COOLGARDIE WATERWORKS

COOLGARDIE WATERWORKS

Pumping Through the Longest Main in the World.

西澳大利亚州的Coolgardie黄金田地距离海岸近363英里，于189a发现。1893年，匆忙开始了，由于几乎没有水，除了从浸泡和井中衍生出来，后来是政府坦克水库，或者通过矿山的盐水，以巨大的费用，疾病肆虐，铁路蒸馏出来夏季，部门必须每天支付5,000美元的机车供应。为了获取水，花岗岩范围无聊到3,000英尺的深度。因此，政府解决了从最近到海岸的水中，一部分或超过数英里的花岗岩范围为1,200英尺，而263个破碎的平原逐渐逐渐升至库尔加迪镇。因此，在1895年底，约翰·福雷斯特爵士（Sir John Forrest）爵士作为该地区最早的探险家之一，他知道在那里找到足够的供水供应是绝望的从海岸那里那里的淡水。The late C. Y. O’Connor, engineer-in-chief, was instructed to report as to the cost and the best method of carrying out the proposed scheme, and in July, 1896, he reported in favor of building a reservoir on the Helena river, near Mundaring in the Darling ranges, about twenty miles from Perth, the water to be then pumped through a main to Coolgardie. It the first place only 1,000,000 gallons was estimated as the probable requirement. This quantity was, however, increased to 5,600,000 gallons per twenty-four hours, and the estimated cost was set down at $12,500,000, exclusive of the reticulation of the towns on the way. Sir John Forrest introduced the necessary bill to the legislative assembly the following September authorising the raising of the money. After very strong opposition the bill was passed in September, 1898, after hearing the report of special commissioners, who visited all the principal waterworks and manufacturers of pumping machinery in Great Britain, the continent of Europe and the United States. Work was begun as soon after as possible. The main supply reservoir is in the Darling ranges, near Perth, 320 feet above sea-level, where two great arms of granite jut out across the narrow valley, at the bottom of which 'flows the Helena river. A gigantic dam of concrete is placed between these two granite arms, thus closing up one end of the valley. It is 760 feet long, and 100 feet high in the deepest part, and the foundations were carried down nearly too feet below the level of the river. At the base of the foundations the thickness of the dam varies from eighty-five to 120 feet, tapering to a width of fifteen feet on the top. Sixty thousand cubic yards of concrete were used in the construction. The surplus water flows over the crest of the dam. The reservoir or lake thus formed is eight miles long, and contains, when full, 4,600,000,000 gallons of exceptionally fine water. The catchment area consists of 850,000 acres, and consists chiefly of granite hills. At a trifling cost it would be possible to divert other streams into the reservoir, and so largely increase its capacity. Suitable valve towers are provided to regulate the flow to the first pumping station. The pipe used is the Mephan-Ferguson patent locking bar. It consists of two steel plates rolled into semi-circular form, the edges being upset by special machinery and a locking bar forced on. The joint is then finally clamped or closed by means of hydraulic machinery. The diameter of the Coolgardie pumping mains is thirty inches, each pipe being about twenty-eight feet in length, made of plates one-quarter-inch thick, and weighing about one and a quarter tons. In some sections, where extra pressure existed, the pipes were made of plates five-sixtcenths-inch thick. The total number of pipes required was about 60,000, and the thickness of two feet with soil, except where it ran through salt country, where, in order to avoid corrosion, the pipe was laid on trestles and protected from the sun by suitable coverings. No expansion joints were used or found necessary. The lead joints of the circumferential steel sleeves were made by a specially designed caulking machine, at first driven electrically, but latterly, owing to the extreme difficulty in getting water for the engine, worked by hand. The lead joint where the locking bar comes in was caulked up by means of a small hydraulic press. An average of from twenty to thirty joints per working day of eight hours was accomplished by the machines. The total contract price for the pipe (all Australian made) delivered was $5,125,000. This supply of 5,600,000 gallons every twenty-four hours, against a total estimated head (including friction) of 2,700 feet through a ,thirty-ix~ch pipe had to be pumped some o miles at a speed of about two feet per second. Hence, everything depended absolutely on the pumping machinery. From stations I to 4, in each station there are three complete sets of pumping machinery and boilers, any one of which is capable of .pumping o,ooo gallons per twen ty-four hours against a head of 450 feet. Two sets of engines and pumps are always pulping together into the main, one set is "spare. From stations 5 to 8 inclusive, there are at each station two sets of machinery, each set of machinery being capable of pumping ,6oo,ooo gallons per twenty-four hours against a head of feet, one set being `spare." Station No. i is close to the foot of the great dam on the Helena river. The water is raised 421 feet in daily work into an open concrete tank of a capacity of 468,000 gallons, situated at No. 2 station, the total distance from No. 1 being about one mile and a half. From station No. 2 the water is pumped up about 360 feet through twenty-three miles of main to the first regulating tank at Baker’s Hill —about 1,080 feet above sea-level. This tank is concrete, with a capacity of 500,000 gallons. The w'ater runs from Baker’s Hill by gravity to a second regulating, 500,000-gallon, concrete tank at Northam, eighteen miles farther on, the Northam tank, beingninety-four feet lower than Baker’s Hill. Still falling, the water reaches the great tank at Cunderin, whose capacity is 10,000,000 gallons, and is seventy-eight miles from the Helena reservoir. Stations 3 to 7 pump the water against a steady rise to the 8th station at Dedari, a distance of 217 miles from Cunderin, and situated at an elevation of 1,457 feet. Each station is provided with concrete tanks of 1,000,000 gallons capacity, which act as combined receiving and suction-tanks. From Dedari the water is pumped a distance of twelve miles to the main service reservoir at Bulla Bulling. This reservoir is of concrete reinforced with barbed wire strands. Its capacity is 12,000,000 gallons. Bulla Bulling supplies a small 1,000,000-gallon reservoir on Toorak Hill, overlooking the town of Coolgardie. The mean elevation is 1,working at stations Nos. 1 to 4 varies from 360 525 feet. The total head pumped against in daily feet to 410 feet, according as one or two engines are working. At stations Nos. 5 to 8 the head is from 180 to 210 feet. From Toorak tank the water runs by gravity to a reservoir on Mount Charlotte, w’hich is to supply the town of Kalgoorlie. In October, 1899, tenders for the pumping machinery were called for. That of Messrs. James Simpson & Co., Limited, of London was incepted, a special clause being inserted in the contract giving the firm permission to have half of the manufacturing done by the Worthington company. Their tender was by no means the lowest, but the proposals made by this company were of so complete a nature, and the design of engine offered—namely, the horizontal, high-duty, duplex, direct-acting Worthington engine—was guaranteed to give such highly economical results in working, that the government decided to pay the higher price asked for them, especially as it was well known that the Worthington company and Messrs. James Simpson & Co. had the greatest experience in the world of waterworks and pipe-line machinery. The government could not, and dare not risk a failure, and, therefore, wisely decided to give the work to two firms who held such a magnificent record, both for the character of their work and for their exceptional experience in the carrying out of pumping installations of the largest capacity throughout the world. Under this contract Messrs. James Simpson & Co. agreed to erect completely and have in full working order the whole of the pumping machinery, boilers, accessories, etc., within twenty-seven months after the signing of the contract. The size and type of engine selected was as follows, for stations Nos. i to 4 inclusive: Twelve triple-expansion, high-duty, Worthington pumping engines, each having two high-pressure cylinders, sixteen-inch; each having two intermediate-pressure cylinders, twentvfive-inch; two low-pressure cylinders, forty-six inch; two double-acting plungers, fifteen inch —all of a common stroke of thirty-six-inches. For stations Nos. 5 to 8 inclusive, eight engines of similar type; each having two high-pressure cylinders sixteen-inch; two intermediate-pressure cylinders, twenty-five-inch; two low-pressure cylinders, forty-six-inch; two double-acting plungers, twenty-one-inch — all of a common stroke of thirty-six-inch. The only difference in the whole of the engines is that eight of them had twenty-one-inch water-plungers and twelve had fifteen-irch. The whole of the steam ends are standard to one size. This means that the whole of the twenty boilers, accessories, etc, could be made standard, and the number of spare parts required to be held in store is greatly reduced. The boilers are Babcock & Wilcox, with single drums, and are equipped with superheaters. In the boiler house are feed water heaters and economisers, with all necessary accessories; one boiler being provided for each engine. The steam ends of each engine consist of two sixteen-inch high-pressure cylinders, two twenty-five-inch, intermediate-pressure cylinders, two forty-six-inch, low-pressure cylinders. All these are jacketed with steam at boiler pressure—namely, 175 pounds per square inch, the cylinder covers being jacketed as well. The estimated I. H. P. of each duplex engine may be taken at 300-If. P. The jackets are cast on the cylinders. The general arrangement of the rods is in accordance with the Worthington patents, the rods themselves being of the Vickers-Maxim oil-tougheoed steel turned and then ground to size. The steam valves are rotative, of the Corliss type, and are driven by the Worthington patent high-duty valve gear. Intermediate reheaters with steam at boiler pressure are used between the high-pressure cylinders and intermediate-pressure cylinders, and the intermediate-pressure cylinders and the low-pressure cylinders. The air pumps are placed immediately below and between the steam and water ends of the engine, and are driven by means of links and levers from the cross-heads. The water ends are of the Worthington outside-packed plunger type, fitted with steel air vessels on the delivery and cast iron air vessels on the suction. The suction and delivery-valves of the water ends are of the Worthington type with gun-metal seats, and the valves themselves are stamped out of the best manganese