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PUMP SELECTION PROCEDURE <br /> A. Determine pump capacity: <br /> Gravity Distribution END PERFORATION OF A PERFORATED LATERAL <br /> 1. Minimum suggested is 600 gallons per hour(10 gpm)to stay ahead of Gran Cover <br /> water use rate. <br /> •;: Topsoil °�'a,, <br /> 2. Maximum suggested for delivery to a drop box of a home system is 2,700 ,,;; .,:Layer of Geot.:tiie Fabric(or four- <br /> .: . <br /> gallons per hour(45 gpm)to prevent build-up of pressure in drop box. Loamy Sand Layer Inch layer of hay or snow covered <br /> . - - .-with red rosin paper) <br /> 112"4177. inriENIIIMIl•. Perforation Drilled Horizontally <br /> Pressure Distribution <br /> R ... Into •p Near Top <br /> - !` Al Least le to Eclat3. a. Select number of perforated laterals y t()),4-ph,.Pius Field Rock, •'�• of Rock Layer <br /> b. Select perforation spacing= ) ft. Pe er <br /> rforotlans Located or <br /> c. Subtract 2 ft.from thehrock layer length. peon sand Layer Bottom of La,erai <br /> Rock layer length-2 ft .=Sl ft. 1 :..; a:- `� .-0- .. <br /> rlabinal Soil Properly Scarified <br /> Before Placing Sand Layer <br /> d. Determine the number of spaces between perforations. <br /> Length perf.spacing= .f c./ ft.+ '? ft.= 1 c1 spaces <br /> TABLE OF PERFORATION DISCHARGES IN GPM <br /> e. 19 spaces+ 1 = :1.O perforations/lateral <br /> f. Multiply perforations per lateral by number of laterals to Head Perforation diameter(inches) <br /> get total number of perforations. 7/ 1/ <br /> �„e x -A9,-,-.,. sea perforations. <br /> 1.0a 0.56 0.74 <br /> 1.5 0.69 0.90 <br /> g. p�er-O. x a = y S gpm• 2.Ob 0.80 1.04 <br /> 2.5 0.89 1.17 <br /> SELECTED PUMP CAPACITY 1 gpm 4.0 1.113 1.47 <br /> I-4 `( <br /> 5.0 1.26 1.65 <br /> B.Determine head requirements: <br /> aUse 1.0 foot of head for residential systems. <br /> 1. Elevation difference between pump and point of discharge. bUse 2.0 feet of head for other establishments <br /> 1 a feet <br /> 2. If pumping to a pressure distribution system,add five feet for pressure <br /> required at manifold <br /> . .. feet <br /> 3. Friction loss Pipe Length + <br /> a. Enter friction loss table with gpm and pipe diameter. Point of Discharge <br /> Read friction loss in feet per 100 feet from table. 1,c..0 <br /> F.L.= 3.a.4( ft./100 ft of pipe Elevation Difference <br /> b. Determine total pipe length from pump to discharge Pump IN.t) <br /> point. Add 25 percent to pipe length for fitting <br /> loss,or use a fitting loss chart. Equivalent pipe F-18b <br /> length-1.25 times pipe length= 1.5 inch 2.0 inch 3.0 inch <br /> I LD x 1.25= a.0 0 feet gpm Friction lou per 100 ft of pipe <br /> c. Calculate total friction loss by multiplying 10 0.69 0.20 <br /> friction loss in ft/100 ft by equivalent pipe length. 12 0.96 0.28 <br /> Total friction loss= 3e.R`d x 2,(.)O +100. '1 feet 14 1.28 0.38 <br /> 4. Total head required is the sum of elevation difference, 16 1.63 0.48 <br /> special1head requirements,and total friction loss. 20 2.03 0.60 <br /> q 20 2.47 0.73 0.11 <br /> 25 3.73 1.11 0.16 <br /> a + S' + / 30 5.23 1.55 0.23 <br /> (1) (2) (3c) 35 7.90 2.06 0.30 <br /> 40 11.07 2.64 0.39 <br /> 45 14.73_ ._3. L 0.48 <br /> TOTAL HEAD a`'I feet 50 3.99 0.58 <br /> 55 4.76 0.70 <br /> 60 5.60 0.82 <br /> C. Pump selection <br /> 1. A pump must be selected to deliver at least Li s',gpm (Step A) <br /> with at least ay feet of total head (Step B). <br />