Subsea turbines face some of the most severe weather conditions due to the offshore environment. Their reliability ultimately depends on the robustness and performance of the component parts that must withstand vibration, high bending, salt water, and high pressure.
With this in mind, this Ballgrab® connector provides a reliable structural connection between the nacelle and the turbine base. The connector significantly reduces installation times, and therefore vessel time, as each connection can be completed within minutes due to the connector being based on First Subsea's proven ball and taper mooring technology. The nacelle connector has no water depth limitation and it is ideal for resisting high bending moments to provide a secure connection. This means it is ideal for connecting large, high load structures in a subsea environment. The installation is diverless and ROVless meaning not only can the installation be completed quickly, it also means fewer people are required on deck during installation.
Wind Turbine Connector
The Ballgrab® wind turbine cable connector provides a ROVless and diverless cable connection for the installation of offshore wind turbines. Due to the quick connect and disconnect time and the fact that no diver or ROV intervention is needed during installation, this means that significant vessel time can be saved. Due to the lean design of the connector, greater operational flexibility, tighter installation tolerances and greater depths can be achieved due to the Ballgrab’s® unique integrated cable and connector design.
The wind turbine connector is a self-activating mechanism which allows rapid deployment. The male connector is guided into the receptacle on the wind turbine and, once engaged, cannot be released until the load has been removed. A simple disengage mechanism allows the tool to be released and recovered for re-use. Seals such as water barrier seals, can be incorporated into the connector to minimise any oxygenated water and swell entering the receptacle.
Based on First Subsea's LankoFirst, the rope connector uses the technology gained from LankoFirst to create a rope to interface connector. The rope connector offers a unique system enabling fibre rope to be securely fastened to a flanged interface, clevis or pad eye. Due to the compact design, it is easy to handle offshore and it also minimises splice length compared to traditional eye and thimble connections, enabling short tethers to be produced.
The connector can be coupled with a universal joint and bell mouth to further protect the rope in highly dynamic environments. Due to the connector's simplicity there are no water depth limitations.
As the rope connector is based on LankoFirst technology, the technology within the rope connector has been trialled in offshore Norway.
The trials in offshore Norway show that using LankoFirst technology significantly reduces the time it takes to assemble rope to rope and rope to interface. It also shows that it reduces the number of people needed to assemble the connector which means fewer people are required on deck during hazardous line make-up operations. See LankoFirst page
Fibre Rope Connections
In place of a large spliced soft eye, normally used with H-link and shackle connections, like LankoFirst, the rope connector uses a sub-connector Donut which is integrated into the rope termination during manufacture. This innovative and smaller donut splice is much easier to handle offshore.
The rope connector design relies on the rope being spliced into a forged steel, sub-connector during rope manufacture. These are subsequently secured within the connector during connector make-up offshore. This has clear practical benefits in terms of the ease and speed of mooring line deployment offshore.
Comprehensive Tool Testing
All of First Subsea's connectors are assembled and tested at First Subsea's head office in Lancaster. First Subsea's test facilities includes a test rig for proof load and Minimum Breaking Load (MBL) testing, which includes test facilities up to 2,600T to ensure we stay the class leading supplier for deep water projects. First Subsea also has a purpose-built Bend Stiffener Connector (BSC) test rig is specifically designed to demonstrate the operation and function of the complete pull-in system ahead of deployment offshore. The rig is capable of simulating a riser/umbilical weight of up to 100T and it can also evaluate the angle of connector approach with the maximum riser loads applied.