THE NEW TURBINE.

Dominion, Volume 2, Issue 608, 10 September 1909, Page 8

THE NEW TURBINE.

SUCCESSFUL TRIAL YESTERDAY. The largo electric generator ' which has been undergoing, erection at the Tramway Power House, Jervois Quay,' for Some '.time' past, was put into commission for tho first time on 'Wednesday,' .with- , very/satisfactory results. ■ - '~'■■. ''.'.•' '..)■ '~:;■:, •: ■'■ .■' The now'machine stands , on-a massivo block of concrctc-SG feet'long,-'l'4 c and ,10 feet deep, built.- on > top;, of s con6r'eto piles,' arid, viewed from the'basement-of'-the engine-room, tho' set has' ah'imposing dp-' pearance, towering,up to a-height;of-,24 feet from the basement lloor. '.'' '•" '. , . '.. . Tho ollginc, which was.i constructed by Messrs.. Belliss and 'Morcbm,'of .'Birmingham', is in general accotdahce with' tliis well-known firm's triple .oxpansion type/- with■':• cylinders 18 inches, 27 inches,, and-40 inches in diameter . resptctivcly;' aiid'a' stroko 'of 20 inches, MTion 'running revolutions per'minute on--normal.'full load; this p'nginb will develop .1100 brake horse-power. • A number of improvements. havo.;been adopted by the makers, and these." iiloludo tho. introduction of. a steam relay cylinder, in:.connection with tho variable expansion valve, which will-permit tho . engine to instantaneously respond to tho rapid variations, in the tramway load,; and at the, samo time will give a well-balanced turning, movement-to the expansion valve working in conjunction with the' orank shaft governor. The piston rods are provided with tail ends, which, passing through cylinder tops, act as guides, and obviate the lashing which occurs with the machines /previously installed when the load is suddenly thrown on or off. Forced lubrication is adopted throughout by.means of.a system of pipes connected .to :a plungerpunip working from the H.P. eccentric strap, and delivering oil at a pressure between 10 to 201b. . A massive flywheel, woighing 9 tons, is mounted on the'shaft between, the engine and the dynamo, and a rack is ; provided on its periphery in order that the machine-can round when stesm. is. shut off, ■ by, a lover supported by a bracket 'to'tho fotindations. In connection with this turning gear, the makers have introduced a uscful.'dovice, intho shape of an adjustable* '' which can be screwed up agiinst the flywheel so as to prevent tho machine from turning. when undergoing overhaul. !When tested at tho engineTmakprs', works,.- in conjunction ..-with the dynamos, the steam consumption at full, load worked out at 181b. per kilowatt. Tho exhaust steam from the engine to a Korting'ejector- condenser,./ having .nozzles designed to pass 80,000 gallons of condensing water"per ihonr, and'jof."ample capacity: to a vacuum of 27- inches on full , load. The condensing water is supplied by a centrifugal .pump, : 'driven <by a 25 horse-power motor, at,, a speed Of 1100 revolutions per minute. ■' :'-' ■'j, ■:. ■ The largo . generator, which 'is . coupled direct to the engine) -was constructed,! by tho. Electric .Construction Company,; and has a.capacity of, 750 kilowatts at normal full load.' This machine,contains the,latest modifications in" design'; an ■ outstanding .feature being the .adoption of small electro-iriagncts, known as' "interpoles," between ■'.tho main poles. ;'■ The function of , theso additional poles, the windings''6n'which ca.rry. tho main ourrerit,. is to provide' a.' 'reversing" field, of such ..strength , as .to-nullify the electro-, motive 'force'of self-induction of'the armature coils:undergoing ; commutation,!,y.and : .th.u'e allow of tho machine running entirely /sparkless at all loads. -;Tho current is carried' frqjn tho machine to a' marble fitted, with -switch-gear' and ..■instnutientsj-pi, ample,capacity to dealwith'vthe.fpll.ioutput, ef the.generator;■.,!'.■..'■•' '.J' } : ; ~ jV#;'s 'V^'/'i