April 2009 Vol. 236 No. 4

Projects

GE Oil & Gas Completes Challenging Inspection Of Decades-Old Natural Gas Pipeline

GE Oil & Gas’ PII Pipeline Solutions group has helped National Grid USA complete a challenging inspection of a decades-old natural gas pipeline below New York City, showcasing the heightened efforts of operators to evaluate the condition of pipelines located in high-population areas.

National Grid hired GE to inspect a two-mile, 24-inch “Backbone” pipeline that runs beneath Brooklyn and under an East River tributary into the borough of Queens. After acquiring the assets of KeySpan Energy in 2007, the UK-based utility worked with multiple state and city government agencies to secure the needed permits.

“Enhancing the integrity of this important legacy pipeline, with the help of GE Oil & Gas, demonstrates National Grid’s corporate commitment to invest in our infrastructure security and stringent environmental protection programs,” said Mike Kern, manager of Asset Replacement Program, U.S. Operations.

The Brooklyn project posed a daunting logistical challenge, as National Grid wanted to avoid interrupting the flow of gas for extended periods of time despite the need for crucial excavation work to be performed at a busy intersection. Complicating matters further, the pipeline did not have any standard launch or receive traps to accommodate inline inspection (ILI) pigs.

To avoid the need for extensive excavation work, GE deployed its Smart Launch system, a patent-pending, hot-tap process to install a permanent, angled launch/receiver fitting in the existing pipeline. This fitting also will allow National Grid to conduct future inspections. Following the hot-tap process, GE deployed its SmartScan inline inspection tool, a flexible, multi-diameter intelligent pig that is able to navigate such previously unpiggable lines to successfully complete the inspection.