DUCTILE IRON PIPE - ejprescott.com

1 An Ultimate Techical Guide to DUCTILE iron PIPE. PRESSURE CLASSES. A Publication of Standard A. Dimensions &. Pipe Weights of A-7 Pressure Class . DI Pipe PIPE BARREL PUSH-ON MECHANICAL JOINT. PUSH-ON AND LAYING LENGTH LAYING LENGTH. MECHANICAL JOINT 18 FT. 20 FT. 18 FT. 20 FT. DEFL. DEFL. ANGLE ANGLE. PRESS. WT. PER MAX. WT. PER MAX. WT. PER MAX. WT. PER MAX. SIZE THICK.* *. CLASS LGTH DEFL. LGTH DEFL. LGTH DEFL. LGTH DEFL. IN. PSI IN. IN. DEG. LBS. IN. LBS. IN. DEG. LBS. IN. LBS. IN. 4" 350 ** 5 205 19" N/A 8 -18' 210 21" N/A . 6" 350 ** 5 300 19" 330 21" 7 -7' 305 27" 340 30". 8" 350 ** 5 395 19" 440 21" 5 -21' 405 20" 446 22". 10" 350 5 510 19" 565 21" 5 -21' 520 20" 575 22". 12" 350 5 655 19" 725 21" 5 -21' 665 20" 735 22". 250 770 855 790 870. 14" 300 3 825 11" 910 12" 3 -35' 840 " 925 15". 350 850 940 865 955. 250 940 1040 960 1060. 16" 300 3 1000 11" 1105 12" 3 -35' 1020 " 1125 15". 350 1060 1170 1080 1190. 250 1090 1205 1115 1230. 18" 300 3 1185 11" 1310 12" 3 -0' 1210 11" 1335 12".

2 350 1250 1385 1275 1410. 250 1290 1425 1315 1450. 20" 300 3 1395 11" 1545 12" 3 -0' 1420 11" 1570 12". 350 1470 1625 1495 1650. 200 1550 1710 1575 1740. 250 1725 1905 1750 1935. 24" 3 11" 12" 2 -23' 9" 10". 300 1855 2050 1880 2075. 350 .043 1985 2195 2010 2220. * Thicknesses and tolerances shall be in accordance with AWWA/ANSI C151 and C111 respectively. ** Calculated thicknesses for these sizes and pressure ratings are less than those shown above. Presently these are the lowest nominal thicknesses available in these sizes. Including bell; calculated weight of pipe rounded off to nearest 5 lbs. A-7. Technical Data A. Pipe for Pressure A-9 Class DUCTILE iron Pipe Diameters, Circumferences and Areas for Pressure Class Table No. 1. PRESSURE NOMINAL OUTSIDE INSIDE CLASS SIZE DIAMETER DIAMETER* AREA AREA* CIRCUMFERENCE CIRCUMFERENCE. (psi) (inches) (inches) (inches) (sq. in.) (sq. in.) (inches) (inches). 350 3" 350 4" 350 6" 350 8" 350 10" 350 12" 250 14" 250 16" 250 18" 250 20" 200 24" 150 30" 150 36" 150 42" 150 48" 150 54" * Based on DUCTILE iron Pipe Pressure Classes nominal thickness for all sizes as specified in AWWA C151, and on standard cement lining minimum thickness specified in AWWA C104.

3 The value of Pi ( ) used in calculations = Weights for Pipeline Design Weight of Pressure Class DUCTILE iron Pipe and Contained Water Table No. 2. NOM. GALS. WEIGHT LBS. PER FOOT NOM. GALS. WEIGHT LBS. PER FOOT. PRESS. SIZE HELD PRESS. SIZE HELD. CLASS (inches) (per foot) PIPE WATER TOTAL CLASS (inches) (per foot) PIPE WATER TOTAL. 350 3" 250 18" 350 4" 250 20" 350 6" 200 24" 350 8" 150 30" 350 10" 150 36" 350 12" 150 42" 250 14" 150 48" 250 16" 150 54" These weights are based on minimum class DUCTILE iron Pipe with minimum thickness standard cement lining as specified in AWWA C104 and on weight of water of pounds per cubic foot. The inside diameters are as given in Table No. 1. Pounds of water per foot = X ( in inches)2. Gallons of water per foot = X ( in inches)2. DUCTILE iron /Gray iron Weights POUNDS PER CUBIC FOOT TO CHANGE TO MULTIPLY BY. DUCTILE iron GRAY iron Gray iron DUCTILE iron DUCTILE iron Gray iron A-9. A. DUCTILE iron Pipe A-11 Pipe Research Association In the 1991 revision of the ANSI/AWWA C 150 designs standard for DUCTILE iron pipe, Pressure Class des- ignations were incorporated.

4 This raised questions from some utilities and engineers that traditionally specified DUCTILE iron pipe based on a Thickness Class designation. Pressure Class designations refer to the pipe's ability to hold pressure, whereas Thickness Class refers only to wall thickness. And, as shown below, the same conservative design approach for determining DUCTILE iron pipe wall thickness continues without compromise. Example Design Criteria: Net Thickness: Nominal diameter: 6 inches Laying condition: Type 5. Depth of cover: 7 feet Working pressure: 100 psi. Surge allowance: 100 psi. Minimum Thickness: Net Thickness: Designing in accordance with AWWA CI50, using the following conservative design criteria, a net thickness of inches results: Factor of Safety: 2 for internal pressure, including surge 2 for ring bending +267% 2 for ring deflection Soil Density: 120 pcf Total Thickness: Minimum Manufacturing Thickness: In accordance with AWWA C150, a service allowance of is added to the pipe wall net thickness.

5 This results in a minimum thickness of which has 267% more wall thickness than required for design conditions. + 433% Total Thickness: To assure minimum thickness, a diameter-dependant allowance for the casting tol- Nominal Thickness: erance is added to the minimum thickness. In this example an allowance of is added to the minimum thickness. We now have a total thickness of which has 433% more wall thickness than required for design conditions. Nominal Thickness: The total thickness is often much less than the minimum pressure class nominal thickness. For our example the minimum pressure class nominal thickness of +733% exceeds the total thickness by an additional Thus, for this example, the minimum pressure class nominal thickness is 733% greater than required for design conditions. This conservative design approach is unmatched in the pressure pipe industry. Using this approach, Thickness Class 52 DUCTILE iron pipe would translate into a Pressure Class 1,000 with 933% more wall thickness than needed for the above design conditions.

6 Many utilities site corrosion concern as a reason for adding wall thickness. However, in our example, while the extra inches found between Thickness Class 52 and Pressure Class 350 provides a tremendous increase in pressure capac- ity, in a corrosive environment it would only extend the life of the pipe marginally. The most economical design calls for minimum Pressure Class selection based on loading requirements and polyethylene encasement (ANSI/AWWA Cl05/. ) to combat corrosion. A-11.