Definition(s)
Upper Kelly Cock
A valve immediately above the kelly that can be closed to confine pressures inside the drill string.
Source: API RP 7G, Recommended Practice for Drill Stem Design and Operating Limits, Upstream Segment, Sixteenth Edition, August 1998 (Addendum 2: September 2009). Global Standards
Upper Kelly Cock
Valve immediately above the kelly that can be closed to confine pressure inside the drill stem.
Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards