Abstract: Wellhead assembly and method for providing a power connection to a downhole electrical device, such as a heater. Pressure-containing wellhead body members enclose a vertical wellbore and support therein an isolated tubing hanger and a grounding tubing hanger. The isolated tubing hanger suspends a conducting tubing string, while the grounding tubing hanger suspends a grounding tubing string concentrically spaced from the conducting tubing string. The isolated tubing hanger has an outer housing, an inner electrically conducting portion supported by the outer housing operative to provide electrical connection with, and suspend, the conducting tubing string, and insulation between the housing and conducting portion to electrically isolate the housing portion. Hot electrical connection is made for electrical connection to the conducting portion of the isolated tubing hanger or the conducting tubing string.

Abstract: Wellhead assembly and method for providing power connection to downhole electrical device. Wellhead body members support vertically stacked isolated tubing hanger and grounding tubing hanger. The isolated tubing hanger suspends a conducting tubing string, while the grounding tubing hanger suspends a grounding tubing string concentrically spaced from the conducting tubing string. The isolated tubing hanger has an outer housing, an inner electrically conducting portion supported by the outer housing to provide electrical connection with, and suspend, the conducting tubing string, and insulation between the housing and conducting portion to electrically isolate the housing. Hot electrical connection is made through a conduit in the wellhead body member, for electrical connection to the conducting tubing string. Grounding connection is provided to the wellhead body members.

Abstract: A gate valve for controlling fluid flow, in which a valve body forms a cylindrical flowbore and includes a gate cavity intersecting the flowbore to provide opposed openings into the flowbore. Seat pockets are formed in the opposed openings, each with a radial base and a side wall, and may optionally include metal carrier ring sealed in the seat pockets. The gate is slidably movable within the valve body between open and closed positions. Annular seat elements are mounted in each seat pocket for limited axial movement on opposite sides of the gate, with a first seal surface for sealing against the seat pocket or optional carrier ring, and a second seal surface for sealing against the gate. A non-metallic bridging seal formed as a face seal is provided between the first seal surface of the annular seat element and the seat pocket (or optional carrier ring).

Abstract: Wellhead assembly and method for providing a power connection to a downhole electrical device, such as a heater. Pressure-containing wellhead body members enclose a vertical wellbore and support therein an isolated tubing hanger and a grounding tubing hanger. The isolated tubing hanger suspends a conducting tubing string, while the grounding tubing hanger suspends a grounding tubing string concentrically spaced from the conducting tubing string. The isolated tubing hanger has an outer housing, an inner electrically conducting portion supported by the outer housing operative to provide electrical connection with, and suspend, the conducting tubing string, and insulation between the housing and conducting portion to electrically isolate the housing portion. Hot electrical connection is made for electrical connection to the conducting portion of the isolated tubing hanger or the conducting tubing string.

Abstract: The invention provides a casing adapter tool which connects and seals to a casing pipe at its lower end and to production or service equipment at its upper end, and is used with well servicing equipment, such as is involved in fracturing. The casing adapter tool includes a generally tubular casing adapter body having an upper end and a lower end, and is formed with a central bore extending therethrough. The central bore provides a profile which forms a casing seal chamber at the lower end, and a barrier seal chamber located thereabove. The barrier seal chamber is formed with a profile to accommodate and seal to a first removable pressure barrier on removal of any well servicing equipment. Most preferably, the barrier seal chamber has a profile sized to provide full bore access to the casing pipe and to accommodate and seal to the first removable pressure barrier which is of a threaded, latched or snap ring type check valve or plug.

Abstract: Wellhead assembly and method for providing a power connection to a downhole electrical device, such as a heater or pump. Pressure-containing wellhead body members enclose a vertical wellbore and support, in vertically stacked relationship, an isolated tubing hanger and a grounding tubing hanger. The isolated tubing hanger suspends a conducting tubing string, while the grounding tubing hanger suspends a grounding tubing string concentrically spaced from the conducting tubing string. The isolated tubing hanger has an outer housing, an inner electrically conducting portion supported by the outer housing operative to provide electrical connection with, and suspend, the conducting tubing string, and insulation between the housing and conducting portion to electrically isolate the housing portion. A conduit in a wellhead body member provides access to the vertical wellbore proximate the isolated tubing hanger.

Abstract: The invention provides a Y-body Christmas tree for use with coil tubing and other wellhead components which integrates components of a Christmas tree, while providing for coil tubing access without necessarily adding to the vertical height of the unit. The Y-body Christmas tree includes firstly, a body formed as a single piece of steel and forming a vertical bore extending axially therethrough, wherein the body comprises in sequence from the bottom to the top: i) a bottom connector for connecting to a wellhead component located therebelow; ii) a first valve housing section forming a side opening communicating with the vertical bore; iii) a flow tee housing section forming at least one side opening communicating with the vertical bore, for producing well flow; and iv) a top connector for connecting to a wellhead component located thereabove.

Abstract: A connector head, for transferring at least a portion of the load from an inner tubular body onto an outer tubular body, comprises a generally tubular connector head formed with a central bore through which the inner tubular body extends. The connector head has an inwardly extending stop shoulder to allow the connector head to rest on the upper end of the inner tubular body. A slip connecting means is located in the connector head for gripping the outer wall of the inner tubular body. A base plate, formed with a central bore therethrough, is located below the connector head and is adapted to rest on the upper end of the outer tubular body. A retainer ring, formed with a central bore therethrough, is located between the connector head and the base plate and includes a plurality of threaded stud members extending therethrough allowing the retainer ring to slide upwardly and downwardly on the threaded stud members.

Abstract: A monolithic pumping tree combining a bottom connection, production blow-out preventer section, flow tee section and top connection is cast so as to provide an access port extending downwardly through the side wall of the tree from its outer surface, to connect with either the central vertical bore of the tree or its horizontal bottom surface, thereby enabling coiled tubing to be inserted either into the tubing string bore or into the annulus between the tubing and production casing strings.

Abstract: In the hydraulic blowout preventer of an integral production wellhead, the ram chambers and hydraulic fluid supply line are both buried or formed in the side wall of the blowout preventer.

Abstract: An axial recess is formed in the downstream end of the diffuser body. An annular tail member is mounted on the downstream end of the valve piston. The tail member retracts into the recess when the piston is in the closed position and provides an extension of the diffuser body when the piston is in the open position.

Abstract: The rubber layer on the ram is reinforced at the sealing areas by forming ribs on the ram core. The ribs function to resist extrusion of the rubber layer when the blowout preventer is subjected to high pressure from the well.