Directional drilling (or slant drilling) is the practice of drilling non-vertical . It can be broken down into four main groups: directional drilling, utility installation directional drilling, (horizontal directional drilling - HDD), and surface in seam (SIS), which horizontally intersects a vertical bore target to extract .
[pdf] A blowout preventer (BOP) (pronounced B-O-P) is a specialized or similar mechanical device, used to seal, control and monitor and gas wells to prevent , the uncontrolled release of crude oil or natural gas from a well. They are usually installed in stacks of other valves. The earliest blowout preventers; Regan Type K Annulars were used, beginnin.
[pdf] This article lists the main components of a onshore . rigs have similar elements, but are configured with a number of different drilling systems to suit drilling in the marine environment. The equipment associated with a rig is to some extent dependent on the type of rig but typically includes at least some of the items listed below.
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