Abstract: A single or multi-bowl wellhead may be positioned in a diverter housing over the wellbore. Protrusions on the wellhead may be installed after the diverter housing is removed. The wellhead accommodates the direct connection of hydraulic lines to a hanger seated therein. An overshot running tool protects the wellhead during placement and certain operations.

Abstract: A single or multi-bowl wellhead may be positioned in a diverter housing over the wellbore. Protrusions on the wellhead may be installed after the diverter housing is removed. The wellhead accommodates the direct connection of hydraulic lines to a hanger seated therein. An overshot running tool protects the wellhead during placement and certain operations.

Abstract: The present invention is a wellhead system for use in completing at least two well bores from within a single conductor housing. The wellhead system comprises at least one wellhead housing which is supported on the conductor housing and which comprises a top portion that is adapted to be connected to a lower portion of a wellhead component, a casing hanger which is supported within the wellhead housing and from which a casing string is suspended, and a connector for securing the wellhead component to the wellhead housing. In accordance with the present invention, the connector is selected from the group consisting of a latch ring and a segmented clamp assembly.

Abstract: A mechanically energized annular packoff seal cartridge for metal-to-metal sealing with substantially concentrically arranged tubular members, such as the tubular wellhead housing and well casing of an oil and gas well. A tubular pressure responsive energizing mandrel having downwardly converging frusto-conical seal actuating surfaces is of a dimension for entry into the annulus between the wellhead seal bore and the rough outer surface of the well casing. Elastomer seals are carried by the energizing mandrel and establish sealing of the energizing mandrel with the wellhead housing and well casing A pair of soft metal seal rings are carried by the seal cartridge and are forced radially into metal-to-metal sealing with the wellhead housing and the rough outer surface of the well casing respectively by the double tapered seal actuating surfaces responsive to pressure induced downward force on the energizing mandrel.

Abstract: The present invention is a wellhead system for use in completing at least two well bores from within a single conductor housing. The wellhead system comprises at least one wellhead housing which is supported on the conductor housing and which comprises a top portion that is adapted to be connected to a lower portion of a wellhead component, a casing hanger which is supported within the wellhead housing and from which a casing string is suspended, and a connector for securing the wellhead component to the wellhead housing. In accordance with the present invention, the connector is selected from the group consisting of a latch ring and a segmented clamp assembly.

Abstract: A method and apparatus for installing a metal annular seal (54) between the outer rough surface of a casing member (11) which has had a portion thereof cutaway with a remaining portion projecting upwardly from the upper end of a casing head (12). A slip installation tool (18) mounted on the upper end of the casing head (12) carries a slip assembly which includes segmented slips (42), a bushing (22), and a cam member (42). The slip installation tool (18) secures the slips (40) about the outer rough surface of the casing (11) as shown in FIGS. 7 and 8 with bushing (22) acting as a supporting base or foundation to oppose the forces from the camming action because of support from lock down screws (24). After mounting of the slip assembly about the casing (11), the installation tool (18) is removed, and the metal seal (54), formed of a relatively soft metal material, is mounted over the extending end of the casing (11). Positioning of the tubing head (50) on the casing head (12) as shown in FIGS.

Abstract: According to the present invention, there is provided a device for guiding a tool on a string within a blow out prevention ("BOP") stack. In one embodiment, the device includes a top collar connected to a bottom collar by a shroud having a plurality of flexible members which bow outwardly from the collars, wherein the shroud covers a portion of the tool. An energy absorbing bumper is provided above the top collar to absorb structural impact caused by a blow out or other inadvertant pressure in a downhole application.

Abstract: A retrieval tool for retrieving a back pressure valve and tree test plug (generally, a check valve) has a spear formed as a solid ring at the bottom with free fingers extending upward. The fingers are resilient and have protrusions adapted to engage a retrieval groove in the check valve. A wedge ring is provided on the tool body to positively lock the fingers in radially outward engagement with the retrieval groove. The wedge ring is fixed to the body by a shear pin so that upon a predetermined axial force the pin shears and releases the wedge ring allowing withdrawal of the tool assembly, if the check valve is stuck in a tubing hanger or coupling.

Abstract: A subsea wellhead tieback connector operatively used to connect to a marine riser pipe or a well conductor in a manner that that will not unthread or unloosen the joints of the riser pipe being unlocked. The tieback connector operates with a novel internal latching mechanism having a hydraulic piston, an inner body that stretches and deflects in a unique manner resulting in compression spring forces at two locations, an expanding lock ring, a threaded adjustment ring, and a reaction ring. During operation the tieback connector creates an enhanced mechanical advantage to originate a required pre-load force without the necessity of having to generate a large hydraulic force that would otherwise be needed.

Abstract: According to the present invention, there is provided a device for guiding a tool on a string within a blow out prevention ("BOP") stack. In one embodiment, the device includes a top collar connected to a bottom collar by a shroud having a plurality of flexible members which bow outwardly from the collars, wherein the shroud covers a portion of the tool. An energy absorbing bumper is provided above the top collar to absorb structural impact caused by a blow out or other inadvertant pressure in a downhole application.

Abstract: A wellhead retrieval tool assembly for retrieving a check valve has a spear formed as a solid ring at the bottom with free fingers extending upward. The fingers are resilient and have protrusions adapted to engage a retrieval groove in the check valve. A wedge ring is provided on the tool body to positively lock the fingers in radially outward engagement with the retrieval groove. The wedge ring is fixed to the body by a shear pin so that upon a predetermined axial force the pin shears and releases the wedge allowing withdrawal of the tool assembly.

Abstract: The invention relates to apparatus for protecting wellhead bores during drilling operations, and more particularly to bowl protectors for preventing damage to wellhead bore seal surfaces as drilling equipment passes through the wellhead. The invention includes a bowl protector and a seperable false bowl for accepting a casing hanger, the bowl protector and false bowl being releasably connected together by shear pins.

Abstract: A stem-operated fire-resistant gate valve including an improved metal-to-metal stem backseat fusible ring assemblies for facilitating automatic stem backseating at pre-selected temperatures, spring enhancement of the backseating procedure, and an improved metal-to-metal gate seat.

Abstract: A multi-purpose metal-to-metal seal system providing fluid-tight integrity at the area of contact between the seal element and the surface against which it bears, throughout wide variations in pressure and temperature, and especially during and following exposure to a fire atmosphere.

Abstract: A test plug for use in pressure testing a Christmas tree and blowout preventer atop an oil or gas wellhead. The test plug includes a cylindrical body having an outer diameter slightly smaller than the bore of the wellhead, and a plurality of support dogs that fit into an annular groove in the wellhead to support the plug during pressure testing. The plug is landed on a relatively narrow shoulder in the bore of the wellhead and the dogs are then extended into the groove by vertical movement of a mandrel, thereby lifting the plug off the shoulder and securely supporting it in test position.