Across the oil and gas industry, life extension of assets and infrastructure is an increasingly important issue for operators as they look to balance the integrity, safety and productivity of the asset. To reflect the changing needs of the industry, DNV GL has worked together with its industry partners to update two recommended practices (RP). The first for corroded pipelines (DNV-RP F101) and the second for integrity management of submarine pipeline systems (DNV-RP-F116).

The updates have been developed through the completion of joint industry projects (JIPs). The revisions aim to further support the decision-making processes related to maintaining the integrity of pipeline systems in the following areas: extension of in-service operation; costly repairs and replacements; long-term planning of activities based on balanced evaluations of both technical and non-technical issues; and continuous improvement of integrity management systems.

Felix Saint-Victor, principal engineer - pipelines and materials, DNV GL Oil & Gas, said: "By its very nature, the pipeline sector is constantly evolving to meet regulatory requirements, address technology advances and react to an often volatile economic market. Likewise, recommended practices must keep ahead with these changes.

"The latest revisions to two RPs for the pipeline sector will help ensure that best practice is adhered to and that decision-makers have the most appropriate guidelines at their fingertips."

First issued in 1999, the latest update to DNV-RP F101 includes a new assessment methodology on how to estimate the pressure resistance of a pipeline containing long axial grooving (the methodology is also applicable for pipelines with other patterns of internal corrosion), and assessment of internal corrosion development with time.

Updates have also been made to achieve better compliance with the newest edition of the offshore standard DNV-OS-F101 rev. 2013-10, e.g. with regard to pressure definitions and terminology, characteristic material properties, partial safety factors and fractile values, and supplementary material requirements.

Integrity management is climbing further up the agenda as the industry looks to get the most from life extension of ageing pipelines. Corrosion in particular poses a major threat to these pipelines.