Conductor Installation Services Ltd (CIS), an Acteon company that provides hammer services to install conductors and drive piles, announced that it successfully completed its first subsea piling services contract. CIS used its new remotely operated Subsea Piling System, which makes it possible to drive piles as large as 36-in. in diameter, in water depths to 300m. The piles were driven to permanently secure two subsea structures to the seabed and to initiate three rigid pipelines being installed by customer Technip on the Bøyla Development project offshore Norway.
In late March 2014, the team set out with all equipment to the Bøyla field. Working as weather permitted in a maximum water depth of 120m, CIS successfully drove the three 30-in. initiation anchor piles, four 30-in. manifold piles and four 24-in. pipeline end manifold (PLEM) piles. All piles were successfully driven into the seabed to their respective target depths, ranging from 10 to 23m. The subsea operation was successfully completed in April 2014, well within the requisite timeframe.
The subsea piling process is carried out by an experienced CIS engineer from a control unit and monitoring system located onboard a nearby vessel. A hydraulic hammer, connected via an electronic umbilical cable to the control system, is lowered into the water and placed directly over the subsea pile. Once it is accurately positioned, the pile will be driven into the seabed by the hammer until it reaches its target depth.
The scope of work was to install two different sizes of piles, which required re-dressing the pile-driving hammer to accommodate the second size of piles to be driven. Instead of transporting the hammer on the support vessel back to port to be re-dressed onshore, CIS and Technip worked together to formulate a more efficient solution to safely re-dress the hammer on the vessel in the field. By doing so, the time invested in this task was reduced, increasing vessel productivity by allowing it to remain in the field to carry out other work offshore. Throughout the operation, the Subsea Piling System performed as intended, confirming that the new technology reliably delivers substantial benefits.
“The success of this operation for Technip is particularly meaningful for CIS on many levels,” said Andy Penman, Group Managing Director of CIS. “In light of the years that we invested in developing the Subsea Piling System, it’s extremely satisfying that it really ‘hit the ground running,’ performing flawlessly during its very first commercial operation.”