State-of-the-art hydraulics for floating megastructure

21 March, 2017

This was all housed within a fabricated frame complete with ROV grab handles welded directly onto the cylinders; all designed and manufactured as per ISO 13628-8.

The hydraulic cylinders and the tensioning system that they are used for are installed months in advance of the FLNG being in position. Once the FLNG is in position and the flowlines are in tension, the four cylinders must be able to keep the holdback chains in place; withstanding the force of the pre-tension for up to 24 hours until the holdback chains can be locked into place by the ROV.

It has been a challenge building each aspect of building these bespoke hydraulics, with all specifications being extreme. Even the paint work went far beyond standard worldwide paint specifications (Norsok M 501). This was outsourced to a specialist company, to ensure absolute accuracy to the corporations very specific measurements.

Apex Hydraulics has welcomed regular inspections from the corporation’s third-party inspection agency, which was required to sign-off on multiple aspects of the work. The cylinders had full third-party NDT inspections carried out before assembly and also after pressure and functional pull testing, all as detailed in the Inspection and Testing Plan (ITP). In addition, there has been lots of very rigorous in-house testing.

Strength and precision

The process has reportedly resulted in an exceptionally strong, extremely precise hydraulic system that can be worked by an ROV at a depth of 240m below sea.

With over 30 years’ experience within the hydraulics industry, Apex Hydraulics has commitment to innovation in the design, manufacture and repair of hydraulic cylinders for the offshore / marine sector.

www.apexhydraulics.co.uk