170 



THE IRKIGATION AGE. 



DISCHARGE PIPE AND SUCTION PIPE. 



The discharge pipe is 588 feet in length, 12-gauge 

 double ri vetted steel, with slip joints being used, with 

 an average diameter of 24 inches. In order that the 

 cost of freight be lessened, the pipe was made of prac- 

 tically equal lengths of 22, 24 and 26 inches diameter, 

 the two smaller sizes being nested for shipment inside 

 of the largest. By Cox's formula the friction head in 

 this pipe is found to be about 2 feet. 



For the suction pipe, 70 feet of 14-inch, 12-gauge 

 double rivetted steel is used, in which the friction head 

 is about 1 foot. The total friction head is therefore 3 

 feet, and the maximum head against which the pump 

 must operate 54 feet. A long suction pipe was occa- 

 sioned by the necessity of reaching far out into the 



minute, at which the capacity is 10 second-feet at 54- 

 feet head. The discharge is horizontal and under, and 

 size of pulley is 25x13. 



A 12-inch gate valve is placed on the discharge side 

 of the pump. The pump can be primed by means of 

 the boiler feed pump, or a steam ejector, the suction of 

 which is attached to the air vent on top of the centrifu- 

 gal pump, and the gate valve closed. After the pump 

 is full of water the engine is started, and after speed 

 is attained the gate valve is opened. This method of 

 priming is used only at the beginning of the season, or 

 when the tanks are empty, as after the pump is running 

 the water tanks may be filled by means of a valve and 

 pipe system connecting with the main discharge pipe 

 just beyond the gate valve, the same system serving to 



Vertical Section Through Engine Room of Elgin Plant. 



river when the water is low. A 15-inch foot valve is 

 attached to the end of the suction pipe. 



PUMP. 



A Byron Jackson horizontal centrifugal pump is 

 used, with an enclosed automatically balanced runner, 

 the diameter of suction and discharge being 12 inches. 

 In order that the silt and sand carried by the water 

 might not be injurious, three outboard double ring- 

 oiling bearings are used. It will be noted by the illus- 

 tration of the pump that there is a bearing upon each 

 side of the shell, the third being outside of the belt 

 pulley. The two stuffing boxes are entirely separate 

 from the bearings. The diameter of the runner is 24 

 inches, and the speed was fixed at 624 revolutions per 



supply priming water when required. A third means 

 of priming, and the one generally used, is by means of 

 a 3-inch by-pass. Water from the discharge pipe, which 

 is kept full when the pump is shut down over night by 

 closing the large gate valve, is by-passed around the 

 gate valve. This by-pass was installed in order to ob- 

 viate the danger of bursting the pump by the heavy 

 water hammer that might arise if it were primed by 

 opening the 'main gate valve. Strict orders are -given 

 that the main valve must not be opened until the pump 

 is full of water. 



ENGINE. 



The engine is a Chuse four-ported, self-oiling, high 

 speed automatic, size ISi/oxlS, with side crank. This 



