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Successful Tests Stevshark Rex


18mT Stevshark Rex after biting calcareniteVryhof has successfully completed extensive field tests with the revolutionary Stevshark Rex anchor in Australian waters, proving its suitability for hard soils and carbonate rocks. This completely new anchor, with its radically new fluke and shank geometries has already been designated by insiders as the ‘game changer’ in the mooring industry.

In 2016 a total of fifteen tests were successfully carried out at three locations in the North Sea famed for their anchoring problems with stiff clays. In early 2017 the new anchor was used in the United Arab Emirates by a rock cutter suction dredger on cemented soils. The results received from this site were also very positive. For the most recent test, Vryhof selected test sites offshore Australia in close collaboration with Woodside Energy.

“We were very interested in getting the test results of the anchor in remote and challenging territories such as the Angel Field in the North West Shelf of Australia with complex cemented soils of carbonite origin or calcarenite to calcilutite to limestone rocks,” explains Amy Rathmel, Geotechnical Engineer with Woodside Energy. “These geological settings can be quite brutal and very hard, so difficult for an anchor to embed.”

Within a period of several days, Deep Sea Mooring Australia coordinated and executed the test. The 18t anchor with 7.2t ballast was tested in one hundred meters of water at four different locations, each with their own ‘extreme’ soil characteristics. For the execution of the tests, Farstad’s Far Scorpion, having a bollard pull of 251t, was deployed.

The first test took place in a carbonate silty sand seabed, up to 4m thick and overlaying calcarenite rock. The second test was performed in a thinner sediment (1–2m), also with rocks beneath. The soil for the third test consisted of calcarenite rock with rough/irregular topography, while the last test was in calcarenite rock with a smooth bedrock surface. All of the tests were successful. The holding power of the Stevshark Rex exceeded all expectations. The open geometry and the protruding fluke tips on the anchor effectively penetrated even the hard rock field at the final test site as predicted.

Leopoldo Bello, Managing Director of Vryhof Anchors says: “We are very pleased with the results of these tests offshore Australia, of course, proving that the anachor is more efficient, more predictable and stronger, and delivers holding power in extreme conditions unmatched by any other anchor.”

Video field Australian field tests