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] • : The said it was monitoring events in Vietnam closely, and urged restraint from all parties. Secretary of State , who is also a former , said the United States is "deeply concerned" that China has placed an oil rig in an area of the South China Sea also claimed by Vietnam, adding that the move was "provocative" and "aggressive".
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