Disconnector eliminates release of hydraulic cylinder fluid into the sea

Hydraulic systems specialist, Enerpac, has announced a Remote Hose Disconnector designed to eliminate the release of hydraulic cylinder fluid into the sea during transition piece installation on offshore wind farms. The environmentally friendly development also allows full recovery of all connected equipment for reuse.

Hydraulic cylinders are a key tool in the installation of the transition piece on the monopile. Up to six fixation cylinders are used to hold the transition piece in position during grouting. They have to remain pressurized, via a hydraulic manifold, during the grouting and the subsequent curing time, which can take several days. At the end of this period, the cylinders and hoses need to be recovered.

Eliminates hydraulic fluid pollution

Until now, cutters have been used to cut the hose to depressurize the cylinders, releasing hydraulic fluid into the sea. Using the Enerpac Remote Hose Disconnector will allow the cylinders and hoses to be depressurised and recovered without hydraulic oil being released into the sea, as well as, avoiding the need to use a hose cutting tool and associated waste materials.

An Enerpac Remote Hose Disconnector is fitted directly onto each fixation cylinder. It comprises two, non-interchangeable, hose connections: one connector ensures oil flow to the fixation cylinder, the second one operates the disconnector itself.

After the grouting has cured, an Enerpac pump is connected via the same manifold with the second set of hoses. Operating the pump recovers all hydraulic oil and ensures full retraction of the plungers, the complete hose disconnector is then released from the fixation cylinder and ready to be re-used to install a new foundation. During the disconnection, no fluid is spilled into the sea. Potential residual oil in the cylinders is sealed from making contact with seawater, making this method fully sustainable.

‘Circular Economy’ Hose Disconnection

“The Enerpac Remote Hose Disconnector marks an environmental breakthrough in the installation of monopile and transition pieces,” said Patrick Frencken, Key Account Manager North West Europe, Enerpac. “Consistent with the ‘Circular Economy’, installation companies can extract maximum operational and environmental value from the remote hose disconnector, and fully recover it for reuse.”

The Enerpac Remote Hose Disconnector is tested and certified by Lloyds to 100m subsea and can be reused.