Bullheading In Drilling Oil & Gas Wells Full Guide
Bullheading is a technique that may be used in certain circumstances during drilling operations to pump an influx back into the formation. In other words, it is a term to denote pumping into a closed-in well without returns. A major concern with this technique is that it may result in fracturing any exposed formation.

Bullheading is, however, a relatively common method of killing a well during workover operations when there is adequate reservoir permeability.
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