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500 K.W. Westinghouse, Parsons Turbine, No. 209. From tests by Messrs. Ludwig & Co., Engineers, Atlanta. Test No. (1 hour each).
(A) lbs. per brake horse power hour, 14.92, 14.05, 13.68, 12.22, 14.91, 15.08, 15.86.
Steam consumption :
15.7, 14.8, 14.8, 12.7, at 150° Superheat
Better than guarantee % 5.5, 5.1, 6.08.
(A) Uncorrected for moisture.
(B) Corrected for low vacuum on full load test.
This gives results of the previously mentioned 500 kilowatt turbine tested under various conditions. Note that these results are uncorrected for moisture in the steam and especially the good results on low vacuum and the safe amount by which it bettered the contract guarantee.
Test on Mill Plant. Quite recently results of a commercial test upon an actual cotton mill installation were obtained and are presented in Table 3. The coal was of good quality, but contained a large percentage of moisture, as it was hauled during a rain storm. No allowance has been made in the weights for this moisture. The condensed steam was measured by meter and checked by weighing. Considering such a small plant running at less than two-thirds rating, a steam consump
tion of 25 pounds per kilowatt hour, or 2.5 pounds of coal per kilowatt hour, including auxiliaries, is good economy, and especially when the small opportunity for variable economy in the turbine is considered.
Table No. III.
TEST OF COTTON MILL TURBINE PLANT.
500 K.W. Westinghouse Parsons Turbine. Duration of Test 6.30 A. M., 6 P. M., 11 hr.
Kind of coal (weighed and fired wet) New River, Bituminous.
Summary. Before closing the subject, it would be well to take a general survey of the turbine situation as outlined above in detail, keeping prominently in mind the three important factors selected at the outset as the basis of our inquiry, and the advantages of this type of prime mover for textile work.
First, we have a machine that is entirely self-contained, and whose operation is not continually jeopardized by the danger of injury to independent auxiliaries.
Second, one that may be dismantled and re-assembled for service within an hour; in which only the covers of bearings and cylinder need be removed in order to lift out the entire rotor, instead of going through the laborious process of dismantling piece by piece a built-up structure.
Third, a natural force, capillary attraction, supports the rotor weight without forced lubrication or wear; not an artificial means in which the turbine has no control over its supply of oil, and only a few moments intervene between success and failure. Only this has made it possible for a Parsons turbine to run 17,200 hours without stopping.
Fourth, a generator protected from heat radiated from a turbine, steam leakage from glands, oil drip from bearings and variation in room temperature; one that is noiseless in operation and positive in ventilation, all of which insure long life.
Fifth, a system of steam distribution in which the mechanical difficulties of high velocity have been overcome by simple, subdivided expansion, entirely avoiding wear on moving or stationary blades; with a blade construction possessing ample resistance to stress and chemical action, yet capable of relieving locally any emergency condition arising from excessive temperature strains or other causes.
Sixth, we have a prime mover sensitive in speed variation to an unprecedented degree, one per cent. or less within normal ranges of cotton mill load, which insures a maximum production and always under the instantaneous control of the governor, not controlled in successive steps, requiring the turbine to "straddle” the load, as it were.
Seventh, by the addition of a single valve, we have provided. enormous forcing capacity entirely beyond the range of a belt or rope drive, which will enable us to "pull through" what would otherwise constitute a serious emergency.
Eighth, once proven in shop economy tests, we have a standard for future comparison; with adjustments locked in norma! working position, the economy should remain unchanged except through actual damage; and with the economies of small units. so close to those of larger ones, it is possible to sub-divide power into several units a most valuable security against manufacturing interruptions.
Ninth, with the extreme compactness indicated by the accompanying curve, Figure 20, we have reduced not only floor space and head room, but also general construction costs and fixed charges thereon. This offers a very attractive feature in that turbines may frequently be used in existing power houses to care for an increased demand for power. I have in mind a cotton mill where a 1500 kilowatt turbine unit has been erected on one-half of existing foundation of a 1200 horse power cross compound engine, there being sufficient space left to erect another unit of a similar size, giving a total of 4000 horse power capacity on a foundation formerly required for 1200 horse power. Condensers, either surface or jet, are being installed beneath the turbine in the foundation, thus eliminating all bends in the exhaust piping and extra space for auxiliaries. In the Fort Wayne Central Station, turbines are located on the second floor of the power house, supported only by latticed columns.
Tenth, and finally, the whole subject of the comparative advantages or disadvantages of the steam turbine is well brought home by this fact: that two 500 kilowatt turbine units were put in operation at the power house of the Cleveland Electric Illuminating Company, 743 hours and 47 hours, respespectively, from the time the machines left the shops at East Pittsburg. The last machine was actually erected in 13 hours straight work.
It is hoped that the above features will serve in a measure to
explain the construction and operation of the Westinghouse, Parsons Turbine Unit, and also indicate the advantages accruing from the use of this type of prime mover, as applied to the textile industry.
The PRESIDENT. Does anyone wish to ask any questions? I am sure Mr. MERRILL will be very glad to answer anything that comes within the scope of his paper if he can.
[There were no questions.]
REPORT OF COMMITTEE ON NOMINATIONS.
I understand that the chairman of the committee on nominations is absent and I will ask the Secretary to read his report.
The SECRETARY. Mr. J. R. MONTGOMERY, the chairman of the committee on nominations, gave me the report, which is as follows:
To the National Association of Cotton Manufacturers:
The committee on nominations have attended to the duty assigned them and report the following nominations:
CHARLES T. PLUNKETT, Adams, Mass.
GEORGE OTIS DRAPER, HOPEDALE, MASS.
DIRECTORS FOR THREE YEARS.
ROBERT BEATTY, PHILADELPHIA, PA.
DIRECTOR FOR ONE YEAR.
DAVID S. JOHNSTON, COHOes, N. Y.
J. R. MONTGOMERY,
Chairman for the Committee.