In This Issue

Reconsideration of Natural Gas Pipeline MAOP for Class Locations

Docket No. PHMSA-05-23447

On March 21, 2006, the Pipeline and Hazardous Materials Safety Administration (PHMSA) will hold a public meeting to discuss raising the Maximum Allowable Operating Pressure (MAOP) on certain natural gas transmission pipelines. PHMSA also invites papers on relevant technical subjects.

Over the past 20 years, there has been a drastic improvement in technology pertaining to materials, metallurgy, controls, operations, and maintenance of the pipeline network. Based on these and other advances, PHMSA believes that certain pipelines in certain locations could be safely and reliably operated above the operating pressure established in current Federal pipeline safety regulation.

There are three categories of pipelines that could realize an immediate benefit from such an increase in the MAOP:

– the proposed Alaska Natural Gas Transmission System;
– new natural gas pipelines that are being certificated by the Federal Energy Regulatory Commission; and
– pipelines constructed since 1980 with line pipe of known metallurgical and mechanical properties.

International pipeline regulations generally limit design stresses to 72% specified minimum yield strength (SMYS). Under highly selective conditions, some pipelines in the United States and Canada operate at hoop stresses up to 80% SMYS. Notwithstanding, the current United States Code of Federal Pipeline Safety Regulations (CFR) (49 CFR part 192) limits the stress to 72% SMYS for Class 1 locations, while Canada limits it to 80%. There are a lot of other countries considering operating at higher levels. Therefore, PHMSA believes it is appropriate to explore the reliability and integrity implications of operating pipelines at stress levels above 72% SMYS, but not to exceed 80% SMYS for Class 1 locations.

The benefits of an increase in MAOP for natural gas pipelines are tremendous, mainly because of the increase in capacity and fuel efficiency. For new pipelines operated at a higher MAOP, operators might realize an initial cost savings, primarily in materials. A capacity increase in existing pipelines will have an auxiliary benefit by avoiding the construction of new pipelines or costly modifications that have the potential to damage the environment. Historical problems associated with seam failures are non-existent with new materials. Most new pipelines have been configured to accept inline inspection tools to monitor the pipeline’s condition. Pipeline operators have improved their ability to manage internal corrosion. By allowing pipeline companies to safely increase the MAOP of existing pipelines that meet certain criteria, they could avoid new construction that can affect the environment.

Research by the Pipeline Research Council International concluded that pipeline operations can be safe and reliable at stress levels of up to 80% SMYS if the pipeline has well-established metallurgical properties and can be managed to protect it against known threats, such as corrosion and mechanical damage. Additionally, independent studies demonstrate the benefits of risk and reliability-based principles that strengthen safety.

This meeting provides the pipeline industry, Federal and State regulators, and interested members of the public an opportunity to share their knowledge and experience about the impact of increasing the MAOP to increase pipeline efficiency. Individuals that would like to make presentations should notify Mr. Joy Kadnar, Director, Engineering and Emergency Support at (202) 366-4595 or by Feb. 7, 2006, and submit papers at this meeting.

The meeting will be held at the Hyatt Regency Reston Hotel, 1800 Presidents Street, Reston, VA 20190. The telephone number for reservations at the Hyatt Regency Reston Hotel is (703) 709-1234. The hotel will post the particular meeting room the day of the meeting.