Abstract: A seal for a wellhead housing employs a locking groove. The seal is of a U-shape, having an inner and outer radially spaced apart legs. An energizing ring is stroked downward to force the legs apart to cause them to seal between the wellhead housing in the conduit and the wellhead housing. At least one groove is located on one side of the energizing ring, with the groove being of a saw-toothed shape to allow entry but to resist upward movement of the energizing ring. In a metal version of a seal, the groove is located on the exterior of the energizing ring so as to allow some axial movement of the inner leg of the seal relative to the energizing ring. In a second version, the seal is of plastic.

Abstract: A wear bushing assembly for a subsea well to protect a casing hanger during drilling latches by use of a collet. The wear bushing includes a tubular member which lands on the upper end of the casing hanger. A metal collet secures to the wear bushing. The collet has slots in it so as to allow it to radially deflect. The collet has an external shoulder which snaps into and latches in a profile formed in the casing hanger. The collet may serve as a protective portion of the wear bushing.

Abstract: A seal for an oil well apparatus has reinforcing rings embedded within the seal. The seal is elastomeric. The apparatus has an energizing device that deforms the seal to cause it to move radially outward to a set condition. The reinforcing ring does not expand during this radial movement. The reinforcing ring is preferably a cable and is located near the inner diameter of the seal. The seal may also have anti-extrusion rings at the outside corners, which are flexible coil springs. Each anti-extrusion ring is a coil spring with a core of material that has a hardness greater than the hardness of the body of the seal.

Abstract: A subsea well assembly has a cement port closure sleeve which opens and closes a cement port in an outer wellhead housing. The outer wellhead housing secures to conductor pipe. An inner wellhead housing is lowered into the outer wellhead housing before the well is drilled past the conductor pipe, and without having any casing secured to the inner wellhead housing. The sleeve opens and closes an inner return port that extends through the inner wellhead housing and which registers with the outer return port once the inner wellhead housing is in place. Drilling through the inner wellhead housing takes place with the sleeve closed. Subsequently, when casing is run, the casing hanger will engage the sleeve and move it to an open position. This allows cement returns to flow out the inner and outer return ports.

Abstract: A split wear bushing for a subsea well assembly provides a standoff for the drill pipe to avoid damage to the casing near where it secures to the casing hanger. The split wear bushing has an outer wear bushing that locks into the casing hanger. An inner wear bushing lands in the bore of the outer wear bushing. The inner wear bushing has an inner diameter that is smaller than the inner diameter of the casing to provide a standoff. The inner wear bushing is carried on a wear bushing sub. An engaging shoulder on the wear bushing sub contacts the inner wear bushing during each trip of the drill string to pull the inner wear bushing from the outer wear bushing. The inner wear bushing relocks to the outer wear bushing on the return trip. A retrieval lock enables the outer wear bushing to be retrieved along with the inner wear bushing for the final trip.

Abstract: A subsea well having inner and outer tubular housings has features to reduce bending movement of the inner housing within the outer housing. The inner and outer housings have mating wedging surface axially spaced apart from each other. These tapered surfaces are spaced so as to cause the inner housing to wedge within the outer housing as it is lowered into place. A latch latches the inner housing to the outer housing once lowered into place. A sleeve of elastomeric material locates on the exterior of the lower extension of the inner housing. This sleeve extends downward a selected distance to prevent bonding of cement to the inner housing in this area. Part of the latch is mounted to a ring clamp that releasably mounts to the outer housing.

Abstract: A device for retaining tubular inner and outer members together in a well allows the members to be pulled apart with a sufficient shear out force. The members have mating retaining and reaction groooves. The retaining groove has a deeper portion joining a shallower portion which is bounded by a shearing side wall. The reaction groove has a shearing side wall which opposes the shearing side wall of the retaining groove when the inner and outer members are fully inserted together. A solid elastomeric ring is carried within the retaining groove. The ring locates in the deeper portion when the inner and outer members are being pushed together. When a pulling apart force is applied, the shallower portion slides relative to the ring until the ring locates in the shallower portion and is contacted by the opposed shearing side walls.

Abstract: A supporting mechanism for a casing hanger improves the load withstanding ability. The casing hanger is located in a wellhead housing. A recess is formed in the bore of the wellhead housing with an upward facing shoulder extending into the bore. An insert ring is stationarily and rigidly mounted in this recess. The insert ring has a load shoulder on its upper side. The load shoulder of the insert ring is considerably less in width than the recess shoulder. However, the insert ring has a greater hardness to increase the capacity of the insert ring. The casing hanger has an exterior load ring that lands on the insert ring. The load ring has threads which are cut to have clearances initially between the load flanks. A clearance also exists between the upper end of the load ring and a downward facing shoulder on the casing hanger.

Abstract: The invention disclosed herein includes a method and apparatus for latching a temporary guide base to a permanent guide base as the permanent guide base is raised, whereby the two guide bases may be retrieved simultaneously. The apparatus includes a socket means in each guideline of the temporary guide base and a latch means in the base of each guidepost of the temporary guide base. When the permanent guide base is lowered, the latch means passes over the socket means. When the permanent guide base is raised, however, the latch means engages the socket means and the temporary guide base is raised.

Abstract: Method for completing an underwater well includes locating drilling apparatus at the well site, and installing conductor casing in the floor of the body of water with a wellhead, blowout preventer stack, and riser attached thereto at a point near the floor, with the riser extending upwardly to the drilling means. A drill string and standard 171/2 inch drill bit is then run through the wellhead and conductor casing, and a hole is drilled for suspending 16 inch casing within the wellhead and conductor casing. A hanger-support member having a casing string attached thereto is lowered into the well until it lands in the wellhead, and it is then rotated less than 360.degree. to connect it within the wellhead. The hanger-support member is then latched within the wellhead. A hole is then drilled for suspending another casing within the wellhead, and a casing hanger with casing string is run through the riser and into the wellhead, and the casing hanger is landed on the hanger-support member.

Abstract: A breech block hanger support member for a subsea wellhead assembly for wells having a working pressure up to approximately 15,000 psi. The assembly includes a wellhead, the support member, a packoff for sealing the support member, and one or more other casing hangers supported by the support member. The support member is connected to the wellhead for itself suspending casing, for supporting at least one other casing hanger and casing, and for containing the working pressure. Breech block teeth are provided on the wellhead and support member to permit the support member to be stabbed into the wellhead and rotated less than 360.degree. for completing the connection therebetween. The teeth include groupings of spaced-apart no-lead teeth having slots therebetween. The slots provide a flow way for passing well fluids. The support member further includes an upper annular flange for arresting its downward movement within the wellhead. This flange includes flutes aligned with the slots for passing well fluids.

Abstract: In a hydraulic subsea control system having two separate redundant subsea control pods in which each pod is supplied with a hydraulic power supply line and a plurality of fluid control lines by surface controls. The improvement in means for alternately connecting and disconnecting the fluid control lines to each pod. Coacting quick disconnect couplings having first and second portions are positioned between the surface controls and each of the sets of fluid control lines to each pod. Each coupling portion includes a valve whereby when the first and second portions are engaged the valves permit fluid flow and when they are disengaged shut off fluid flow. First and second junction plates are connected between the surface controls and the connected fluid control lines and a hydraulic cylinder and piston assembly is connected between the first and second plates for alternately connecting and disconnecting the couplings to each pod whereby the two pods are controlled separately, but redundantly.