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stabbing valve

1. n. [Well Workover and Intervention]
A valve that is connected to the work string in the event that the well starts to flow when running or retrieving the string. A stabbing valve generally is kept on the rig floor as a contingency against unexpected well flow. On snubbing operations, a stabbing valve, or safety valve, is kept in the workbasket to protect against tubing plug or backpressure valve failure.