TESTS OF DRAINAGE PUMPING PLANTS. 



27 



brate the meter, but the results obtained varied about 25 per cent, 

 showing that the water quantities measured are unreliable. Indica- 

 tor cards were taken on the high-pressure cylinder with an outside- 

 spring Tabor indicator. The thermometer on this cylinder showed 

 an average of 74.5° F. of superheat. The indicator used on the low- 

 pressure cylinder was an inside-spring Thompson. The thermometer 

 on this cylinder indicated an average of 49.2° F. of superheat. A 

 counter attached to the valve gear of the engine, read usually at 

 intervals of 10 minutes, gave the revolutions. The quantity of water 

 pumped was measured by two Pitot tubes inserted in the suction 

 pipes, traverses of the pipes being made at half-hour intervals. 

 Readings of the gages in the suction and discharge canals were taken 

 at half-hour intervals. Table 18 shows the results obtained during 

 the test, and figure 2 is a graph showing the efficiency of the plant 

 at various lifts. 



With the exception of the feed-water measurements the test was 

 satisfactory. The only irregularity was due to the presence of air 

 in the pump. As there was nothing to act as a flywheel except the 

 impeller of the pump, there was a tendency for the engine to change 

 speed rapidly on account of pockets of air in the water. This caused 

 considerable variation in the indicator card from the high-pressure 

 cylinder. Because of this variation six cycles were taken for each 

 card, and in this way a very close mean was obtained. 



Table 18.— Test of 



-inch unit of pumping plant No. 3, Avoca drainage district. Sept. 

 13-14, 1916. 





Boiler, 

 pressure. 



Speed. 



Indicated 

 horse- 

 power. 



Actual, 

 lift. 







Useful 

 water 

 horse- 

 power. 



Efficiency. 



Time. 



Discbarge. 



Pump, 

 piping. 



10.30 



11.00 



11.30 



12.00 



12.30 



J. 00 



I JO 



2.00 



sq. in. 

 14*; 

 152 

 151 

 153 

 148 

 146 

 149 

 141 

 151 

 152 

 138 

 156 

 146 

 161 

 ii- 

 l.:i 



/.'. />. in. 

 105.0 

 106. 1 

 106.0 



105. 9 



HI.",.!) 

 10.',. 'J 

 10.',. .'5 



105.0 

 106. i 

 105.4 

 105.8 

 105.8 

 10T>.9 

 105.0 

 105.4 

 105.2 



101.7 



188.83 



igo.68 



191. 65 

 187. 15 

 194.28 

 197.48 

 196. 75 

 200. 70 

 202. 45 

 208. 16 



202. 40 



214.90 

 214.85 

 216.75 

 216.86 

 21 & 15 

 246.00 

 266.03 

 266 i- 

 277, to 



Feet. 



2.22 

 2.19 

 2.36 

 2.46 

 2.60 

 2. 73 

 2.86 

 2.98 



Sec.-ft. 

 278. 35 

 276. 85 

 278. 08 

 275. 25 

 273. 20 

 272. 05 

 272. 85 

 272. 95 



G. p. m. 

 125,000 

 124, 100 

 124,900 

 123,500 

 122, 600 

 122, 1(H) 

 122,300 

 122, 500 



70.05 

 68.70 

 74.40 

 76. 45 

 80. 40 



84.20 



SS. 10 



92.20 



Per cent. Per cent. 

 37. 08 41. 1 

 36.02 ! 40.4 

 38.80 43.2 

 40.84 45.3 

 1 1 . 38 45. 9 

 42. 63 47. 3 

 44.92 49.9 

 45. s:i 51. 1 



3.00 



& 80 



LOO 



5.00 



(L00 .... 

 9.00 ..... 

 9.20 



3.48 

 3. 59 

 3. r,8 

 8. 96 

 •1. 16 

 1. 28 

 4.26 

 7. 08 

 7. 23 



200. 40 



207. 65 

 266. 05 



204. HO 



266.00 



202. 66 



269.60 



228. (K) 



217.28 



121,000 



120, loo 

 119,400 

 118,800 

 118,900 

 117,7. r ,0 

 116,600 

 102,300 

 97,700 



100.20 

 ION. SI) 



110.90 



US. HO 



12490 



125. SI 1 

 125. 30 

 1SI.I10 

 178.00 



51.03 



52. 43 

 51.61 



55. ■■<■' 

 57. 65 

 58.06 

 57. 20 



71. is 



56, 6 

 58. 2 



57. 3 

 81.4 

 64.0 



82. 3 



77.4 





10.-,. 2 



105. t 



74.4 



■ 



140 



7. 98 



104.60 



87,300 



175.90 





70.3 



