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PUMP SELECTION PROCEDURE <br /> A. Determine pump capacity: <br /> END PERFORATION OF A PERFORATED LATERAL <br /> Gravity Distribution <br /> 1. Minimum suggested is 600 gallons per hour(10 gpm) to stay ahead of . ,,- --Oraes cover <br /> water use rate. ��``%``J <br /> ���� Topsoil �� \ <br /> 2. Maximum suggested for delivery to a drop box of a home system is 2,700 - • ... :..- yam of maloaf;1. Fa�ri� c�lam <br /> gallons per hour(45 gpm) to prevent build-up of pressure in drop box. Loamy Sand Layer r ...Inc„layer o1 hay or situs covered <br /> with red rode poser) <br /> 0r�•. Parforlotion Drilled Horizontally <br /> Pressure Distribution - into cap Near Top 2 q <br /> •.y/:Plus �1i Al Least 1 'to Edge <br /> 3. a. Select number of perforated laterals of Rock Layer <br /> .'Drain Field Rock:: .� <br /> .;. <br /> b. Select perforation spacing= ft. Perforations Located al <br /> c. Subtract 2 ft. from the rock layer length. clean Sand Lora Bottom of Lateral <br /> Racy Layer len -2 ft.= ft. .:g . <br /> y $t n Original Sod Properly Scarified <br /> Before Placing Sand Loyer <br /> d. Determine the number of spaces between perforations. <br /> Length perf.spacing= 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 /> get total number of perforations. yin I/r <br /> Iaterala X per„ ,eras= perforations. <br /> 1.0a 0.56 0.74 <br /> 15 0.69 0.90 <br /> g. pia X gpm= gpm. 2.0b 0.80 1.04 <br /> �( gpm 4.0 11.1133 2.5 0.89 1.17 <br /> SELECTED PUMP CAPACITY `T5 3.0 0.981.28 <br /> I.47 <br /> 5.0 1.26 1.65 <br /> B.Determine head requirements: 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 /> (3 feet <br /> 2. If pumping to a pressure distribution system,add five feet for pressure <br /> required at manifold <br /> 5 feet <br /> 3. Friction lossPipe Length <br /> I I' <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.= 5 28 ft./100 ft of pipe Elevation Difference <br /> b. Determine total pipe length from pump to discharge • Pump <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 /> 3 S x 1.25 = 44feet gpm Friction lass per 100 R of pipe <br /> c. Calculate total friction loss by multiplying 10 0.69 0.20 <br /> friction loss in ft/100 ft by equivalent joipe length. 12 0.96 0.28 <br /> Total friction loss= 4"a\-- x 3,2 i +100= feet 14 1.28 0.38 <br /> 4. Total head required is the sum of elevation difference, 16 1.63 0.4818 2.03 0.60 <br /> special head requirements,and total friction loss. • <br /> - 20 2.47 0.73 0.11 <br /> 25 3.73 1.11 . 0.16 <br /> 13 + 5 + 2.- 30 5.23 1.55 : 0.23 <br /> 35 7.90 2.06 • 0.30 <br /> (1) (2) (3c) 40 11.07 2.64 0.39 <br /> 45 14.73 3.28._ 0.48 <br /> TOTAL HEAD Z-C) 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 />