Large Diameter Drilling (LDD) and Barge Master have combined their expertise to complete a World first: drilling operations from a diving support and construction vessel (DSCV) in water depths in excess of 270m. By integrating LDD’s reverse circulation LD2500 drill rig with Barge Master’s motion compensation platform (BM-T700) LDD have successfully completed the installation of seven anchor mooring piles for a Catenary Anchor Leg Mooring (CALM) Buoy – with the technique employed, whilst unique and bespoke, having the potential for industry wide application.
The Project (Limetree Bay Installation) was executed in the Caribbean Sea, circa. 2km off the coast of St. Croix, USVI, for Imodco Terminals, a subsidiary of SBM Offshore. The Project was exceptionally challenging; operational and environmental constraints limited the use of more conventional methods. The LDD devised solution mounted the LD2500 to a cantilever beam which was subsequently affixed to the Barge Master T700 motion compensation platform. Typically, reverse circulation drilling takes place off a jack-up barge (JUB) or from the pile top itself, however substantial water depths (ranging between 80-275m), challenging sea-bed conditions (sea-bed slopes up to 17 degrees) as well as the physical attributes of the anchor pile design made this impossible. An innovative and robust solution was required. LDD’s selected solution combined the proven technology of Barge Master’s motion compensated platform and LDD’s LD2500 drilling system to a achieve a successful Project outcome.
The equipment spread was mobilised on-board DSCV SBM Installer during Q1 2019 in Rotterdam, after which she sailed to St. Croix, USVI. The Project works, namely the installation of seven anchor piles, were successfully completed by LDD to the client’s satisfaction – this included not only the drilling element, utilizing the BM-T700 platform for necessary motion compensation, but also the design and engineering pertaining to installation, pile handling and grouting elements. Barge Master’s motion compensated platform ensured a steady and balanced platform was possible and allowed for a secure and balanced drilling operation, from a floating vessel, in highly challenging conditions.
Watch the video about the project here.
Photo: the SBM Installer equipped with the BM-T700 and LD2500 drill