28 



BULLETIN 1067, TJ. S. DEPARTMENT OF AGRICULTURE. 



TEST OF PUMPING PLANT NO. 2, OF AVOCA DRAINAGE DISTRICT, ST. MARY PARISH, LA. 



DESCRIPTION OF PLANT. 



The equipment of this plant consists of a cross-drum boiler with 

 1,162 square feet of heating surface, and a Corliss compound conden- 

 sing engine with cylinder diameters 10 inches and 20 inches and 30- 

 inch stroke with drop cut-off, direct connected to a double-suction 

 centrifugal drainage pump. The pump has a discharge pipe 48 

 inches in diameter and suction pipes 36 inches in diameter, all pipes 

 measured at the flange. Both the suction and discharge pipes are 

 enlarged at their outer ends. 



The test was made with the plant in normal operation. The in- 

 struments and methods were the same as those used in the test of 

 pumping plant No. 3 of Avoca drainage district. The average tem- 

 peratures observed in degrees F. were as follows: Feed water 198°, 

 air 99°, oil 93°, water pumped 80°. The weight of fuel oil used in 2'J 

 hours was 934 pounds. The rate of use was quite regular, and the 

 best economy was shown near the end of the test. Friction cards 

 were taken at the end of the test with no water in the pump. The 

 results are given in Table 19. 



Table 19. 



Revolu- 

 tions per 

 minute. 



Indicated 

 horse- 

 power. 



84 

 101 

 110 



8.32 

 11.01 

 13.64 



Table 20 gives the results obtained during the test. 



Table 20. — Test of pumping plant No. 2, Avoca drainage district. 



Time. 



Boiler 

 pressure. 



Speed. 



Indi- 

 cated 

 horse- 

 power. 



Actual 

 lift. 



Discharge. 



Useful 

 water 

 horse- 

 power. 



Effi- 

 ciency: 

 Pump, 

 engine, 



and 

 piping. 



2.00 



Lbs. per 

 sq. in. 

 115 

 130 

 135 

 127 

 127 



R. p. m. 

 101.6 

 113.8 

 118.8 

 111.3 

 111.6 

 112.0 

 108.6 



123.75 



125. 35 

 170. 50 

 149. 63 

 150.78 

 118.95 

 116.69 



Feet. 

 2.76 

 2.81 

 3.41 

 4.45 

 4.93 

 5.84 

 6.21 



Sec.-ft. 

 141. 30 

 138. 35 

 139. 25 

 133. 73 

 127. 63 

 110.72 

 99.81 



G. p. m. 

 63, 400 

 62, 100 

 62, 500 

 60, 000 

 57,300 

 49, 700 

 44,800 



44.2 

 44.0 

 53.8 

 67.4 

 71.3 

 73.2 

 70.3 



Per cent. 

 35.70 



2.30 



35.10 



3.00 



31.54 



3.40 



45.00 



4.05 



47.30 



4.19 



61.56 



4.30 



142 



60.21 







