Engineering Wonders of the World
Volume I

302 ENGINEERING WONDERS OF THE WORLD. ONE OF THE NIAGARA FALLS POWER COMPANY’S 5,000 HORSE-POWER TURBINES. {Photo, Orrin E. Dunlap, Niagara Falls, N.Y.) below the power-house floor ; and from them is sent out over feeder cables enclosed in underground ducts to local , ,, Transformers. consumers, or to the step- up ” transformer stations for transmission at higher voltages to distant towns and indus- trial establishments. This change of tension, designed to decrease as much as possible the transmission losses and cost of trans- mission lines, is effected by a number of air-blast or oil-insulated, water-cooled trans- formers, of capacities ranging from 1,250 to 2,500 horse-power. The transformer plants on the American side change the current from 2,200 volts to 11,000 or 22,000 volts, as may be required; Ayhile the transformers of The total weight of the revolving parts of each turbine and electric generator, together with the sections of hollow and solid shafting connecting the two, amounts The jn some cases to 66, in others Machinery. _ , . to 112, tons. To support and counterbalance these ponderous masses of revolving metal, are used, first, the upward pressure of water in a compartment of the turbine wheel-case acting upon the lower surface of a disc secured to the shaft; and, greater capacity included in the Canadian company’s plant convert the generated current from 11,000 volts, three-phase, to 22,00'0, 33,000, 38,500, or 57,500 volts, three-phase, by slight changes in the connections. All three plants are linked up by heavy copper cables, so that power generated in any- one may be sent out direct to the consumers usually supplied by it, or transmitted to either of the other two plants for similar distribution. The system consequently is a secondly, a thrust-bearing, vertical shaft just below the power-house floor. In No. 2 power-house of the Niagara Falls Company, and in the Canadian plant, the thrust- bearing consists of two discs, between which oil is forced under pressure, the lower disc being stationary, and the upper one attached to the •revolving shaft. From th© generators the power, now converted into electrical energy, is distrib- placed in each single unit of great flexibility with ample v D SKETCH SHOWING GENERAL ARRANGEMENT OF NIAGARA FALLS POWER COMPANY’S INSTALLATIONS. P, penstocks; S, shafts, in wheel-pits, at the bottom of which are the turbines. uted through copper cables to the main copper “ bus ” bars placed in a subway