In oil drilling, a casing head is a simple metal welded or screwed onto the top of the (also known as drive-pipe) or the and forms part of the system for the well. The casing head in a conventional wellhead system is the lowest part of the wellhead assembly and is almost always connected to the surface casing string. It supports the remaining parts of the wellhead and completion equipment. The casing head performs the following functions:
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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).
[pdf] China's $1 billion oil drilling rig, the Haiyang Shiyou 981 – owned and operated by the China National Offshore Oil Corporation – in the South China Sea, Ocean Oil 981 – began its first drilling operations in 2012. [19][20] It led to protests and hence had to be shifted back. .
The impact of the has been increasing globally as the ranks seventh for and second in consumption in the world. China became the world's largest .
China's land-based oil resources are mostly concentrated in the country's north. Large oil fields include , , , , and Dagang.China's proven oil. .
Strategic Petroleum ReserveChina has one of the world's largest (GSPR), which is held for .
Early historyThe late banned mining because of the traditional cosmological beliefs which regarded the land as a sacred legacy. This. .
This shift to dependence on foreign oil has changed the exploration and acquisition policies of China. China's oil need overwhelmed its.
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