bronze. The condenser is placed in the suction, so that the whole of the water of the main passes through the condenser, and, as the volume is largely in excess of what is actually required, the temperature of the water in the main is not raised to any appreciable extent. It is well known that the efficiency of the Worthington high-duty engine is attained by the high-duty attachment with which it is provided; this also forms an ample safeguard in the event of the delivery main bursting ai any time. These engines have also been fitted with an automatic vacuum-breaking apparatus, so arranged that, when the pressure in the main falls below or rises above a prearranged limit, it immediately comes into action and opens a valve on the exhaust pipe to the atmosphere, and the engine stops immediately. The main pumps of each engine consist of two sets of double-acting plungers. working on the well-known Worthington cycle—i, e., ore set of pumps is always delivering into the main, with the result that the delivery is most uniform and shocks are entirely avoided, which makes this class of engine the most suitable for pumping through long lengths of main. The exhaust steam, on leaving the low-pressure cylinder, passes through an oil separator and thence to an auxiliary feed-water heater of the tubular type, then through the condenser and air pumps to the feed-water tank. As the steam passes from the jackets it is taken and used to drive the feed-pumps, which arc of the usual Worthington boiler pressure type. These feedpumps exhaust into the feed-water heater, and thus the feed-water is sent forward from the heater to the economiser at a very high temperature. Owing to the high temperature of the steam used.namely, 5,000 T'ahr. approximately. the whole of the piston rods and valve-spindles have been fitted with metallic packing. The cylinders, steam piping, and all parts liable to radiate beat are well covered with magnesia insulating material There is, also, the well-known Worthington high-duty attachment, by means of which the excess of power exerted by the steam in the cylinders at the beginning of the stroke is stored up and transmitted to the end of the stroke, when the steam pressure, owing to expansion, is smallest. The engine and boiler houses are of brick, and present a very fine appearance. Suitable overhead traveling cranes are provided, which can be operated from the floor of the engine house. The contract with the government was that each of the pumping engines should be capable of attaining throughout a twelve-hour trial a duty of 135,000,000 footpounds of effective work per 1,000.000 British thermal units supplied to the engine, which would not be returned to the boiler in the ordinary course of working; also that, to test the combined working duty of the pumping engines and boilers, two groups of machinery at one of the first four stations and one group of machinery at one of the second four stations should he capable of pumping through the main to the next reservoir not less than 2,800,000 imperial gallons of water during a twelve-hour trial; and that the combined duty of the group should throughout such trial amount to at least 135,000,000 footpounds of effective work for every 160 pounds of coal consumed, such coal being equal to a fair sample of good Collie (W. A.) coal having a calorific value of 10,000 British thermal units per pound. For the trials the government engineer selected a group of machinery at the No. 2 pumping station, and at the No. 8 pumping station. At the No. 2 pumping station the trial resulted in a duty of 142,093,598 foot-pounds of work being obtained per 1,000,000 British thermal units—showing a margin of 7,093,598 footpounds of work in favor of the engines. The working duty trial resulted in a duty of 144,427,000 foot-pounds of work being obtained for each 160 pounds of coal consumed—showing a margin of 9,427,000 foot-pounds in favor of the engines. The amount of water pumped during the twelve hours by the two groups of machinery was 2,998.081 gallons—being an excess of 198,081 gallons. At the No. 8 pumping station the trial resulted in a duty of 142,934,958 foot-pounds of work, being obtained per 1,000,000 British thermal units—showing a margin of 7,934,958 footpounds of work in favor of the engines. The working duty trial resulted in a duty of 148,141,000 foot-pounds of work being obtained for each 160 pounds of coal consumed—showing a margin of 13,141,000 foot-pounds in favor of tile engines. The quantity of water pumped by the engines during the twelve hours was 3,147,559 gallons—showing an excess of 347,559 gallons. It is estimated that some 30,000 tons of Collie coal per annum will be required when the plant is running the full twenty-four hours. The government has, therefore, put in railway sidings at each pumping station, af.d has erected coal bunkers under cover with a capacity of some 200 tons each. The trucks of coal are run on to an elevated timber gantry and the coal is then unloaded. The work was completed within the contract time, notwithstanding the fact that the engine sites were miles away from each other, and that every piece of machinery and all the supplies for the workmen and their camps and shops had to he carried such long distances. The work was carried on at the eight stations simultaneously.