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University of Minnesota Pump Selection Procedure - 10/25104 <br /> All boxed rectangles must be entered,the rest will be calculated. <br /> ONse-re 111.1i <br /> SEWAGE Determine pump capacity:dY• THEATMENT <br /> A. Gravity Distribution P"R"AM <br /> 1.Minimum required discharge is 10 gpm <br /> 2.Maximum suggested discharge is 45 gpm <br /> For other establishments at least 10%greater than the water <br /> supply rate,but no faster than the rate at which effluent will flow <br /> out of the distribution device. <br /> B. Pressure Distribution-see pressure design worksheet soil treatrnent system <br /> &print o discharge <br /> Selected Pump Capacity: 29 gpm total pipe <br /> length <br /> muff"' 2A.elevation <br /> inlet difference <br /> 2. Determine Total Dynamic Head(TDH) pipe <br /> A. Elevation difference between pump and point of discharge. <br /> 9 feet <br /> B. Special head requirement?(See Figure-Special Head Requirements) <br /> 5 feet Special Head Requirements <br /> Gravity Distribution Oft <br /> C. Friction loss in supply pipe Pressure Distribution 5ft <br /> 1. Select pipe diameter 2 in <br /> 2. Enter Figure E-9 with gpm(1A or B)and pipe diameter(C1) <br /> Read friction loss in feet •-r 100 feet from Figure E-9 E-9 Friction Loss in Plastic Pipe <br /> Friction loss= 1.55 ft/100 ft of pipe per 100 ft <br /> nominal <br /> 3.Determine total pipe length from pump discharge to soil system discharge point. Flow Rate pipe diameter <br /> Estimate by adding 25 percent to pipe length for friction loss in fittings. (gpm) 1.5" 2.0" 3" <br /> Pi•- len a th times 1.25=equivalent pipe length 20 2.47 0.73 0.11 <br /> 40 ft x 1.25= 50 feet 25 3.73 1.11 0.16 <br /> 30 5.23 1.55 0.23 <br /> 4.Calculate total friction loss by multiplying friction loss(C2) 35 6.96 2.06 0.3 <br /> by the equivalent pipe length(C3)and divide by 100. 40 8.91 2.64 0.39 <br /> Friction Loss= 1.55 ft/100ft X 50 ft / 100= 0.8 feet 45 11.07 3.28 0.48 <br /> 50 13.46 3.99 0.58 <br /> D. Total head requirement is the sum of elevation difference(A),special 55 4.76 0.7 <br /> head requirements(B),and total friction loss(C4). 60 5.6 0.82 <br /> 9 ft + 5 ft + 1.0 ft 65 6.48 0.95 <br /> 70 7.44 1.09 <br /> Total Head: 15.0 feet <br /> 3. Pump Selection <br /> 1.A pump must be selected to deliver-at least 29 gpm(1A or B) <br /> with at least 15.0 feet of total head(2D). <br /> I hereby certify that I have completed this work in accordance with all applicable ordinances,rules and laws. <br /> (signature) 810 (license#) 1/07/08 (Date) <br /> Page 1 of 1 <br />