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, � , Ptn_�SEL,ECTION PROCEDLmE
<br /> �A. Debermine,pump capacity:
<br /> Gravity DlstribuHon oro ��ow►rioN OF A PERFORATED LATERAL
<br /> 1. Minimum suggested is 600 gallons per hour(10 gpm)to stay ahead of �„��,w,
<br /> water use rate. . i t �i�---`-
<br /> 2. Maximum suggested for delivery to a drop box of a home system is 2,700 . . T��� ..,.,,r„_..,.`
<br /> *`:::::::...... ... .... ,�,, a c.e�..�a�sm.k 1«hi.-
<br /> gallons per hour(45 gpm)to prevent build-up of pressure in drop box. a-: ��,,s,�e�,,.. ��',,,�°�",,,,,«,,,,,.,�„„„�.,,,,�,
<br /> �-.. :... ,��M�a r. rodn�.r)
<br /> Pwlao�law OrnIN INrinnalry
<br /> Pressure Distribution • Na o w« ,eo
<br /> 3: a. Select number of perforated laterals 3 'ia�+N� � � w � ��•Ea•
<br /> b. Select perforadon spacing=�_ft. ��'�`' � ` 'P- �•'���� ,
<br /> :��<. ., ..
<br /> 1_�. , ,... wiav,i.�.'t000ae.�
<br /> c. Su tract 2 ft.from the rock la er len th. '' � c�s�+�« °i1""N'�°'•'°'
<br /> Y � x�:=:
<br /> ._ �.
<br /> -2 ft._�,�ft. �{:�,:,: . ,�.,::�:: ::;
<br /> o.i.�i s.n ys�wn..
<br /> eNu..a�oan�9,ne L.y.. -
<br /> ' d. Determine thc number�of spaces between perforations.
<br /> Length perf.sp�cing=�`�ft.� 3 ft._�_spaces ?ABLE OF PERApRA770N DISCHARCES W CPM
<br /> e. 13 spaces+1 =�c�perforaHons/lateral
<br /> ' f. MulHply perforallons per lateral by number of laterals to Head Pertoration diametv(lnches)
<br /> �t total nu ber of perforations. ,�� ��,
<br /> � x �__�perforations.
<br /> . �.a � osb oaa �
<br /> _ g• ��'X 6Tp'.�a-�$Pm� 2.ob 0.80 i.0
<br /> 2S 0.89 1.17
<br /> SELECTED PiJMP CAPACITY m 3.0 0.98 ts8
<br /> --�-�-gP �.o �.�a t.a�
<br /> S.0 1.26 1.65
<br /> B.Determine head requirements:
<br /> '�1. Elevation ditference between um and int of dischar e. sUse 1.0 foot of head for residenHel systems.
<br /> � p � $ bUse 2A teet of head for other establishmmts
<br /> % (� feet , .
<br /> 2. If pumping to a pressure distribution system,add five feet for pressure
<br /> required at manifold
<br /> � feet
<br /> 3. Friction loss � p�p��g�h �
<br /> a. Enter friction loss table with gpm and pipe diameter. � Point of D;scharge
<br /> Rcad friction loss in feet per 100 feet from table. "�
<br /> F.L._ :• -� � � ft./l00 ft of pipe Elevetion Diffcrence
<br /> b. Determine total pipe length from pump to discharge p„n,P �,�:
<br /> point. Add 25 percent to pipe length for fitting
<br /> loss,or use a fitting loss chart. Equivalent pipe F-18b
<br /> length-1.25 times pipe length= - 1.5 inch 2.0 inch 3.0 inch
<br /> % i.`� x 1.25= r�I�' feet g�,m Frictlon lou per 100It af pipe
<br /> c. Calculate total friction loss hy multiplying ' 10 0.59 0.20
<br /> friction loss in ft/100 ft by equivalent pipe length. 12 0.96 0.28
<br /> Total friction loss= � x � �I= +100= �>� feet 14 1.28 0.38 '
<br /> 4. Total head required is the sum oE elev�tion diffcrcnce, 16 1.63 0.48
<br /> s ial head r uirements,and total friction 1oss. 18 2.03 0.60
<br /> F'� e9 20 2.47 0.73 0.11
<br /> ' 25 3.73 l.11 d.16 .
<br /> ��' + �' + �-�% 30 5.23 1.55 0.23
<br /> (1) (2) (3c) 35 7.90 2.06 0.30
<br /> 40 11.07 2.64 0.39
<br /> . 45 14.73 3.28 0.48
<br /> T01'AL HEAD I�, fect 50 • 3.99 0.58
<br /> SS 4.76 0.70
<br /> 60 5.60 0.82 '
<br /> '�C. Pump selection
<br /> 1. A pump must be selected to deliver at least 3 �,_gpm (Step�A)
<br /> with at least 1�7 feet of Eotal head (Step B).
<br />
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