Comparison of PVC and Ductile Iron Pipe

Material Properties of PVC and Ductile Iron

The material properties of PVC make PVC a better choice than Ductile Iron for many applications. The following table lists the properties for both PVC and Ductile Iron that are most important to the design of piping systems:

PropertySpecificationPVCDuctile Iron
Tensile Strength (PSI)ASTM D-6387,00060,000
Specific GravityASTM D-15051.407.1

Pressure Class Comparison

PVCDuctile Iron
Dimension RatioPressure RatingPressure ClassPressure Rating
DR 18235 PSI350350 PSI
DR 21200 PSI300300 PSI
DR 25165 PSI250250 PSI
DR 32.5125 PSI200200 PSI
DR 41100 PSI150150 PSI
DR 5180 PSI100100 PSI

Sample Pipe Comparisons

Horizontal Directional Drilling

Fusible PVC® will require a smaller bore hole diameter than other pipe systems. A smaller bore-hole diameter means that there will be less back reaming, less drilling mud, and less spoil disposal. The following comparisons illustrate these advantages.

HDD Comparison

Jack and Bore

The larger outside diameter of Ductile Iron pipe requires casing sizes to be larger in jack and bore applications. Fusible PVC® can utilize smaller casings, which ultimately lead to lower material and installation costs. In addition, Ductile Iron requires the use of casing spacers, which are not a requirement for Fusible PVC®.

Jack & Bore Comparison

Direct Bury / Open Cut

Fusible PVC® will require a more narrow trench width for direct bury than Ductile Iron Pipe, due to the larger outer diameter on the Ductile Iron Pipe. A smaller trench volume means that there will be less excavation, less backfilling and less spoil disposal. The drawing below illustrates these advantages.

Direct Bury / Open Cut Comparison