Abstract: A seal assembly for use in a pressure containment device for containing a fluid pressure in an annular space around a drill string whilst allowing the drill string to rotate in the pressure containment device. The seal assembly includes a seal with an inner surface and a tubular body, and a wear sensor embedded in the tubular body of the seal. The wear sensor emits an alert signal when the inner surface of the seal has been worn away by a first preset amount. The alert signal includes a pressure signal and/or a chemical signal.

Abstract: A method of drilling a subterranean wellbore using a drill string includes injecting a drilling fluid into the subterranean well bore via the drill string and removing the drilling fluid from an annular space around the drill string (the annulus) via an annulus return line, oscillating a pressure of the drilling fluid in the annulus, determining a wellbore storage volume and a wellbore storage coefficient for each drilling fluid pressure oscillation, and using the wellbore storage volume and wellbore storage coefficient to determine a proportion by volume of gas and a proportion by volume of liquid in the annulus during that drilling fluid pressure oscillation. The wellbore storage volume is a change in a measured flow rate over a time period. The wellbore storage coefficient is the wellbore storage volume divided by a pressure change over the time period.

Abstract: A riser assembly includes a main body which encloses a main body main passage extending from a first end to a second end which is generally parallel to a longitudinal axis, the main body being mounted in a riser so that that the main body main passage forms a part of a main passage of the riser. A first port and a second port extend through the main body to connect the main body main passage with an exterior of the main body. A tubular extends along the main body main passage. A first sealing assembly is arranged in the main body between the first port and the second port. The first sealing assembly provides a seal between the main body and the tubular. At least two diversion lines extend from the first port to the second port. A pump is arranged within each diversion line.

Abstract: In an embodiment, the present invention provides a pressure containment device which includes a housing with a returns outlet port, an injection port, and an overflow outlet port, and a seal assembly with a seal arranged in the housing to surround and enter into a sealing engagement with a tubular body extending along a passage in the housing via a sealing face. The injection port is arranged between the returns outlet port and a first end of the seal. The overflow outlet port is arranged adjacent to a second, opposite, end of the seal and communicates with an upper end of the passage. The upper end of the passage connects to a bell nipple or to a section of a riser pipe and, in use, the overflow outlet port is exposed to a hydrostatic head provided by a fluid in the bell nipple or the section of the riser pipe.

Abstract: A riser pressure relief apparatus includes a pressure relief valve with a valve member, an actuator, and a pilot valve assembly connected to a pressurized fluid. The valve member moves between a first position, which prevents a fluid flow through the side port, and a second position, which permits the flow. The actuator includes an open port and moves the valve member from the first to the second position by supplying the pressurized fluid to the open port. The pilot valve assembly moves between a first configuration, which prevents a flow of the pressurized fluid to the open port, and a second configuration, which permits the flow. A valve part of the pilot valve assembly moves from a first to a second position based on a fluid pressure in the riser, which causes the pilot valve assembly to move from the first to the second configuration or vice versa.

Abstract: A drilling system for drilling a subterranean well bore includes a controller and a first and a second set of field devices. Each of the first and second set of field devices measure a physical characteristic of the drilling system and to transmit to the controller signals representing a measured value of the physical characteristic. The controller is programmed to use a first set of algorithms to process the signals received from the first set of field devices to determine if the measured values represented by the signals indicate that there might have been an influx of formation fluid into the subterranean well bore, and a second set of algorithms to process the signals received from the second set of field devices to determine if the measured values represented by the signals indicate that there might have been an influx of formation fluid into the subterranean well bore.

Abstract: An apparatus for degassing drilling fluid comprising a primary separator and a secondary separator, the primary separator comprising a vessel body having an inlet port, a liquid outlet port located at a lower end of the vessel body, and a gas vent port located at an upper end of the vessel body, the secondary separator having an inlet port which is connected to the gas vent port of the primary separator, a gas outlet port, and a liquid outlet port which is connected to the interior of the vessel body of the primary separator via a liquid return line.

Abstract: An apparatus for continuous circulation drilling comprising a tubular body having a main passage extending along a longitudinal axis of the tubular body from a first end of the tubular body to a second end of the tubular body, a side passage and a control passage, the side passage and control passage both extending through the tubular body into the main passage, the tubular body containing a valve assembly which is operable to close the main passage when the side passage is open and to close the side passage when the main passage is open, the assembly further comprising a hydraulic connector which is operable to clamp around the tubular body, the connector comprising a housing with an interior surface which is provided with first and second grooves which, when the connector is clamped around the tubular body, each form a channel which extends in continuous loop around the exterior of the tubular body, there being at least one passage extending through the housing from an exterior surface of the housing into e

Abstract: A pressure containment device includes a sealing element. The sealing element includes a longitudinal axis, a substantially annular cross-section arranged perpendicular to the longitudinal axis, a radially inwardly facing interior surface having a plurality of recesses, a radially outwardly facing exterior surface, a first end surface having a plurality of recesses, and a second end surface. The first end surface and the second end surface are each arranged to extend from the radially inwardly facing interior surface to the radially outwardly facing exterior surface. The first end surface and the second end surface are arranged at opposite ends of the sealing element.

Abstract: A method of drilling a subterranean well bore comprising, monitoring the well bore for influx of formation fluid into the well bore, and, on detection of an influx, a) stopping any pump pumping fluid into the well bore, b) operating a first blow out preventer so that it closes within a first period of time, c) operating a second blow out preventer so that it closes within a second period of time, the second blow out preventer being located below the first blow out preventer, the second period of time being longer than the first period of time, d) circulating the influx out of the well bore via a flow line extending from below the second blow out preventer.

