The drawworks on a drilling system consists of a large winch drum, brakes and a power source. It raises and lowers the drilling line as required, often to support the installation of piping as the borehole deepens.
[pdf] Deepwater Horizon was an ultra-deepwater, dynamically positioned, semi-submersible offshore drilling rig owned by Transocean and operated by the BP company. On 20 April 2010, while drilling in the Gulf of Mexico at the Macondo Prospect, a blowout caused an explosion on the rig that killed 11 crewmen and ignited a fireball visible from 40 miles (64 km) away. The fire was inextinguisha. DesignDeepwater Horizon was a fifth-generation, RBS-8D design (i.e. model type), deepwater, , column-stabilized, semi-submersible , designed to drill wells for oil explorati. .
Deepwater Horizon was built for R&B Falcon (which later became part of ) by in , South Korea. Construction started in December 1998, the was laid on 21 March 200.
[pdf] The Appomatox field was discovered in March 2010 by drilling the discovery well at Mississippi Canyon block 392. The well was drilled to a depth of 7,643m (25,077ft) and encountered approximately 162m.
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