine is one of the few remaining American links to the pioneer beam engines of the English inventors Thomas Newcomen (1712) and James Watt (1769). The engine was built in 1861 in Cold Spring, New York, by the West Point Foundry. The general arrangement and details, including the Gothic embellishment, are typical of machinery of the period. The straight-line motion of the piston rod is accommodated to the arc of the moving beam end by a parallel motion. Watt regarded this ingenious linkage as the invention of which he was most proud.

When running on 60 PSI of steam, the engine turned at about 20 RPM and developed approximately 25 HP. To deliver maximum power, the La Esperanza engine had to run at approximately 20 RPM, but to extract cane juice efficiently the mill would have had to turn much more slowly. Double-reduction gears accomplished this change in speed.

The sugar cane plantation was founded in 1850 by Don Jose Ramon Fernandez y Martinez, Marquis of La Esperanza. The Conservation Trust of Puerto Rico restored the machinery as part of a sugar museum.

La Esperanza's decorated steam engine is the only West Point Foundry beam engine known to survive, the only known 6-column beam engine by any American manufacturer, and one of only eight beam engines of American manufacture known to exist anywhere. See ASME website for more information