Abstract: A seal assembly for use in a pressure containment device for containing a fluid pressure in an annular space around a drill string whilst allowing the drill string to rotate in the pressure containment device. The seal assembly includes a seal with an inner surface and a tubular body, and a wear sensor embedded in the tubular body of the seal. The wear sensor emits an alert signal when the inner surface of the seal has been worn away by a first preset amount. The alert signal includes a pressure signal and/or a chemical signal.

Abstract: A method of drilling a subterranean wellbore using a drill string includes injecting a drilling fluid into the subterranean well bore via the drill string and removing the drilling fluid from an annular space around the drill string (the annulus) via an annulus return line, oscillating a pressure of the drilling fluid in the annulus, determining a wellbore storage volume and a wellbore storage coefficient for each drilling fluid pressure oscillation, and using the wellbore storage volume and wellbore storage coefficient to determine a proportion by volume of gas and a proportion by volume of liquid in the annulus during that drilling fluid pressure oscillation. The wellbore storage volume is a change in a measured flow rate over a time period. The wellbore storage coefficient is the wellbore storage volume divided by a pressure change over the time period.

Abstract: A valve assembly for use controlling flow of fluid into a drill pipe, the valve assembly having a valve body, a valve member and a valve seat, wherein a) the valve body has a main passage b) the valve member is movable between a closed position in which the valve member engages with a seat face of the valve seat to substantially prevent flow of fluid along the main passage, and an open position in which the valve member is spaced from the seat face, c) the valve seat is a separate part to the valve body.

Abstract: A seal assembly for use in a pressure containment device for containing a fluid pressure in an annular space around a drill string while allowing the drill string to rotate in the pressure containment device. The seal assembly includes a seal comprising and an inner surface and a tubular body, and a wear sensor embedded in the tubular body. The wear sensor emits an alert signal when the inner surface of the seal has been worn away by a preset amount.

Abstract: A method of drilling a subterranean wellbore using a drill string comprising the steps of: a. injecting a drilling fluid into the well bore via the drill string and removing said drilling fluid from an annular space around the drill string (the annulus) via an annulus return line, b. oscillating the pressure of the fluid in the annulus, c. determining the wellbore storage volume and wellbore storage coefficient for each fluid pressure oscillation, d. using the wellbore storage volume and wellbore storage coefficient to determine the proportion by volume of gas and proportion by volume of liquid in the annulus during that pressure oscillation.

Abstract: In an embodiment, the present invention provides a pressure containment device which includes a housing with a returns outlet port, an injection port, and an overflow outlet port, and a seal assembly with a seal arranged in the housing to surround and enter into a sealing engagement with a tubular body extending along a passage in the housing via a sealing face. The injection port is arranged between the returns outlet port and a first end of the seal. The overflow outlet port is arranged adjacent to a second, opposite, end of the seal and communicates with an upper end of the passage. The upper end of the passage connects to a bell nipple or to a section of a riser pipe and, in use, the overflow outlet port is exposed to a hydrostatic head provided by a fluid in the bell nipple or the section of the riser pipe.

Abstract: A method of operating a drilling system. The drilling system includes a drill string extending into a wellbore, a driver which rotates the drill string, a pump to pump drilling fluid down the drill string, a wellhead mounted at the wellbore, a riser extending up from the wellhead around the drill string, a blowout preventer mounted on the wellhead, a riser closure device mounted in the riser, a first return conduit, and a flow outlet arranged in the riser below the riser closure device. The method includes operating the driver to stop a rotation of the drill string, closing the riser closure device if it is not already closed, operating the pump to stop a pumping of drilling fluid down the drill string, closing the blowout preventer, and increasing a wellbore pressure by controlling a rate of the flow of the fluid along the first return conduit.

Abstract: A pressure containment device for containing pressure in an annulus around a tubular body, the device comprising a housing having an axis and a passage extending generally parallel to the housing axis, and a seal assembly comprising a seal located in the housing to surround and enter into sealing engagement with a tubular body extending along the passage, wherein the housing is provided with a returns outlet port, an injection port, and an overflow outlet port, all of which extend through the housing from the exterior of the housing into the passage, the injection port being located between the returns outlet port and a first end of the seal, and the overflow outlet port being located adjacent a second, opposite end of the seal, and thus being separated from the injection port by the seal.

Abstract: A riser pressure relief apparatus includes a pressure relief valve with a valve member, an actuator, and a pilot valve assembly connected to a pressurized fluid. The valve member moves between a first position, which prevents a fluid flow through the side port, and a second position, which permits the flow. The actuator includes an open port and moves the valve member from the first to the second position by supplying the pressurized fluid to the open port. The pilot valve assembly moves between a first configuration, which prevents a flow of the pressurized fluid to the open port, and a second configuration, which permits the flow. A valve part of the pilot valve assembly moves from a first to a second position based on a fluid pressure in the riser, which causes the pilot valve assembly to move from the first to the second configuration or vice versa.

Abstract: A riser assembly includes a main body which encloses a main body main passage extending from a first end to a second end which is generally parallel to a longitudinal axis, the main body being mounted in a riser so that that the main body main passage forms a part of a main passage of the riser. A first port and a second port extend through the main body to connect the main body main passage with an exterior of the main body. A tubular extends along the main body main passage. A first sealing assembly is arranged in the main body between the first port and the second port. The first sealing assembly provides a seal between the main body and the tubular. At least two diversion lines extend from the first port to the second port. A pump is arranged within each diversion line.