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C-Factor Testing. Hazen-Williams Formula. Pressure vs Elevation. Pressure Losses vs Distance. “Minor Losses”. Hydrant flow picture-0 flow. Hydrant flow medium rate. Hydrant flow-high rate. Pressure loss vs Flow Rate. Reynold’s Experiment. Sand roughness. PVC 1.5 X 10 exp (-3)
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Sand roughness • PVC 1.5 X 10 exp (-3) • Copper 3.05 X 10 exp(-2) • Steel 2.8 X 10 exp (-2) • Lined Cast .1 • Cast .2 • Concrete .3 • Cement .4
C factor • “A smoothness” coefficient • Higher C means Lower losses • Depends on material, finishing when new • Depends on material, age, chemistry, microbiology when old • Minor imperfections, scums, can have a great effect
C factor Depends on Diameter • Low diameters mean low c-factors • Small imperfections are meaningful • Turbulence is more widespread
C-Factors for 6” pipe • Unlined cast 125 • Lined Cast 133
Unlined cast 125 Lined cast 133 Scraped cst 116 Pigged cst 104 DICL 149 PVC 150 CPP 150 (Large dia) 70-90 NEW 30 years
Long piece of pipe • Dead ended so flow is in one direction • Known, Constant diameter • Minimum of valves, bends, tees, etc