W-k-m Wellhead Systems, Inc.

Cooper Industries, Inc.

Acf Industries, Incorporated

Joy Manufacturing Company

Robert J Diehl

William L Godare

Danny S Meyer

Robert C Houlgrave

F Harold Hollister

Roger S Osborne

James T Carmichael

Frederic D Wells, Jr

Jeff Elwood

An enclosed protective chamber for a subsea wellhead assembly includes a main body installed on the sea floor. Subsea wellhead apparatus is mounted in the chamber on top of a well. A pressure-containing lid is mounted on and sealed with respect to the main body such that chamber pressure is isolated from the subsea hydrostatic head. An inflatable, elongated, flexible storage tank or dracon is attached to the chamber through a conduit having a pressure-balanced relief valve therewithin. The dracon is attached to the conduit through a quick disconnect coupling and closure valve which permit ready attachment, removal, or replacement of the dracon. Under normal operating conditions the dracon is deflated. The dracon is preferably anchored to the sea floor. When a leak in the subsea wellhead assembly occurs, excess chamber pressure permits surplus fluid to enter and fill the dracon. The dracon may then be disconnected from the conduit, the anchor released, and the dracon removed to the surface for retrieval or disposal of the fluid contents. Substantially no well or chamber fluids ar released into the sea during the dracon removal and reinstallation processes. A pop-off cap and expandable conduit may be mounted on top of the chamber.

Environmental protection for subsea wells

A 'fire-resistant' packing arrangement (30) for use with linear motion or rotary motion shafts (20) characterized by a stepped dual diameter packing chamber provided by successive enlargements of the stem bore (22). A primary packing assembly (31) disposed in the chamber section (20b) of smaller diameter and cross-sectional areas and located nearest the fluid pressure provides for sealing under normal temperature and operating conditions. A secondary packing assembly (32) in the larger diameter chamber section (20c) and fabricated of 'high temperature' materials is adapted to maintain sealing effectiveness in the event of abnormally high temperatures. A packing support ring (35) disposed in the larger diameter chamber section (20c) intermediate the two packing assemblies and supportable on the shoulder (62) provided by the stem bore enlargement, supports the secondary packing (32) and in the event of a decomposition of the primary packing (51) induced by extreme temperature conditions permits the secondary 'high temperature' packing to maintain a seal. A packing retainer ring (38) located at the outer end of the packing arrangement as an outer packing stop is axially adjustable to provide a preload energization of the primary packings.

Dual diameter valve stem packing

A wellhead sealing assembly comprising a metallic sealing ring (10) which is compressed and deformed by tubing hanger load and fluid pressure to establish metal-to-metal sealing contact with the tubing hanger (20) and the tubing head (30). The outer surface of the sealing ring includes an upper cylindrical surface (11) and a lower downward facing frusto-conical surface (16) which coact respectively, with the bore wall of the tubing head (30) and an upward facing frusto-conical shoulder (33) in the tubing head bore (32). It is also provided with an annular end surface (13) which is radially transverse to the ring axis and coacts with a corresponding downward facing shoulder (22) on the tubing hanger (20) which seats thereagainst. The metallic ring (10) also comprises inner annular surfaces in the form of an upward facing frusto-conical surface (15) and a lower cylindrical surface (12) which coacts respectively with a downward facing frusto-conical surface (23) and a cylindrical surface (24) on a reduced diameter section of the tubing hanger. When the tubing hanger is seated on the upper end surface (13) of the sealing ring (10), there is a 5.degree. difference in the angles of taper between the inner frusto-conical surface (15) of the sealing ring (10) and the outer frusto-conical surface (23) of the tubing hanger (20) with the two frusto-conical surfaces contacting only at their upper extremities. When compression loads are applied, the sealing ring is compressed and deformed radially to coact and establish sealing metal-to-metal contact with the bore (32) of the tubing head (30) and the external tapered and cylindrical surfaces (23, 24) of the tubing hanger 20.

