• (#22) is a section of large diameter pipe fitted to the top of the that the attaches to via a side outlet, to allow the to flow back to the .• (BOPs) (#23 and #24) are devices installed at the wellhead to prevent fluids and gases from unintentionally escaping from the . #23 is the annular (often referred to as Hydril named after a manufacturer), and #24 is the pipe rams and blind rams.
[pdf] A derrick is a composed at minimum of one , as in a , which may be articulated over a load by adjusting its . Most derricks have at least two components, either a guyed mast or self-supporting , and a boom hinged at its base to provide articulation, as in a stiffleg derrick. The most basic type of derrick is controlled by three or four lines connected to the t.
[pdf] There are various types of derrick based on how the tower or mast is set up and the use of boom. An A-frame derrick is one in which the boom is hinged from a cross member between the bottom ends of two upright members spread apart at the lower ends and joined at the top; the boom point secured to the junction of the side members, and the side members are braced or guyed from this junction point.
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