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] This block is a set of sheaves (pulleys) that move up and down in the derrick. The drilling line is threaded (reeved) over the sheaves on the crown and through the sheaves in the traveling block. This provide.
[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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