Electric generators powered by large diesel engines (the prime movers) generate electricity that move the heavy rig equipment such as the rotary table (or top drive), mud pumps and drawworks. Electric drill rigs are more expensive than mechanical rigs, but offer some nice advantages in return.
[pdf] The drawworks reels in and reels out the drilling line. The drilling line is connected to the traveling block and hook which connect to the drill string. The drill string runs over the crown block and setup like a block and tackle pulley system.
[pdf] There are two separate but closely related parts of preparing for a drilling project—planning the well and designing the well. “Planning” means to list, define, schedule, and budget for all the multitud.
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