Engineering Wonders of the World
Volume III

THE KINLOCHLEVEN ALUMINIUM WORKS. 277 Governing the Water. hand or by an automatic governor, pro- duce a corresponding change of the dis- charge area of the nozzle ? and so vary the size of the jet and the power of the wheel. The pressure of the water is so great that the needle cannot be worked direct from the governor, but requires the interposition of a servo-motor to do the hard work. The governor itself is of the familiar centrifugal weight type. An in- crease of speed causes two weights, sus- pended by links from the top of a revolving vertical shaft, to fly outwards and, through two other links, to move upwards a grooved collar sliding on the shaft. A decrease in speed moves the collar downwards. This collar operates a small valve, which in turn controls another valve admitting oil or water under high pressure to either side of the piston of a servo-motor. This piston is coupled direct to one end of a lever, which is the first of a series operating the nozzle needle valve. As a sudden diminution in the discharge would naturally cause a great temporary increase in the pressure of the pipes, the speed governor is arranged to perform a second duty—that of opening an escape valve when the needle valve is closed, and closing it when the needle valve is opened. The two valves are so adjusted that under all conditions the total amount of water passing through them remains unaltered. If a stoppage of the tur- bine becomes necessary, its sluice valve is shut gradually by hand. Each turbine is connected direct to a pair of generators mounted on a single shaft of mild steel. Each of the main generators has a normal full load output of 1,000 kilowatts, INTERIOR VIEW OF THE KINLOCHLEVEN POWER-STATION, SHOWING THE EIGHT 3,200 HORSE-POWER TURBINES, AND THE EIGHT PAIRS OF GENERATORS DRIVEN BY THEM. when rotating at its normal speed of 300 revolutions per minute. As these generators have to run at full pressure continuously for months at a time, provision is made for The Generators. effecting all necessary adjustments, renewal of brushes, lubrication, and cleaning while they are in motion. Sets of smaller dynamos are used for light- ing the factory and village and generating current for the double-track electric railway which connects the factory with a quay at the head of Loch Leven. [Note.—Thanks are due to the British Aluminium Company Ltd. for supplying much of the information in this article and several of the illustrations.']