Patent ID: 6896239

Claim:
An apparatus for locking a valve having a valve member movable between an open position and a closed position, the apparatus comprising: an actuator assembly having a reciprocal piston operatively coupled to move the valve member between the open position and the closed position, the actuator assembly being connected to a valve housing; a locking base fixed against movement relative to the valve housing, a through-bore extending from a lower portion to an upper portion of the locking base, a first thread provided on the upper portion, and a first locking bore extending transversely through the locking base and across the through-bore; and a locking shaft reciprocally extending through the through-bore of the locking base and including a lower end selectively abutting against the piston, an upper end having a second thread that is selectively engagable with the first thread of the locking base when the valve member is in a predetermined position, and a second locking bore extending transversely through the locking shaft intermediate the upper and lower ends and alignable with the first locking bore once the locking shaft is threadably engaged with the locking base a predetermined amount.