Laserfiche WebLink
• <br /> PRESSURE DISTRIBUTION SYSTEM Geotextile fabric <br /> ; e: ..• ;en'Pt'e. .. .vrt.r i-.-tor. :. .. .. ., ..'0'47 <br /> 1. Select number ofperforated laterals 12" <br /> Quarter inch perforations spaced 0 3' <br /> A <br /> 9"of rock <br /> 2. Select perforation spacing = 3. 0 ft <br /> Perf Sizing 3/16"-1/4" <br /> 3. Since perforations should not be placed closer than 1 foot to Perf Spacing 1.5'-5' <br /> the edge of the rock layer (see diagram),subtract 2 feet from <br /> the rock layer length. E-4: Maximum allowable number of 1/4-inch perforations <br /> �" per lateral to guarantee<10%discharge variation <br /> Rock layer length -2 ft - tat,/ ft <br /> perforation <br /> spacing <br /> 4. Determine the number of spaces between perforations. <br /> Divide the length (3) by perforation spacing (2) and round (feet) 1 inch 1.25 inch 1.5 inch 2.0 inch <br /> down to nearest whole number. <br /> 2.5 8 14 18 28 <br /> Perforation spacing= to3c• ft_ - ft= a. spaces 3.0 8 13 17 26 <br /> 5. Number of perforations is equal to one plus the number of 3.3 7 12 16 25 <br /> perforation spaces(4). Check figure E-4 to assure the number of 4'0 7 11 15 23 <br /> perforations per lateral guarantees <10% discharge variation. 5.0 6 10 14 22 <br /> '-). spaces + 1 = 2 ". perforations/lateral E-6: Perforation Discharge in gpm <br /> 6. A. Total number of perforations = perforations per lateral (5) perforation diameter <br /> times number of laterals (1) head Inches) <br /> (feet) 3/16 7/32 1/4 <br /> ' ,.-2, perfs/lat x ;? lat= La j perforations 1.00 0.42 0.56 0.74 <br /> B. Calculate the square footage per perforation. <br /> 2.0b 0.59 0.80 1.04 <br /> Should be 6-10 sqft/perf. Does not apply to at-grades. <br /> Rock bed area = rock width (ft) x rock length (ft) 5.0 0.94 1.26 1.65 <br /> Vie / A <br /> )o ft x <br /> � ft= i sqft ° Use 1.0 foot for single-family homes. <br /> Square foot per perforation = Rock bed area -number of perfs (6) b Use 2.0 feet for anything else. <br /> 0 soft_ o`7 perfs = a),'i° sqft/perf <br /> MANIFOLD LOCATED AT END OF PRESSURE DISTRIBUTION SYSTEM <br /> 7. Determine required flow rate by multiplying the total number of <br /> perforations (6A) by flow per perforation(see figure E-6) _ A <br /> 111: <br /> , P4P _ n.E <br /> "I perfs x , /perfs = ��'; gpm ��----- <br /> 8. If laterals are connected to header pipe as shown on upper 1 <br /> example, to select minimum required lateral diameter;enter d'R�AFN <br /> figure E-4 with perforation spacing (2) and number of perforations \-/``"`M <br /> per lateral (5) Select minimum diameter for <br /> ,�,,jj..,, <br /> LAYOUT OF PERFORATED PIPE LATERALS FOR <br /> perforated lateral = . inches. PRESSURE DISTRIBUTION IN MOUND <br /> PERFORATED PLASTIC PIPE <br /> 9. If perforated lateral system is attached to manifold pipe near <br /> �PERFORATIONS SPAM>s• �,AE <br /> ENO U�n":::E A [.FOry, "_ 6 a Fer'''AFIDN <br /> the center,lower diagram,perforated lateral length (3) and VIEW <br /> number of perforations per lateral (5)will be approximately one .ERFOPR;SITOPCSPO^EeD,TDM D, <br /> half of that in step 8. Using these values, select minimum b. <br /> diameter for perforated lateral = inches. _ �, ,, •-w.,,7113..1.3-= <br /> //i_� or IF�pPAIEC nil R <br /> C `ESM <br /> I hereby certify that I have, ompleted this work in accordance with applicable ordinances, rules and laws. <br /> 4- (signature) 3v, (license#) /1 " 12--'t2? (date) <br />