492 



AGRICULTURAL ENGINEERING 



5 gallons per minute, which would require the use of pipe at 

 least 1 inch in diameter or larger for mains, and the smaller 

 sizes should only be used for branches. In many cases the 

 pump is overloaded by using pipe of insufficient size. 



Flow of water in pipes. 



Flow in gallons per minute 



Head in feet lost by friction in each 100 foot of length 





^2-inch pipe. 



1-inch pipe. 



0.5 

 1.0 

 2.0 

 4.0 

 10.0 



4 



7 



17 



54 



224 



.03 

 .07 



1.6 



5.3 



9.3 



Piping Systems. There are two general types of under- 

 ground piping systems on farms. The first of these is known 

 as the " ramified " system, which consists of a main laid in the 

 shortest possible line from the water supply to the farthest 

 hydrant, with branches extending out on either side like 

 branches of a tree. The one objection to this arrangement 

 is that the water in the branches is dead unless constantly in 

 use. There is, however, a saving in the cost of pipe, as 

 smaller sizes may be used for the branches. The second type 

 is known as the " circulatory " system, in which the main pipe 

 passes to all hydrants and the extreme ends are connected, if 

 possible. With this system the water does not stagnate in 

 any part. 



In planning the distributing system, it is best to provide 

 large mains if fire protection is desired. Valves should be 

 put in various parts so that a disturbance in one part will not 

 interfere with the use of the rest of the system. Often it 

 can be arranged to have the fresh water, as pumped, pass 

 through the house, thus providing drinking water. 



