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] Is capable of drilling depth of 4000 m (13,100 ft) with 4-1/2" DP and represents the largest self-propelled truck mounted drilling rig in the lineup. It comes equipped with two C-18 diesel engines to serve as its main power source.
[pdf] Rugged, long-lasting design makes these amazing drill rigs as dependable as they are powerful. Dual rotary drill rigs have two rotary drive mechanisms, an upper rotary head and a high torque lower drive unit.
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