16 



BULLETIN 1067, U. S. DEPARTMENT OF AGRICULTURE. 



usual oil and boiler feed pumps. The machinery is housed in a 

 corrugated-iron building and is mounted on a concrete foundation 

 supported by piling. 



The pumps take the water from the main canal of the district and 

 discharge it into Bayou Des Allemands through about 300 feet of 

 outlet canal. The bulk of the water from the average rain is lifted 

 about 3 feet, so the plant was tested at this lift. When the canals 

 are empty the lift is about 8 feet, but very little water is lifted more 

 than 5 feet. The water on the discharge side varies about 1 foot in 

 height, according to the stage of water in the bayou. 



FIRST TEST. 



For the first test the plant was operated under normal conditions, 

 using only one of the boilers. Observations were taken at intervals 

 of a half hour. The discharge from the pumps was measured by 

 means of a Pitot tube in each discharge pipe. Gages set in the still 

 water in the suction and discharge canals were read and the actual 

 lift obtained. This lift was used in computing the water horsepower. 



The water used in the boiler during the test was measured in a 

 large storage tank. Water was then drawn from this tank and 

 pumped through the heater into the boiler. The oil used as fuel 

 during the test was measured with approximate accuracy in the 

 large storage tank. However, as the tank was about 19 feet in 

 diamater and the oil was lowered only 0.091 foot during the test, 

 it is evident that the oil measurement is only a close estimate, and 

 the error of observation might change the result materially. 



The usual method of finding the total head on pump, or dynamic 

 head, was followed, but gave results so erratic that they were con- 

 sidered of no value. The results obtained are set forth in some 

 detail in Table 9. A summary of results is given in Table 8. 



Table 8. — Engine and pump test. 



Unit No. 1. ! Unit No. 2. 



Duration of test, hours 



Revolutions per minute 



Indicated horsepower 



Steam used per indicated horsepower, per hour, average pounds 



Discharge, cubic feet per second 



Discharge, gallons per minute , 



Static head, feet : 



Useful water horsepower 



Efficiency of pump, eneine, and piping -. 



Efficiency of pump and piping (assumed engine efficiency, 90 per cent) 



BOILEK TEST. 



Duration of test, hours 



Average steam pressure, pounds per square inch 



Total water used, pounds 



Total fuel oil used, pounds 



Ratio of water to fuel oil 



Average feed-water temperature, °F 



Factor of evaporation 



Ratio water evaporated from and at 212° to fuel oil 



Efficiency of boilers (assuming 18,500 B. t. u. per pound of oil), per cent 



4 



4 



172 



162 



46.8 



38.7 



40.7 



40.7 



38.7 



37 



17,340 



16, 580 



2.97 



2.97 



13. 01 1 



11.34 



28 



29.3 



31.1 



32.6 



4.2 





89. 01 . 





14, 611 





1, 507 



9.69 





1.097 . 





10. 63 . 





55. 6 . 





