Technical Blog

Welcome to John’s Blog. Answers to frequently asked questions are periodically posted here. The objective is to share information about PVC pipe with readers as well as with utilities, design engineers and pipe installers. The blog provides the latest information on PVC pipe design, installation, and application for water and wastewater infrastructure projects.

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John Houle: Senior Technical Consultant, PVC Pipe Industry

John Houle holds a Master’s Degree in Civil Engineering from the University of Missouri and an MBA from the University of Oregon. He has more than 25 years of experience in the plastic pipe industry in applications engineering, market development, forensic analysis, technical writing, and standards development.

Today's Thinner-Walled Iron Pipe - More Susceptible to Corrosion

Posted By John Houle on Mar 8, 2017

The iron pipe industry likes to brag about pipe that has been in service for a long time – some for more than 100 years. However, it’s important to put this into proper context.

The fact is that most thicker iron pipes did not perform as designed for much of the time they were “in service.” They were often plagued with water main breaks, water loss, water quality issues as well as higher operating and maintenance costs due to corrosion well before the century mark.

Notwithstanding the above, the pipe they reference is a far cry from the pipe being installed today. 

There are two major differences:

  1. Material – today’s pipe is ductile iron and the old pipe is cast iron
  2. Wall thickness – today’s pipe is much thinner

The problem with thinner-walled pipe is that corrosion attacks thin-walled ductile iron at the same rate as thick-walled cast iron. The result is that, given the same environments, the expected life of ductile iron will be significantly less than for cast iron. 

For my tech brief on thinner and thinner walls equating to more and more corrosion, click here.