As the oil and gas industry continues its recovery and attention turns again to drilling and production in challenging and remote offshore locations, operators and drilling contractors are looking for technological and engineering innovations that give them that extra competitive edge.

One such focus is in the area of offshore anchoring, where there is a need to ensure stability, holding power and ongoing operations for offshore oil and gas assets in the most difficult of seabed conditions. This must take place while ensuring cost, drilling and production efficiencies.

Hard soils can cause significant operational and cost challenges. Areas where hard soils proliferate (among many others) include the Northwest Shelf of Australia, where calcarenite—a type of limestone composed predominantly of detrital sand-size and carbonate grains—is commonly found; the Arctic with its hard soil conditions, subsea permafrost, complex gravel and over-consolidated clays; and offshore the United Arab Emirates (UAE), which consists of mostly carbonite muds with very hard and complex soils, cemented materials and rocks.

In such hard soil environments, multiple anchors (piggyback arrangements that consist of two or more anchors) are required to generate the necessary anchoring force. In other cases, grout or driven piles are used as anchoring solutions, increasing the technical complexity and cost.

Anchor holding issues (excessive drag on anchor points) under such hard soil conditions can also increase drilling and production downtime with the anchors needing to be redeployed several times, again slowing down operations. It's with this understanding of operational pressures and seabed conditions that Vryhof Anchors, a trusted partner to many of the offshore industry’s leading companies, is introducing an innovative new drag embedded anchor at OTC this year—the STEVSHARK REX.

The STEVSHARK REX builds on Vryhof Anchor’s decades of anchoring experience. The new fluke and shank geometry enables easier, better and deeper soil penetration as well as added stability. Testing has shown an increase in holding power of between 22% and 45% (depending on different ground conditions) compared to alternative anchors.

As a result, the STEVSHARK REX enables the geographical, geotechnical and suitability boundaries of drag-embedded anchors to be expanded to some of the world’s most remote and challenging territories, opening up new resources in areas previously considered off-limits.

The STEVSHARK REX also provides a much more cost-effective anchoring solution. For drilling contractors and oil and gas and renewables operators, there is a minimizing of downtime, a cost-effective alternative to using grout or driven piles and their accompanying costs and time constraints, and an increase in site suitability options.

The lack of anchor drag also speeds up operations and optimizes drilling and production. Other benefits include greater flexibility in vessel and timing options and increased predictability in knowing that the STEVSHARK REX can effectively penetrate the hard seafloor.

A 7-ton prototype of the STEVSHARK REX was successfully tested in 2016 at two North Sea fields characterized by hard seabed conditions. A total of 15 tests took place in cooperation with a major oil and gas operator, where drilling rigs had previously used piggyback anchors.

Two 18-ton STEVSHARK REX anchors have also been shipped to Australia and the UAE. The anchors are going to be used by a dredger contractor and a drilling rig application and will allow Vryhof Anchors to collect more experience-based data on outcropping rocks and locations with limited sediment above the bedrock. The first results from the dredging application are also highly encouraging, with the STEVSHARK REX posting higher performance than previous anchoring alternatives.

Vryhof Anchors prides itself on listening to its customers and identifying future trends. In designing an anchor that provides holding power in the most extreme conditions, it has achieved just that—increasing efficiencies, protecting assets and reducing operational time and risk.

For further information on Vryhof Anchors, visit the Vryhof booth 1331.