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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Drilling derricks and Rig Masts consist of a steel framework with a square or rectangular cross-section. Their purpose is to support the hoisting equipment and rack the tubulars while tripping pipe. The number of joints in a stand (single-double-triple) that the rig can pull is dependent on the height of the derrick. .
The Drawworks is one of the most important components of the drilling rig (types of drilling rigs). The unit supplies the hoisting power, the. .
The Crown Blockas a drilling rig component is a fixed set of pulleys (called sheaves) located at the top of the derrick or mast, where the drilling line is threaded. The companion blocks to these pulleys are the traveling blocks. By using two sets of blocks in this fashion,. .
The Traveling Blockis a set of sheaves (pulleys) that move up and down in the derrick. The drilling line is threaded (reeved) over the. .
Attached to the bottom of the traveling blocks, the hook is required to hang the swivel and rig kelly(for drilling) and the elevator bales (for tripping pipe and casing).
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As of June 2010, there were over 620 mobile offshore drilling rigs (jackups, semisubs, drillships, barges, etc.) available for service in the worldwide offshore rig fleet. .
Offshore drilling is a mechanical process where a is drilled below the seabed. It is typically carried out in order to explore for and subsequently extract that lies in rock formations beneath the. .
Offshore drilling is usually done from platforms generically known as mobile offshore drilling units (MODU), which can be of one of several. .
Offshore oil and gas production is more challenging than land-based installations due to the remote and harsher environment. Much of the innovation in the offshore petroleum. .
Offshore oil production involves environmental risks, most notably from oil tankers or pipelines transporting oil from the platform to onshore facilities, and from leaks and accidents on the platform (e.g. and .
Around 1891, the first submerged oil wells were drilled from platforms built on piles in the fresh waters of the in . The wells were developed by small local. .
Notable offshore fields include:• the • the (offshore , , , and )• (in the and , part of the Ventura Basin) .
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