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:
[pdf] The rotating head can be defined as a rotating, low-pressure sealing device used in drilling operations to seal around the drill stem above the top of the blowout preventer stack. Rotating drilling heads are used to safely divert air, gas, dust, or drilling mud away from the rig floor.
[pdf] China's land-based oil resources are mostly concentrated in the country's north. Large oil fields include , , , , and Dagang. China's proven oil reserves per capita are low. Province started producing in 1960, and by 1963 was producing nearly 2.3 million tons of oil. Production from Daqing declined, but in 1965, in Sh. In recent years, Chinese-manufactured oil rigs have earned a strong reputation in global markets due to their advanced technology, cost-efficiency, and comprehensive service support, especially for land drilling projects.
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