LOSSES AT ELBOWS 



255 



Experiments by E. W. tichodrr 1 on right-angled bends having radii 

 from I'M to 20 pipe diameters, on a 6-inch wrought-iron pipe, give the 

 following approximate values for F. The resistance curves appear to 

 attain a minimum where R = 10 r ; rise to a maximum for R = 14 r ; 

 attain a second and lower minimum for R = 30 r ; and afterwards show- 

 increased values as II increases within the limits of the experiments. 



The general conclusion to be drawn from the foregoing results is that 

 11 should be about 30 r for minimum loss of head, while if circumstances 

 forbid the use of bends of such great radius, E should be between 5 and 

 10 r. Values of R less than 5 r, or between 10 r and 20 r, should be 

 avoided where possible. 



Loss of Head in Commercial Screw Pipe Elbows and Tees. Experiments 



Loss OF HEAD IN COMMERCIAL ELBOWS AND TEES. 



Proceedings American Society Civil Engineers," 1908, pp. 34, 416445. 



