Characterization and Fitness for Service of Corroded Cast Iron Pipe

Main Objective

This project has four primary objectives:

1. Provide a Fitness-For-Service (FFS) model and method for operators to characterize and grade graphitic corrosion defects on cast iron natural gas pipes. This will help operators make monitoring, repair, and replacement decisions, as well as prioritize accelerated replacement decisions related to cast iron mains and services.
2. Summarize and categorize the required input parameters to the FFS model related to cast iron material, graphitic corrosion geometry and characteristics, and operational environment.
3. Validate the FFS model by comparing its output to a statistically analyzed set of historical cast iron failure data.
4. Provide a physical testing program to fully validate the FFS model.

Public Abstract

Cast iron gas mains have been installed since the 1830's and they are still in service in many U.S. cities. About 32,400 miles of cast iron main is estimated to be in service in 2012, with about 50% of these pipes located within four states: New Jersey, New York, Massachusetts, and Pennsylvania. Consistent with the 49 CFR federal requirements, local distribution companies (LDC) have developed procedures for surveillance of their cast iron facilities to identify problems and take appropriate action concerning leak, breakage, and graphitization.

Recent incidents have prompted state regulators to evaluate and modify the utilities' procedures regarding the frequencies of the cast iron surveillance. Cast iron pipelines' vulnerability and their integrity are further highlighted in the PHMSA Safety Advisory Bulletin. This requires gas operators to implement a program, based on factors such as age, pipe diameter, operating pressure, soil corrosiveness, existing graphitic damage, leak history, and external loading, to identify and replace in a planned, timely manner cast iron piping systems.

This project seeks to provide a Fitness-For-Service (FFS) model and method for operators to characterize and grade graphitic corrosion defects on cast iron natural gas pipe. This will help make monitoring, repair, and replacement decisions, as well as prioritize their replacement program decisions leading to improved safety and supply stability.

Quarterly Status Reports

1st Quarter Report, Project Management - Public Page

DTPH56-15-T-000061stQuarterlyReport_PUBLIC.pdf (874,297 bytes) [View] [Download/Save...]

2nd Quarter Report, Project Management - Public Page

0_DTPH56-15-T-000062ndQuarterlyReport_PUBLIC.pdf (368,396 bytes) [View] [Download/Save...]

3rd Quarter Report, Project Management - Public Page

DTPH56-15-T-000063rdQuarterlyReport_PUBLIC.pdf (1,217,869 bytes) [View] [Download/Save...]

4th Quarter Report, Project Management - Public Page

DTPH56-15-T-000064thQuarterlyReport_PUBLIC.pdf (679,927 bytes) [View] [Download/Save...]