| Show EQUIPMENT AT THE WARD SHAFT BY LEON M HALL the pumping plant just received at the I 1 ware ward shaft virginia city nevada is probably the largest best and most complete electrically driven mine pumping installation bior aver constructed so that a brief de of the same together with the reasons for its its existence may be of interest to those engaged in the mining and electrical industry the ward shaft association was formed some three years ago with the ostensible purpose in view of opening the ward shaft and of draining the middle group of mines on the comstock in order to explore this lode to its very lowest depths this shaft was originally sunk to a vertical depth of 2480 feet and just before reaching this point had passed through the vein which proved to be a mineralized fissure over sixty feet in width some fifteen years ago this shaft was abandoned on account of the stagnation then existing in the silver market and with the cessation of work it was allowed to decay and partially fill with rock and refuse of all kinds the shaft was rehabilitated and re timbered without much trouble to the 1600 foot level at which point a drainage drift was run feet to connect with the south lateral branch of the sutro tunnel below this level difficulties of all kinds incident to hot water and its attending evils were encountered and the progress has consequently been low and expensive today the shaft is in perfect condition to the 2430 foot level leaving but 50 feet of the old shaft to recover from the 2480 to the foot level the work will all be in new ground probably free from water so that it is confidently expected that progress will be rapid and the new electric pumps in early operation in reopening opening re this shaft a considerable flow of very hot water was encountered so that quite an extensive temporary pumping plant was necessary and this will be briefly described in the following on the 2100 foot level a knowles vertical triplex pump geared to a H P type C westinghouse induction motor was placed and arranged to take its water from a three step byron jackson centrifugal pump belted to a 50 horsepower westinghouse induction motor located on the 2330 foot level in turn this centrifugal receives its supply from a 9 blake sinking pump at the bottom of the shaft shaf t two horsepower ingersoll sergeant compound air compressors driven by two horsepower westinghouse motors are in operation on the surface and supply this sinker with the pec necessary essary motive power this temporary plant is raising gallons per minute afeei feet from the present pump to the sutro tunnel level in order to supplement this plant a five step byron jackson centrifugal pump directly connected t to a special westinghouse induction motor has been installed on the 2410 foot level this pump has a capacity of gallons per minute against 0 a head of feet and it will take its supply of water directly from the sinking pump thereby doing away with the triplex and centrifugal tri fugal pumps before mentioned this pump is entirely of bronze operates at 1700 r p in and under these conditions shows an efficiency of 67 per cent with the water temperature deg fahr this pump will be duplicated immediately for safety of operation and with these as an auxiliary the the company confidently hopes to reach the foot level at on distant day on the foot level the excavation of a pump station eighty feet long twenty four feet wide and twenty feet high is contemplated tem plated in which will be placed the per duplex electric power pump manent pumping plant the real subject of this sketch the capacity of this permanent installation will be U S gallons per minute against a total head of 1550 feet and this will be divided between two units each separately driven by a special slow speed horsepower westinghouse induction motor the pumps are of the knowles express type and are the embodiment of all of the best mechanical and electrical ideas obtainable tai for this class of work they are outside end packed duplex double acting pumps with plungers 6 1116 11 16 inches in diameter and 15 inch stroke the rotating element of the motor is placed directly on the crank shaft and they will operate at r p in the valves are automatic valves arranged in nests of fifteen each the valve area sq in is unusually large so that the consequent movement of the valves is extremely small all of which is conducive to a high speed with a minimum of wear the valves stuffing box glands and other vital parts exposed to the action of the water are of bronze and are arranged so that they may be readily renewed the plant will be equipped with a three stage electrically driven air compressor for charging the air receivers a vacuum pump and an automatic oiling system for convenience veni ence of erection and repair the pump station will be fitted with a 15 ton traveling crane in fact it is intended to include in this plant everything that will insure reliability and ease of operation the overall over all dimensions of each pump are 27 3 in length 17 in width and 14 W in height the motor is 13 in diameter and the steel crank shaft forged from one piece is 13 in diameter and 14 41 long the total cost complete for operation will be about these pumps pumps willbe will be supplied with either one of the two located in the sump at the bottom of the shaft and operated by seven ty five horsepower westinghouse motors on a vertical shaft the water will be discharged through 16 0 D steel column with welded steel flanges the thickness thickness of this pipe varies f from rom 14 A at the tunnel level to 9 16 at the bottom the column will be supported by means of heavy weight iron clamps 6 in length which in turn will rest upon the and end plates to resist the pressure of pounds to the square inch male and female flanges are used and each fitted with a lead filled copper gasket the electric current is taken down the shaft at 2240 volts over a three conductor lead covered steel armored cable ot of cm capacity the electric equipment from the automatic oil circuit breakers on the surface to the motors themselves is the best that money can buy so that once in operation with the splendid westinghouse plants of the truckee river general electric company behind it results are anticipated that have never before been approached pro ached for this class of work |
