Rapid Encapsulation of Pipelines Avoiding Intensive Replacement
Cast iron, wrought iron, and bare steel natural gas distribution pipes—legacy pipes—make up 3% of the nearly 2 million miles of utility pipes in use, but account for a disproportionate number of gas leaks and pipe failures compared to more recently replaced infrastructure. REPAIR seeks to reduce natural gas leaks from these pipes by developing a suite of technologies to enable the automated construction of new pipe inside existing pipe. The new pipe must meet utilities’ and regulatory agencies’ requirements, have a minimum life of 50 years, and have sufficient material properties to operate throughout its service life without reliance on the exterior pipe. REPAIR will advance the state of gas distribution pipelines by incorporating smart functionality into structural coating materials and developing new integrity/inspection tools. It will also create three-dimensional (3D) maps that integrate natural gas pipelines and adjacent underground infrastructure geospatial information with integrity, leak, and coating deposition data. The cost target is $0.5-1 million per mile, including gas service disruption costs.
The Department of Transportation (DOT) and state regulatory agencies oversee gas distribution pipes. The suite of technologies developed under REPAIR will require coordination among multiple stakeholders and collaboration within research programs to achieve commercial success.
Legacy pipe malfunctions create operating risk and legal liability for utilities, negatively impact system owners’ financial performance, and are a cost burden to gas consumers. The current approach to repairing legacy pipes is to excavate and replace them, typically with high-density polyethylene pipe. The replacement cost ranges from $1-10 million per mile, depending on the pipe’s location (e.g., rural vs urban), degree of complexity of the excavation, such as congestion due to adjacent underground infrastructure, and costs for restoring roads. In addition, utilities incur costs whenever gas service is disrupted for repairs. REPAIR seeks to eliminate the highest cost components, excavation and restoration, by rehabilitating pipes without their removal—in essence, by automatically constructing a new pipe within the old.
REPAIR seeks to eliminate the highest pipe rehabilitation cost components, excavation and restoration, by repairing pipes without their removal.
REPAIR projects should improve the sustainability of domestic natural gas distribution by economically rehabilitating legacy pipes.
REPAIR will produce 3D maps and data management/visualization tools that integrate geospatial data for leak testing, integrity/inspection data, coating deposition data, and locations of pipes and adjacent underground infrastructure.
REPAIR program innovations will accelerate legacy pipeline replacement while reducing cost to utilities and gas customers.