The first JIP will make pipeline free span intervention less costly, the second JIP will result in faster and more consistent pipeline repair, and the third JIP will optimize the design of pipeline components faster.
Free Spans in Trenches JIP –Gaps between the seabed and pipeline, known as free spans, can lead to vibrations which may damage the pipeline.
“Lack of knowledge about the extent of vibrations in small gaps that typically occur on sandy seabeds means that the industry is conservative and is potentially over-dimensioning designs and conducting unnecessary interventions,” says Olav Fyrileiv, project manager, DNV GL–Oil & Gas. “The DNV GL JIP aims to address this problem by developing improved free span assessments that will lead to fewer interventions and reduced cost.”
The project comprises computational fluid dynamic analysis combined with a significant test program, and the outcome will be an extension of DNV GL’s Recommended Practice for Free Spanning Pipelines (DNV-RP-F105). DNV GL has already partnered with Dutch pipeline operator BBL Company VOF and is now inviting other pipeline operators to also join the project.
Pipeline Repair JIP –Maintenance and modification technology on offshore pipelines is developing to accommodate deeper and harsher environments and to reduce downtime. Technology and operational experience have been developed through several projects, such as remote pipeline operations using hyperbaric welding and Statoil’s successful Hot Tap operations in the North Sea.
“DNV GL is inviting the main players in the pipeline repair equipment sector to collaborate with us in reviewing recent developments in pipeline repair and maintenance,” says Dag Øyvind Askheim, project manager, DNV GL–Oil & Gas. “We plan to develop formalized criteria and procedures in an updated version of DNV GL’s Recommended Practice on Pipeline Subsea Repair (DNV-RP-F113). The aim is to reduce the time and cost spent on the design and execution of pipeline repairs.”
Design of Pipeline Components JIP –Today, internationally recognized standards and recommended practices cover the limit state design of subsea pipelines. However, such design codes only provide high-level guidance on how to consider pipeline components within a pipeline system.
Currently, there is not a consistent and unified approach to the design of pipeline components. With modern pipeline standards, the pipeline design is optimized and this gap becomes even more pronounced. The objective of this JIP will be to develop an approach, based on industry experience and best practice, to pipeline component design that is compatible with a modern pipeline limit state design code such as DNV-OS-F101.
“The aim is to help prevent project delays, increased costs, and, in some cases, compromised safety, which can happen when the interpretation of codes is stretched,” says Jonathan Wiggen, project manager, DNV GL–Oil & Gas. “We are inviting major players working with pipeline systems and components.”
Asle Venås, DNV GL’s global director for pipelines, said: “Offshore pipelines are the veins on an offshore field development and represent a large part of the total investment, and the value of the transported product can be enormous.”