20 



BULLETIN 1067, U. S. DEPARTMENT OF AGRICULTURE. 



the useful water horsepower. The indicated horsepower of the 

 engines and the total head on the pump were then obtained in the 

 usual manner. The loss of velocity head due to lack of proper 

 enlarging of the ends of the pipes is quite plainly shown. As this 

 loss varies with the square of the velocity of the water, it is greatest 

 when the pump is working at maximum capacity. 



The water used during the boiler test was measured by means of a 

 Worthington piston-type water meter, afterwards calibrated. The 

 steam used for all purposes per horsepower per hour was 54.91 

 pounds. Table 12 shows the results of the test. 



Table 12. — Test of pumping plant in subdistrict No. 3, Lafourche drainage district 

 No. 12, Raceland, La., Nov. 14, 1913. 



UNIT NO. l. 



Time. 



Boiler 

 pres- 

 sure. 



Speed. 



Indi- 

 cated 

 horse- 

 power. 



Actual 

 lift. 



Head 



on 

 pump. 







Useful 

 water 

 horse- 

 power. 



Efficiencies. 1 





1 



2 



3 



9.00 



9.30 



10.00 



10.30 



11.00 



11.30 



12.00 



12.30 



1.00 



100 

 104 

 101 

 102 

 103 

 103 

 106 

 104 

 84 



R.p.m. 

 142 

 143 

 140 

 144 

 144 

 147 

 146 

 142 

 134 



48.4 

 48.4 

 46.2 

 48.9 

 46.8 

 49.8 

 49.1 

 48.1 

 39.8 



Feet. 

 1.45 

 1.70 

 1.95 

 2.20 

 2.40 

 2.75 

 3.00 

 3.35 

 3.62 



Feet. 

 2.17 

 2.67 

 2.68 

 2.76 

 2.98 

 3.32 

 3.74 

 4.23 

 4.20 



Sec.-ft. 

 58.18 

 58.28 

 54. 89 

 54.84 

 54.16 

 54.11 

 51.60 

 49.44 

 42.13 



G. p. m. 

 26,100 

 26, 160 

 24,630 

 24, 610 

 24,290 

 24,280 

 23,150 

 22, 200 

 18, 910 



9.57 

 11.25 

 12.14 

 13.69 

 14.76 

 16.89 

 17.57 

 18.80 

 17.31 



Per ct. 

 20.0 

 23.2 

 26.3 

 28.0 

 31.5 

 33.9 

 35.8 

 39.1 

 43.6 



Per ct. 

 22.2 

 25.8 

 29.2 

 31.1 

 35.0 

 37.7 

 39.8 

 43.4 

 48.4 



Per ct. 

 33.2 

 40.5 

 40.1 

 39.0 

 43.5 

 45.5 

 49.5 

 55.0 

 56.2 



Average . . 



100.8 



142. 3 47. 3 



2.39 



3.19 



53.07 



23,820 



14.55 



















UNIT NO. 2. 



9.00 



100 



150 



88.4 



1.45^ 



3.24 



66.97 



29, 900 



11.01 



12.5 



13.9 



31.0 



9.30 



104 



124 



51,6 



1.70 



3.05 



61.08 



27, 290 



11.80 



23.0 



25.6 



46.0 



10.00 



104 



124 



51.1 



1.95 



3.30 



60.54 



27, 030 



13.41 



26.2 



29.2 



49.3 



10.30 



102 



128 



53.4 



2.20 



3.43 



59.80 



26, 720 



14.92 



27.9 



31.0 



47.2 



11.00 



101 



127 



53.2 



2.40 



3.52 



58.28 



26,050 



15.86 



29.8 



33.1 



48.5 



11.30 



103 



127 



53.0 



2.75 



3.77 



56.66 



25,310 



17.67 



33.3 



37.0 



50.7 



12.00 



104 



126 



52.8 



3.00 



3.95 



55.24 



24,690 



18.79 



35.6 



39.5 



52.0 



12.30 



104 



124 



48.3 



3.35 



4.24 



53.67 



23,810 



20.39 



42.2 



46.9 



59.4 



1.00 



84 



120 



41.7 



3.62 



4.32 



43.65 



19,500 



17.92 



43.0 



47.8 



57.0 



1.30 



102 



126 



50.8 



3.90 



4.70 



41.54 



18, 570 



18.37 



36.2 



40.2 



48.5 



2. 00 



108 



128 



52.1 



4.00 



4.97 



47.14 



21, 060 



21.38 



41.1 



45.7 



56.6 



Average. . 



101.5 



127.6 



54.2 



2.76 



3.86 



55.00 



24,680 



16.50 















1 Efficiencies: 



1. Efficiency of engine, pump, and piping. 



2. Efficiency of pump and piping, assuming mechanical efficiency of engine at 90 per cent. 



3. Efficiency of pump, assuming mechanical efficiency of engine at 90 per cent. 



As the lift of the pumps was so variable, no average efficiency was 

 determined. A summary of the boiler test follows: 



Boiler test. 



Duration of test, hours '. . 5. 08 



Total water used, pounds 26, 760 



Total fuel oil used, pounds 2, 095 



Ratio of water to fuel oil 12. 7 



Average steam pressure, pounds per square inch 101 



Average feed-water temperature, ° F 144 



Factor of evaporation 1. 11 



Ratio of water evaporated at 212° to fuel oil 14. 1 



Efficiency of boiler (assuming 18,500 B. T. U. per pound of fuel oil), per cent. 74 



