The Bureau of Safety and Environmental Enforcement (BSEE) responded to an equipment failure onboard Transocean's Deepwater Nautilus semisubmersible drilling rig in the US Gulf of Mexico, the agency reported on 10 June 2014.
Operator Shell Offshore Inc. reported to BSEE on 9 June that the rig’s traveling block fell during well operations. The traveling block is a large piece of equipment that supports the top drive. The Deepwater Nautilus' top drive is a Varco TDS-8S (AC) rated for 750 ST with parking assembly, according to Transocean's fact sheet on the semisub.
"Shell is monitoring the well," BSEE said. "There are no reports of injuries to personnel. There is no reported pollution. The project is limited to drilling; no production was affected by the incident."
BSEE said it will continue to investigate the incident, and plans to send engineers and inspectors to the rig as soon as weather permits.
According to BSEE's deepwater activity sheet, dated 9 June, the Deepwater Nautilus had been drilling at the Glider field, approximately 100mi south of Fourchon, Louisiana, in Green Canyon Block 248. The well sits at 3,233ft water depth. The Glider field was discovered in 1996, and is currently in phase two development.
The Deepwater Nautilus is a fifth generation semisubmersible, capable of operating in water depths up to 8000ft. It was built in 2000 by Hyundai Heavy Industries in Ulsan, South Korea. It utilizes an eight-point mooring system, and has a maximum drill depth of 30,000ft.
Image: Transocean/Deepwater Nautilus