The triple-expansion pumping engine developed by Irving H. Reynolds was first purchased by the City of Milwaukee in 1886. Its success led to orders from cities all over the country.

Sales picture for triple-expansion engine.

Triple-Expansion Engine in place.
Larger view (1.3 Mb).

The rapid development of an urban, industrial society in the late 19th century placed enormous pressures on the municipalities in their attempts to provide basic services. Among these services, the increasing demand for fresh water by industry and private citizens posed a continuing problem. The Allis Company, predecessor of the Allis-Chalmers Corporation, had provided nearly all the pumps used in the Milwaukee water system, and a great many for other cities. But while the pumps devised by Edwin Reynolds in 1880 and 1884 were a vast improvement over the Hamilton pumps of 1874, they were not efficient enough to revolutionize municipal pumping systems and thereby seize a large portion of the growing market. The man who did this was Reynolds’s nephew, Irving H. Reynolds, whom the elder Reynolds brought to Milwaukee in 1884.

Working from his experience with marine engines and the pumps that the Reliance Works had produced from 1874 to 1884, Irving Reynolds set to work to reduce pulsation in the water main, save fuel, and deliver greater durability in a pump that could be serviced more easily. Working almost every night and every Sunday for two years, he finally developed his own engine, which he called the triple-expansion pumping engine.

Milwaukee planned a high-service station and, in May 1886, advertised for a six million gallon compound engine. The Allis firm submitted three bids, the most expensive of which was the new triple-expansion pumping engine. By virtue of its bidding rules, the City could choose any of the bids in a multiple bid group and did choose the new engine. The Reynolds proposal called for a vertical, triple-expansion engine guaranteeing a duty of 115 million foot-pounds of work per 100 pounds of anthracite coal; this rating compared to a guarantee of 100 million foot-pounds for a three-cylinder compound engine. When installed, the actual output of the new pumping engine was 118,186,312 foot-pounds per 1000 pounds of steam, a conversion rate of approximately 15%.

In 1891 Reynolds also built a triple expansion-pumping engine for the North Point Station with a capacity of 18 million gallons per day, developing 154,048,704 foot-pounds of work per 1000 pounds of steam. This engine proved so incredibly economical that some skeptical engineers challenged Allis’s integrity, accusing him of deliberately hoodwinking the municipalities of the nation. The argument was resolved in 1890 when Professor John Carpenter of Cornell University headed a team that subjected the engine to extensive tests. The results of the tests appeared in a paper by Dr. Robert H. Thurston, Dean of the College of Engineering at Cornell, read at a meeting of the American Society of Mechanical Engineers, vindicating the Allis claims of performance by this new machine. Consequently, the Company rapidly gained leadership in municipal pumping, which it maintained for thirty years until the triple-expansion pumping engine gave way to turbine-powered centrifugal pumps in the 1920’s.