In DTH drilling, the percussion mechanism – commonly called the hammer – is located directly above the drill bit. The drill pipes transmit the necessary feed force and rotation to the hammer and the bit, along with the fluid (air, water or drilling mud) used to actuate the hammer and flush the cuttings. The drill pipes are added to the drill string successively behind the hammer as the hole gets deeper.
[pdf] An automated drill rig (ADR) is an automated full-sized walking land-based drill rig that drills long lateral sections in horizontal wells for the oil and gas industry. ADRs are agile rigs that can move from pad to pad to new well sites faster than other full-sized drilling rigs. Each rig costs about $25 million. ADR is used extensively in the . According to the "Oil Patch Daily News", "Each rig will generate 50,000 man-hours of work during the construction phase and up.
[pdf] In a drilling rig, the drill line is a multi-thread, twisted wire rope that is threaded or reeved through in typically 6 to 12 parts between the traveling block and crown block to facilitate the lowering and lifting of the drill string into and out of the wellbore.
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