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' University of Minnesota Pressure Distribution System Design - 10/25/04 <br /> AH boxed rectangtes�st 6e entered,fhe rest will be calculated. <br /> Or+srre <br /> Sewwoe <br /> 1. Seled number of perforated laterals: 0 TR�•TM�+* <br /> PRoo�eeuN ,. � <br /> 2. Select perforation spacing= �ft <br /> „�.�., <br /> 3. Since perforations should not be placed closer that 1 foot to ��«;""�v Y <br /> the edge of the rodc layer(see diagram),subtract 2 feet from i ry_��.k <br /> the rock layer len h t <br /> 50 -2 ft= 48 ft "`�="K;,=-s".�- <br /> ���Y� <br /> 4. Determine the number of spaces beriveen perforations. <br /> Divide the length(3)by perforation spacing(2)and round down to nearest whole number_ <br /> Pertoration spacing= 48 ft/ 3 ft= 16 <br /> 5. Seled perforation size 1/4 inch <br /> 6. Number of perforations is equal to or�plus the number of perForation spaces(4). <br /> `Check figu►e E-4 to asswe the number of perfr�rations per lateral gusranAses <br /> <10%dischaige variation. <br /> 16 spaces+1 = 17 perforations/lateral <br /> E�Maximum Number of 1/4 inch perforations E-5 Maximum Number of 3N6 inch perforations <br /> r lateral to uarantee<10%discha variation r lateral to uarantee<10°�dischar e variation <br /> Pertoration Perforation <br /> Spacing Pipe Diameter Spacing Pipe Diameter <br /> ft 1 inch 1.25 inch 1.5 inch 2.0 inch feet 1 inch 125 inch 1.5 inch 2.0 inch <br /> 2.5 8 14 18 28 2.5 12 19 25 39 <br /> 3.0 8 13 17 26 3 11 18 24 37 <br /> 3.3 7 12 16 25 3.3 10 17 23 36 <br /> 4.0 7 11 15 23 4 i0 16 21 33 <br /> 5.0 6 10 14 22 5 9 15 20 31 <br /> 7. A.Total number of perforations=perforations per lateral(5)times number of laterals(1). <br /> 17 perfs/lat x 3 laterals= 51 perforations <br /> B.Cakx�late the square footage per pertoration. <br /> Recommended value is Cr10 sqft/perf.Does not appty to at-grades. <br /> 1_ Rodc bed area=rock width(ft)x roc*length(ft) <br /> 10 ft x 50 ft= 500 ft <br /> 2. Square f�t per pe�foration=Rodc Bed Area/number of perfs(6) <br /> 500.0 ft/ 51 perfs = 9.8 fl 1 perf <br /> 8_ Determine required flovu rate by multiplying the total number <br /> of perforations(6A)by flow per perforations see figure E-6) <br /> 51 perfs x 0.74 gpm/peris= 37.7 gpm <br /> E�Perforetion Dischar e in GPM <br /> Head Perforations diameter <br /> feet inches <br /> 3l16 7/32 1!4 <br /> 1 0.42 0.56 0.74 <br /> 2° 0.59 0.80 1.04 <br /> 5 0.94 1.26 1.65 <br /> a Use 1.0 fod fa singl�tamiy homes. --------------------- <br /> b.Use 2A feei for else _. •". <br /> ._r <br /> � , <br /> ._ti�...,., � <br /> 9. Detertnine Minimum Pipe Size ^ �� - = I <br /> A. Manifold on End. If laterals are conneded to header pipe � _ <br /> as shown in Figure E-1,to se�ect minimum required lateral Ro�E-,:M����aE,.a«�.,�„ � <br /> diameter,enter figure E-4 or E-5 with pertoration spacing and <br /> --- --_ __ <br /> number of perforations per lateral.Select minimum diameter <br /> for perforated laterals= 2.0 inches <br /> B. Center Manifold. If perforated lateral system is attached to �E=M�.� - - --- <br /> N CenMa1MARIwn __ <br /> manifold pipe near the center,like Figure E-2,perforated lateral length(3) _- <br /> and number of perfora6ons per lateral(5)will be approximatey � _-- <br /> one half of that in step A. Using these values,seled <br /> minimum diameter for perforated lateral= 1.5 inches ' ``Z_ '� ' I <br /> I hereby ' that I have completed this work in accordance with all applicable ord'manoes,rules and laws. <br /> '� (signature) 810 (license#) 06/07/08 (date) <br />