First Permanent Mooring Work for InterMoor in China
This project was also the company’s first for Chinese installation contractor China Offshore Oil Engineering Co. Ltd. The Nanhai Sheng Kai floating, storage and offloading unit (FSOU) has been in service since 1992, surpassing its 12-year original estimated design life. Consequently, its subsea mooring system had begun to deteriorate and corrode. To facilitate continuing production from Lufeng field and the expansion of the LF 13-2 oilfield, the fields’ operator, China National Offshore Oil Corporation Ltd (CNOOC), is extending the service life of the FSOU by another 15 years by upgrading and relocating its mooring system to LF 13-2 oilfield.
During the five-month contract, InterMoor’s work included project management, engineering, procurement and installation for a new buoy turret mooring system for the upgraded Nanhai Sheng Kai FSOU in LF 13-2 field. Additionally, InterMoor spearheaded the installation of a new eight-inch flexible flowline and riser between the buoy turret mooring system and the LF 13-2 wellhead platform. The scope of work also included temporary replacement of the buoy turret mooring system in LF 13-1 field to accept the interim Nanhai Kai Tuo FSOU.
InterMoor was assisted on the project by three sister Acteon companies: Offshore Installation Services (OIS) provided project management support and offshore personnel; 2H Offshore provided riser installation engineering; and Aquatic supplied additional offshore personnel and equipment for deploying the flexible riser.
Martin Kobiela, operations director for InterMoor Pte Ltd, said, “Owing to the diverse nature of the offshore work scope, the main challenge was interfacing with the main installation vessel, the Maersk Attender, to accommodate the project requirements.” InterMoor’s expertise in back-of-the-boat solutions played a key part in executing the project efficiently and successfully. The company also designed custom devices to handle the jacketed spiral strand wires. With no large storage reels on the anchor-handling tug supply vessel, the jacketed spiral strand wires were spooled on the main winches using custom winch adapters.
InterMoor and OIS developed procedures so that operations could be performed simultaneously while working with divers, remotely operated vehicles (ROV) and the anchor-handling vessel in close proximity to the buoy turret mooring system. “We were selected for this project because of our competitive expertise and ability to provide all resources and services within the tight timeframe. All the work was carried out safely, efficiently and ahead of schedule,” Kobiela said. ”We are pleased to have had the opportunity to work closely with China Offshore Oil Engineering for the first time.”