Corliss steam engine

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A Corliss steam engine (or Corliss engine) is a steam engine, fitted with rotary valves, invented by and named after the American engineer George Henry Corliss. There are four valves for each cylinder, with steam and exhaust valves located at each end. With variable valve timing, engines fitted with Corliss valve gear offered the best thermal efficiency of any type of stationary steam engine until the refinement of the uniflow steam engine and steam turbine in the 20th century.

Simpler "standard" engines have a sliding shoe valve that alternately feeds and exhausts through single pipes to the ends of the cylinder. Corliss valves open directly into the cylinder. The valves connect the cylinder to separate steam and exhaust plenums. So, with Corliss valve gear, no pipes change temperature during the cycle, and the timing and pressures of the cycle are more precise. Nothing is perfect, though. Like all steam engines, Corliss engines require valve timing adjustments to reach their best performance.

Corliss engines were typically used as stationary engines to provide mechanical power to line shafting in factories and mills and to drive dynamos to generate electricity. Many were quite large, standing several stories tall, and developing several hundred horsepower, albeit at low speed, turning massive flywheels weighing several tons at about 100 revolutions per minute. Some of these engines had unique roles as mechanical legacy systems and because of their relatively high efficiency and low maintenance requirements, they remained in service until the late 20th century.

1 Company history
2 Centennial Engine
3 See also
4 External links
- 4.1 General
- 4.2 Operational Engines

[edit] Company history

The Corliss Steam Engine Company was originally known as Fairbanks, Clark & Co. in the 1830s. In 1843 it was renamed Fairbanks, Bancroft & Co. when Edward Bancroft joined the company. In 1846 it was renamed Bancroft, Nightingale & Co. when George H. Corliss joined the company, and in 1847 it was renamed Corliss, Nightingale and Co. In 1848 the company moved to the Charles Street Railroad Crossing in Providence, Rhode Island. In 1857 the company was renamed for the last time to Corliss Steam Engine Company. By 1864 Corliss bought out his partners and was the sole owner of the company. In 1900 the Corliss Steam Engine Company was purchased by the International Power Company. In 1905 it was purchased by the American and British Manufacturing Company. In 1925 the company merged into Franklin Machine Company. By then Franklin Machine Company was already owned by the William A. Harris Steam Engine Company.

Corliss' key patent expired in 1870, and after that date, numerous other companies began to manufacture Corliss engines. Among them, the William A. Harris Steam Engine Company [1], the Worthington Pump and Machinery Company [2], and Allis-Chalmers [3]. In general, these machines were referred to as Corliss engines regardless of who made them.

[edit] Centennial Engine

The Corliss Centennial Engine was an all-inclusive, specially built-steam engine that powered virtually all of the exhibits at the Centennial Exposition in Philadelphia in 1876. Switched on by President Ulysses Grant and Emperor Dom Pedro of Brazil, the engine was publicly visible for the duration of the fair. At 45 feet tall and with a flywheel 30 feet in diameter, the Centennial Engine produced 1,400 horsepower. After the fair, it was disassembled and shipped back to Corliss's plant in Providence. Seven years later it was sold and powered a Chicago factory owned by George Pullman until 1910.

This engine became a cultural icon, so much so that, to many modern historians, the term Corliss engine refers to this specific engine and not to the broad class of engines fitted with Corliss valve gear.