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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 Gross cover <br /> water use rate. Topsail ` <br /> 2. Maximum suggested for delivery to a drop box of a home system is 2,700 . <br /> gallons per hour(45 gpm)to prevent build-up of pressure in drop box. Loam sand �I or c`a'e"i'`F°°ric(«'"`' <br /> Y Yer oyer of hay«flraw covered <br /> -with red rain paper) <br /> r waittl LaWPerWofalwaitionOrll led Horironlolly <br /> Pressure Distribution <br /> Nlo p Near Top <br /> 3. a. Select number ofrforated laterals 3 '� Plaf At Leaf' 12'to Edge <br /> I' 3/4" F4-4 Rac:..Y;:. ..:__...:.:.... of Rock Layer <br /> b. Select perforation spacing= 3 ft. P.rr«ouaa.Located of <br /> c. Subtract 2 ft.from the rock layer length. cNaa sane Laver Bottom of Lateral <br /> -2 ft.= "aC ft. <br /> orlglnol sou Properly Scarified <br /> Before Placing Sand Layer <br /> d. Determine the number of spaces between perforations. <br /> Length perf.spacing= lc�L ft.+ ft:_ _spaces TABLE OF PERFORATION DISCHARGES IN GPM <br /> e. _�_spaces+1 perforations/lateral <br /> f. Multiply perforations per lateral by number of laterals to Head Perforation diameter(inches) <br /> t total number of perforations. <br /> x )_�:perforations. 7/32 t�' <br /> 1.0a 0.56 0.74 <br /> q_) r)L,l is 0.69 0.90 <br /> $• perfe x 6P'^ P__fper(_ gpm. 2.Ob 0.80 1.04 <br /> 2.5 0.89 1.17 <br /> SELECTED PUMP CAPACITY ? 3.0 0.98 1.28 <br /> $1'm 4.0 1.13 1.47 <br /> 5.0 1 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 /> feet <br /> 2. If pumping to a pressure distribution system,add five feet for pressure <br /> required at manifold <br /> ,17 -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. <br /> F.L. = I, . , ft./100 ft of pipeElevation Difference <br /> b. Determine total pipe length from pump to discharge 1:1-pu'' <br /> mp ✓_ - <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 /> Ll to x 1.25 = feet gpm Friction loss 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= x /, +100= feet 14 1.28 0.38 <br /> 4. Total head required is the sum of elevation difference, 16 1.63 0.48 <br /> 18 2.03 0.60 <br /> special head requirements,and total friction lass. ''0 2.47 0.73 0.11 <br /> 25 3.73 1.11 0.16 <br /> + + _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 3.28 0.48 <br /> TOTAL HEAD _ 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 gpm (Step A) <br /> with at least.��feet of total head (Step B). <br />