Well blowout preventer having improved feed screw apparatus

Claim 3

The apparatus according to claim 1 wherein said threaded feed screw is substantially cylindrical in shape except for having at least one flat surface along at least a portion of its length and said groove is formed in said at least one surface.

Claim 4

A well blowout preventer apparatus, comprising: a housing; resilient means within said housing for resiliently sealing a well pipe to the casing surrounding said well pipe; means to sealingly engage said resilient means with said well pipe; and means to lock said resilient means in place against said well pipe, said means including: an indexing tab secured to said housing; a threaded feed screw having an elongated groove along at least a portion of its peripheral longitudinal surface, said tab being located within said groove, whereby said feed screw is secured against rotation with respect to said housing; a threaded bushing threadedly engaging said threaded feed screw; and means to rotate said bushing to thereby advance said feed screw with respect to said housing, whereby said feed screw is advanced into engagement with said means to sealingly engage said resilient means with said well pipe.

Claim 5

A well blowout preventer apparatus, comprising: a housing; resilient means within said housing for resiliently sealing a well pipe to the casing surrounding said well pipe; means to sealingly engage said resilient means with said well pipe; and means to lock said resilient means in place against said well pipe, said means including: an indexing tab secured to said housing; a threaded feed screw having an elongated groove along at least a portion of its peripheral longitudinal surface, said tab being located within said groove, whereby said feed screw is secured against rotation with respect to said housing; a threaded bushing threadedly engaging said threaded feed screw; and means to rotate said bushing to thereby advance said feed screw with respect to said housing, whereby said feed screw is advanced into engagement with said means to sealingly engage said resilient means with said well pipe.

Claim 6

The apparatus according to claim 3 wherein said threaded feed screw is substantially cylindrical in shape except for having at least one flat surface along at least a portion of its length and said groove is formed in said at least one surface.

Claim 7

A well blowout preventer apparatus, comprising: a housing; resilient means within said housing for resiliently sealing a well pipe to the casing surrounding said well pipe; means to sealingly engage said resilient means with said well pipe; and means to close said resilient means in place against said well pipe, said closing means including: an indexing tab secured to said housing; a threaded feed screw having an elongated groove along at least a portion of its peripheral longitudinal surface, said tab being located within said groove, whereby said feed screw is secured against rotation with respect to said housing; a threaded bushing threadedly engaging said threaded feed screw; and means to rotate said bushing to thereby advance said feed screw with respect to said housing, whereby the advancement of said feed screw causes said resilient means to sealingly engage said well pipe.

Claim 8

A well blowout preventer apparatus, comprising: a housing; resilient means within said housing for resiliently sealing a well pipe to the casing surrounding said well pipe; means to sealingly engage said resilient means with said well pipe; and means to close said resilient means in place against said well pipe, said closing means including: an indexing tab secured to said housing; a threaded feed screw having an elongated groove along at least a portion of its peripheral longitudinal surface, said tab being located within said groove, whereby said feed screw is secured against rotation with respect to said housing; a threaded bushing threadedly engaging said threaded feed screw; and means to rotate said bushing to thereby advance said feed screw with respect to said housing, whereby the advancement of said feed screw causes said resilient means to sealingly engage said well pipe.

Claim 9

A hydraulic blowout preventer having auxiliary mechanical locking feature, said blowout preventer comprising: housing means adapted to be placed around a conduit string; head means slidable in said housing means and arranged to sealingly engage the conduit string; head actuating means movably located in said housing means in abutting relationship with said head means; hydraulic actuating means in said housing means on said head actuating means and arranged to respond bidirectionally to fluid pressures introduced into said housing means; and, feed screw means, including: elongated feed screw means in said housing means having an elongated groove along at least a portion of its peripheral longitudinal surface; indexing tab means secured inside said housing means and engaging in said elongated groove thereby securing said feed screw means against rotation in said housing means; threaded bushing means about said feed screw means and threadedly engaged therewith; and, means for rotating said bushing means to axially move said feed screw means with respect to said housing means.

Claim 10

A hydraulic blowout preventer having auxiliary mechanical locking feature, said blowout preventer comprising: housing means adapted to be placed around a conduit string; head means slidable in said housing means and arranged to sealingly engage the conduit string; head actuating means movably located in said housing means in abutting relationship with said head means; hydraulic actuating means in said housing means on said head actuating means and arranged to respond bidirectionally to fluid pressures introduced into said housing means; and, feed screw means, including: elongated feed screw means in said housing means having an elongated groove along at least a portion of its peripheral longitudinal surface; indexing tab means secured inside said housing means and engaging in said elongated groove thereby securing said feed screw means against rotation in said housing means; threaded bushing means about said feed screw means and threadedly engaged therewith; and, means for rotating said bushing means to axially move said feed screw means with respect to said housing means.

Claim 11

The blowout preventer of claim 6 wherein said housing means comprises two substantially identical, opposed housing assemblies, said head means comprises a generally semi-circular, slidable ram head in each of said housing assemblies, said head actuating means comprises a piston rod abutting each said ram head, said hydraulic actuating means comprises a hydraulically actuated piston on each said piston rod, and said feed screw means comprises an elongated, partially cylindrical, threaded feed screw rotationally held in each said housing assembly and arranged to abut each said piston rod.