AC and DC Stray Current Mitigation and Corrosion Control for a New Urban Pipeline

摘要

This case history discusses an evaluation of stray direct current (DC) influencing a 20-mile (32 km) long high pressure natural gas pipeline in a congested urban area. The pipeline is in an area of heavy stray DC influence from a network of DC powered rail transit lines. It also parallels several high voltage overhead AC power lines. The paper presents various field evaluation techniques including those involving coupons. Part of the stray current mitigation strategy involves coordinated communication with the rail transit operator in an effort to control the stray current directly at the source, i.e. the transit system.