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PUMP SELECTION PROCEDURE Perforation Discharges in gpm A. Determine pump capacity: perforation diameter gravity distribution head (inches) Minimum required discharge is 10 gpm (feet) 1/8* 3/16 7/32 1/4 2.Maximum suggested discharge is 45 gpm 1.Oa 0.18 0.42 0.56 0.74 pressure distribution 2.Ob 0.26 0.59 0.80 1.04 see pressure design worksheeet 5.0 0.41 0.94 1.26 1.65 Selected pump capacity: Lo 2- gpm a Use 1.0 foot for single-family homes. b Use 2.0 feet for anything else. " Potential for plugging B. Determine head requirements: 1.Elevation difference between pump and point of discharge. 10 feet 2. Special head requirement: If pumping to a pressure distribution system,five feet for pressure required at manifold.If gravity system,zero. 5 feet soil treatment 3. Friction loss - system ;49191.¢4. of a. Enter friction loss table with gpm and pipe diameter. iengtsipe Read friction loss in feet per 100 feet from table. Inlet ' oNa,r,,..,.. e elevation difference F.L. = ,0 ft./100 ft of pipe pipe b. Determine total pipe length from pump to discharger4, y' C6 2 point. Estimate by adding 25 percent to pipe length for fitting loss. Equivalent pipe length times 1.25 =total pipe length (o D x 1.25 = 7 J feet c. Calculate total friction loss by multiplying friction loss Friction Loss in Plastic Pipe in ft/100 ft by equivalent pipe length. Per 100 feet Total friction loss= a ). 0 x '?st.- =100= I to feetnominal pipe diameter 4.Total head required is the sum of elevation difference,special head flowrate1.5" 2" 3" requirements,and total friction loss. 20 2.47 0.73 0.11 v + + Co/ (1) (2) (3c) .? 4 1 11 0:16. Total head: 3 ) feet 30 5.23 1.55 0.23 35 6.96 2.06 0.30 iajnM 2.64 0.39 45 11.07 3.28 0.48 C. Pump selection 50 13.46 3.99 0.58 Y.'Z4.76' . 0.70 1. A pump must be selected to deliver at least (oZgpm 60 zO.0 5.60 0.82 (Step A)with at least 3) feet of total head (Step B). 65 6.48 0.95 70 7.44 1.09