When laying and retrieving submarine cables on the seabed, or performing a cable pull from a vessel to an offshore wind platform, it is often necessary to hold a cable end onboard for up to seven days.
Cables must be anchored firmly onboard to keep them in place, and this anchoring is normally done by means of a cable stopper.
The cable left hanging in the ocean can be exposed to forces so strong there is a distinct possibility of becoming overtensioned. Meanwhile, the vessel’s crew works to keep station by the use of thrusters. If overwhelmed by winds, strong currents and waves, the ship can be driven out of position. The cable left hanging may end up acting as an anchor chain, subject to additional forces and tension.
In these situations, when the wrong cable hardware is used, or is installed incorrectly, the grip of cable tensioners can slip. The heavy cable starts moving unfastened, which is extremely dangerous for the crew, equipment and the vessel.
While the oil, gas and seismic industries have had plenty of experience with these issues, the growing offshore renewable energy companies are looking to manufacturers like PMI Industries for proven experience and products to guide the way.
Engineers who have made the leap from offshore oil to offshore renewable energy have worked with PMI’s products, such as our CABLE-GRIP™ and STOPPER-GRIP™ Terminations, and have found them preferable to typical braided cable grips or cable socks. These terminations are quick and easy to install, robust, and recommended by many cable deck crews.
Our unique cable grips are fully capable of holding cables to the rated breaking strength. Tensile load is transferred gradually from cable to termination with no stress or damage to the cable. And unlike braided stoppers, the helical termination wire design permits installation anywhere along the length of the subsea cable, since it does not require access to the cable end.