Utah State Exhumes PVC after Decades of Service

In recent years, researchers have exhumed PVC pipe to see if it would still meet the standards for which it was manufactured. These dig ups, which have taken place in Australia, the United Kingdom, Europe and the United States have been compiled into the PVC Longevity Report (2) and produced a set of data that supports PVC’s claims to strength, longevity and cost efficiency. 



From the other side of the globe, Stahmer (5) took into consideration the field performance of PVC pressure pipe and explored exhumed samples to see if they could still meet Australian and ASTM standards. PVC pipes were exhumed after 25 years of operation with samples differing in diameter and pressure class. Researchers subjected each sample to a deflection test of 60 percent or 40 percent of original I.D., an impact test using a weight falling 2 meters (size of weight differed on pressure class and diameter) and a test on tensile properties. 



Each sample that was tested exceeded the testing benchmarks they were put through, meeting both Australian and ASTM standards. Also noted from this research was that pipe samples had not suffered any loss of strength from years of operation and no degradation had taken place. 



In the United Kingdom and Europe, Alferink (1) dug up PVC pipe that had been in service between 35 and 37 years. He concluded that there was no change in the mechanical properties of the pipe due to aging. Also concluded from this research was that the pipe’s tensile strength did not decrease with pipe age and still met CEN stress regression requirements.



Hülsmann (3) performed hydrostatic tests on PVC pipe that had been in use for 23 years. From this research, he was able to conclude that under realistic operating conditions, the tested PVC pipes could easily operate for another 100 years. 

Finally in the United States, Moser and Kellogg (4) gathered 59 pipe samples from 16 different utilities and 10 manufacturers; each sample was subjected to both an acetone and impact test. All samples passed the acetone test and over 93 percent passed the impact test. Results from this dig up revealed that there was some early pipe failure, however, those instances could be attributed to improper installation. 



It’s clear that people from across the globe believe that PVC pipe is a material that starts and stays strong. With conservative estimates believing that properly installed PVC pipe should be in service for 100 years, it’s no wonder why PVC is considered the most sustainable piping solution. 



For more information on these dig up reports, feel free to check out the references below and the technical information provided by the PVC Pipe Association. Also, for more information on PVC piping products, contact us at Diamond Plastics. 



References

1. Alferink, F., Janson, L.E., Holloway, L., “Old PVC-U Water Pressure Pipes: Investigation into Design and Durability,” PVC 1996 Conference Proceedings, 42C382 Institute of Materials, Brighton, England, April 1996



2. Folkman, S, “PVC Pipe Longevity Report,” May 2014



3. Hülsmann, T., and Reinhard, E. N., “70 Years of Experience with PVC Pipes,” 13th World Pipe Symposium, Milan, Italy, April 2004. 



4. Moser, A. P. & Kellogg, K., “Evaluation of Polyvinyl Chloride (PVC) Pipe Performance,” AWWA Research Foundation, Project #708, Order #90644, February, 1994. 



5. Stahmer, M. W., and Whittle, A. J., “Long Term Performance of PVC Pressure Pipes in a Large Rural Water Supply Scheme,” Plastics Pipes XI Conference, Munich, Germany, Sept. 2001.