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"An admission of steam occurs about once in every thirty revolutions at approximately full load. The pilot valve is continually oscillating, thus preventing any liability of sticking, but its period of oscillation is varied directly by the governor. Steam, therefore, enters the turbine in puffs, the duration of which depends upon the load; at slight overloads the valve would be constantly open." —Derr, 1911

Turbine Governor for Varying Time of Admission

"An admission of steam occurs about once in every thirty revolutions at approximately full load. The…