Seal assembly

A packing support assembly (10) adapted to be sleeved about a well casing ('C'), or the like, and secured thereto without the need for piercing the casing wall or welding thereto. The support assembly (10) comprises an anchor ring (11) which is sleeved about the casing ('C') and secured thereto by a first fastening means in the form of a plurality of circumferentially located fastening means such as radial bores (22) and set screws (31). The anchor ring (11) is provided with flexible fingers (61) having ridged surfaces (16) which are also adapted to rip the external wall of the casing ('C'). The flexible fingers (61) are wedged inwardly to grip the casing ('C') by means of a retainer ring (71) which is threaded onto the exterior of the anchor ring (11) and provided with an internal wedging surface (75) which is slidably engageable with cooperating wedging surfaces (52) on the exterior of the flexible fingers (61) of the anchor ring (11 ). The gripping force is adjustable as determined by the degree of turning of the set screws (31) and the amount of rotation and threaded connection of the retainer ring (71) on the anchor ring (11). The upper annular edge (81) of the retainer ring is configured to support and retain an annular packing, or the like, thereon.

Packing support for mounting a well casing packing

A packing assembly is mounted in the annular space between a tubing hanger and a tubing head of a wellhead assembly. The packing is bottomed on a shoulder of the tubing hanger and energized after the tubing hanger has been fully seated within the tubing head by the injection of a lubricant or the like against an upper annular piston member which compresses the packing. The piston member is locked to the tubing hanger after the packing has been compressed between the facing annular surfaces of the tubing head and tubing hanger and the entire packing assembly then moves with the tubing hanger.

Packing assembly for wellheads

A cyclone type steam separator (10) having a square inlet opening (46) which may be adjusted in size by means of an inlet control device (20). The device includes a rigid body (62) having perpendicular arms which form two sides of the square opening. The other two sides are formed by sliding bars (108 and 110) which are connected slidably with the arms and which overlap with one another to define a stationary corner of the opening. The body may be adjusted to vary the effective length of each side of the opening, with one side remaining on the outer side of the inlet conduit to direct the incoming fluid into the steam separator along the inside surface of the separator vessel.

Steam separator with variably sized rectangular inlet opening

A mechanism for releasably holding down a tubing hanger received within a hanger bowl of a wellhead. Pins mounted for axial sliding movement in horizontal passages of the hanger bowl are forced inwardly by screws which are threaded into passages of the wellhead and against heads formed on the outer ends of the pins. The pins have tapered inner ends which are forced into a groove of the tubing hanger and against a camming surface of the groove in order to press the tubing hanger downwardly within the hanger bowl. Each screw has a blade on its inner end which enters a slot in the head of the corresponding pin to rotate the pin as it is pushed against the camming surface of the groove. Springs urge the pins outwardly to facilitate entry of the blades into the slots, and retainer rings maintain the pins in their passages in the hanger bowl.

Holddown mechanism for a tubing hanger in a wellhead

A tool for removing and replacing wing valves or master valves on an operating wellhead under pressure includes an elongated housing with a fluid coupling on one end for connecting to the outlet end of a wellhead valve and a packing assembly extending from the housing through the valve into the wellhead where it seals fluid flow to the valve. A latch on the packing assembly is used to secure it in the wellhead. The housing is equipped with a manipulator to expand and retract the packing and to engage and release the latch. An auxiliary reaming tool is provided for mounting with the manipulator and inserting through the valve to smooth the bore of a wellhead conduit if necessary prior to inserting the packing assembly into the conduit.

Wellhead valve removal and installation tool

A limited float or controlled float seat assembly for a gate valve with a transversely expandable gate assembly has generally L-shaped annular seat retainers fixed in recesses around the valve inlet and outlet flow passageways and generally L-shaped annular seat members mounted in a complementary relation within each of the seat retainers. The seat retainers each have an inturned lip opposite to and spaced from the end of the recess. The inturned lips form limit stops for the seat members. The seat members have an outturned lip which contacts the inturned lip of the seat retainer thereby limiting movement of the seat member when the seat member moves to an extended position. The combined amount of float for both seat members is less than the total expansion of the gate assembly from a collapsed position to an expanded position where it seals with the seat members so that drag of the seat members on the gate assembly is minimized.

Growing community of inventors

Wallis, TX, United States of America

Robert J Diehl