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) <br />_) <br />PUMP SELECTION PROCEDURE <br />A-Determine pump capacity. <br />Gravity Distribution <br />1. Minimum suggested is 600 gallons per hour (10 gpm) to stay ahead of <br />water use rate. <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. <br />Pressure Distibution <br />3. a. <br />b. <br />c. <br />d. <br />Select number of perforated laterals :3 <br />Select perforation spacing= ..3 feet. <br />Subtract 2 ft. from the rock layer length. <br />i<.od,.~~ -2 ft.-!rd, feet. . <br />Determine the number of spaces between perforations. <br />Length perf. spacing= _ku.. ft. + _3_ ft. = 2.,.;l__ spaces <br />~spaces+ 1 =~perforations/lateral e. <br />f. Multiply perforations per lateral bY. number of laterals to ?f.p''"Oi A-. <br />get total number of perforations. 2-; x ;.}.;Liien1 = -1:.!..!.z.. perforations. <br />lA, x • '? IP_, = .:f:::L gpm. g. 7'l!l'S ,;;,a<J,-• <br />SELECTED PUMP CAPACITY :::S'o/ gpm <br />B. Determine head requirements: <br />1. Elevation difference between pump and point of discharge. <br />1 feet <br />2. If pumping to a pressure distribution system, five feet for pressure <br />3. <br />4. <br />required at manifold if gravity 3YStem, zero. <br />_..;:S=---feet <br />Friction loss <br />a. Enter friction loss table with gprn and pipe diameter. <br />Read friction loss in feet per 100 feet from table. <br />F.L = ') 1 la ft./100 ft of pipe <br />b. Determine total pipe length from pump to discharge <br />point. Add 25 percent to pipe length for fitting <br />loss, or use a fitting loss chart. Equivalent pipe <br />length -1.25 times pipe length = <br />/a Q x 1.25 = )Su feet <br />c. Calculate total friction loss by multiplying <br />friction loss in ft/100 ft by equivalent pipe length. <br />Totalfrictionloss= :J.(.., x JS'() +100= '-I <br />Total head required is the sum of elevation difference, <br />special head requirements, and total friction loss. <br />,S::: + If __ J_,__+ <br />(1) (2) (3c) <br />TOTAL HEAD / k, feet <br />C. Pu.mp selection <br />1. A pump must be selected to deliver at least <br />feet <br />~ gpm (Step A) with at least _J_Ja_ feet of total head (Step B). <br />F-17 <br />DO PERFORATION Cf" A PERFORATED LATERAL <br />Required Perforation Disch~e <br />in gallons per minute (gpm <br />Discharge <br />Head ~2 md>paf ¼ mdopaf <br />(feet) <br />1.0a 0.56 0.74 <br />2.0b 0.80 1.04 <br />a. Use for single family homes <br />b. Use for all other applications <br />gpm <br />10 <br />12 <br />14 <br />16 <br />18 <br />20 <br />25 <br />30 <br />35 <br />_40 __ <br />45 <br />50 <br />55 <br />60 <br />Pipe Length <br />Point of Discharge ------11011:, <br />Elevation Difference I <br />-100'7 <br />F-18b <br />1.5 inch 2.0 inch 3.0 inch <br />Friaion locs per l 00 ft oC pipe <br />0.69 0.20 <br />0.96 0.28 <br />1.28 0.38 <br />1.63 0.48 <br />2.03 0.60 <br />2.47 0.73 0.11 <br />3.73 1.11 0.16 <br />5.23 1.55 0.23 <br />7.90 2.06 0.30 <br />11.07_ __ J.~. 0.39 <br />14.73 3.28 0.48 <br />3.99 0.58 <br />4.76 0.70 <br />5.60 0.82