Patent ID: 7300033

Claim:
A subsea blowout preventer operator locking system comprising: a closure member; a first piston rod comprising a first end coupled to the closure member; a first operator housing comprising a first end coupled to a bonnet and a second end coupled to a head, wherein the first piston rod extends through the bonnet, wherein a second end of the first piston rod is at least partially disposed within the operator housing; a first piston at least partially disposed within the first operator housing, wherein the first piston comprises a body and a flange, wherein the second end of the first piston rod is coupled to the body of the first piston; a first sleeve slidingly disposed within a cavity disposed within the first piston, wherein the first sleeve is rotationally fixed relative to the first piston; a first lock rod rotatably coupled to the head and threadedly engaged with the first sleeve, wherein rotation of the first lock rod axially translates the first sleeve relative to the first piston; wherein one end of the first lock rod projects through the head and is operably engageable subsea from outside the first operator housing; and wherein the first piston is lockable in an extended position by rotation of the first lock rod to extend the first sleeve, the first piston being held in position by contact of an end of the first sleeve with the cavity of the first piston.