wiredInUSA December 2017

The trial, carried out in August, was conducted by inApril AS using Venator, its node-basedseabedacquisitionsystem,and supported by Makai Ocean Engineering Inc with its subsea cable deployment software, MakaiLay™ – Seismic module. inApril is a new Norwegian seismic equipment supplier. Venator focuses on high speed and “hands-off” installation and retrieval of seabed nodes. The test was conducted over a part of the Edvard Grieg field, operated by Lundin Petroleum. The MakaiLay seismic software provided feedback, based on proprietary cable model calculations, to ensure that the nodes were placed on the seabed accurately during the installation, and that the cable was not over-tensioned during the recovery. To accomplish this, the software uses inputs from all the navigation and cable control instruments on the vessel to calculate accurately, in real-time, the cable’s shape underwater, the touchdown position, and the slack or tension. The software can automatically adjust the vessel’s navigation and cable payout rate during the operation, or provide instructions to an operator, as was done during the inApril trial. When retrieving the nodes, MakaiLay provided the cable engine operator with values of tension at the touchdown point.

The trial was successfully completed in water depths of 110m, achieving safe deployment and retrieval speeds of 6 knots and 4 knots, respectively.

Transforming transmission Siemens has completed the testing stage of its first 1,100kV transformer, developed for an HVDC transmission link in China. The transformer was designed and developed by Siemens specifically for the link, which will be operated by the transmission grid operator State Grid Corporation of China (SGCC). In 2011, Siemens secured a contract, in partnership with undisclosed company, to deliver a total of seven±1,100kV transformers for the world’s largest HVDC transmission system.

S S Siemens has completed the testing stage of the 1,100kV transformer. Photograph courtesy of Siemens AG

wiredInUSA - December 2017

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