Severe Graphitic Corrosion
Severe Graphitic Corrosion in Cast Iron Drain Lines of a Health Care Facility
Vertical and horizontal waste water drain line located in a health care facility. Pipes were located in finished walls and the crawl space.
Cast iron drain lines should conform to ASTM A888, but the analyzed pipe did not comply with these specifications.
Approximately 23 years.
Mode of Failure
Severe graphitic corrosion and cracking due to the use of a cast iron material which did not meet specifications.
The drain line system contained multiple longitudinal and transverse cracks in the cast iron piping. Severe graphitic corrosion had also reduced the wall thickness of the piping in some locations to 1/16-inch or less, creating holes and leak sites, which in some locations, appeared as tubercle leak sites.