Mechanical Back Off Drill Pipe Operation Procedures
Drill pipe or Drill collars can be unscrewed downhole by exploding a charge known as a string-shot (prima-cord folded up inside a piece of tubular plastic) inside a selected tool joint connection, just above the stuck point ( check also stuck pipe guide), this operation can be described as mechanical drilling pipe back off. A connection should be selected which has been broken during the round trip (check also tripping pipe) prior to the pipe becoming stuck.
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