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PRESSURE DISTRIBUTION SYSTEM 1. Select number of perforated laterals _ 2. Select perforation spacing = r? ft. 3. Since perforations should not be placed closer than 1 ft. to the edge of the rock layer (see p. E-14),subtract 2 ft. from the rock layer length. .37 -2 ft. 4. Determine the number of spaces between perforations. Divide the length above by perforation spacing and round E-17a down to nearest whole number. --TABLE OFPERFORATION DISCHARGES INCPV Head Perforation diameter(inches) Length perf. spacing =3.r ft. +S ft. spaces 207- 1 4 (3) (2) t.oa o.A 1.5 0.90 5. Number of perforations is equal to one plus the number of 2.ob 0.80 1.04 2.5 0.89 1.17 perforation spaces . 3.0 0.98 1.28 4.0 1.13 1.47 y5.0 1.26 1.65 spaces + 1 = /z perforations/lateral allse 1.0 foot of head for residential systems. bUx 2.0 feet of head for other establishments 6. Multiply perforations per lateral by number of laterals to get total number of perforations. E-17b J 12NrorM.Nw�rd�e=6 pre lff Wwau �10%Owsagv vwlr laterals x perfs/lateral- -34 perforations. ��a 1Z inch 1.5 inch 2.0 inch 2.5 14 18 28 7. Determine required flow rate by multiplying 3.0 13 17 26 3.3 12 16 25 number of perforations by flow per perforation 4.0 11 15 23 (see page E-17) 5.0 10 14 22 pals x a-/perf= zO gpm' E-15 -ma a rwrts,Tr 8. If laterals are connected to header pipe as shown on page E- 15,select minimum required lateral diameter from table on ..Y- page E-17;enter table with perforation spacing and number of perforations per later 1. Select minimum diameter for perforated lateral = 1 Ti inches. E-12 9. If perforated lateral system is attached to manifold pipe near the center, as on page E-12, perforated lateral length and number of perforations per lateral will be approximately one half of that in step 8. Using these values,select minim diameter for perforated lateral from page E-17 as--/'Tot, inches.