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 diverter for diverting a fluid from a riser in a drilling system. The diverter includes a diverter support housing comprising a suspension structure configured so that the diverter support housing is suspendable from a drilling rig, and a main passage arranged to extend from an uppermost end of the diverter support housing to a lowermost end of the diverter support housing. The main passage is configured to have a drill string extend therethrough. A diverter housing is arranged in the main passage. An annular packer element is mounted within the diverter housing. An actuator is mounted within the diverter housing. The actuator is configured to force the annular packer element into a sealing engagement with the drill string. A seal locking mechanism is configured to retain a tubular sealing element in the diverter housing adjacent to the annular packer element.

Abstract: An apparatus for drilling a subterranean wellbore using a drill string. The apparatus includes a riser, a sealing device arranged in the riser so as to form a first riser chamber and a second riser chamber, and a riser booster pump. The riser at least partly contains the drill string and defines a substantially annular space around the drill string. The second chamber is in a fluid communication with the riser booster pump so that a kill fluid stored in the second riser chamber may be maintained at a first pressure which is greater than a second pressure of a drilling fluid in the first riser chamber.

Abstract: A connector assembly for connecting a hose to a tubular element. The connector assembly includes a housing, a hose connector, and a latch. The housing encloses a main passage which is parallel to a longitudinal axis of the housing and which has a side passage extending through the housing from an exterior of the housing into the main passage. The side passage extends through a connector tube mounted on an exterior of the housing. A hose connector is secured to an end of the hose and engages with the connector tube to connect the hose to the tubular element. The hose connector comprises a pipe portion which mates with the connector tube to connect an interior of the hose to the side passage. The latch urges the connector tube and the pipe portion into engagement and prevents a separation thereof.

Abstract: A diverter for diverting a fluid from a riser in a drilling system. The diverter includes a diverter support housing comprising a suspension structure configured so that the diverter support housing is suspendable from a drilling rig, and a main passage arranged to extend from an uppermost end of the diverter support housing to a lowermost end of the diverter support housing. The main passage is configured to have a drill string extend therethrough. A diverter housing is arranged in the main passage. An annular packer element is mounted within the diverter housing. An actuator is mounted within the diverter housing. The actuator is configured to force the annular packer element into a sealing engagement with the drill string. A seal locking mechanism is configured to retain a tubular sealing element in the diverter housing adjacent to the annular packer element.

Abstract: A pressure containment device for sealing around a tubular body comprising an actuator assembly and a seal assembly, the actuator assembly being operable to engage with the seal assembly to prevent significant rotation of the seal assembly with respect to the actuator assembly and to force the seal assembly into sealing engagement with a tubular body mounted in the pressure containment device, the seal assembly comprising a tubular seal sleeve having a radially inward portion made from a non-elastomeric polymer, and a radially outward portion made from an elastomer.

Abstract: A method of operating a system for handling an influx of gas into a marine riser during the drilling of a well bore includes the steps of operating a first riser closure apparatus to close the riser at a first point above a flow spool provided in the riser, there being a riser gas handling line extending from the riser at the flow spool to a riser gas handling manifold, operating a second riser closure apparatus to close the riser at a second point below the flow spool, pumping fluid into an inlet line which extends into the riser at a point above the second point but below the flow spool, and operating a choke provided in the riser gas handling manifold to maintain the pressure in the inlet line or the riser at a substantially constant pressure.

Abstract: An apparatus for drilling a subterranean wellbore using a drill string. The apparatus includes a riser, a sealing device arranged in the riser so as to form a first riser chamber and a second riser chamber, and a riser booster pump. The riser at least partly contains the drill string and defines a substantially annular space around the drill string. The second chamber is in a fluid communication with the riser booster pump so that a kill fluid stored in the second riser chamber may be maintained at a first pressure which is greater than a second pressure of a drilling fluid in the first riser chamber.

Abstract: A method of operating a drilling system for drilling a subterranean bore hole. The drilling system includes a drill string which rotates during a drilling, and a sealing device which provides a substantially fluid tight seal around the drill string while the drill string is rotating during the drilling. The method includes injecting a fluid into an annular volume around the drill string directly above the sealing device, and controlling a first fluid pressure in the annular volume around the drill string above the sealing device so that the first fluid pressure is greater than a second fluid pressure in the annular volume around the drill string directly below the sealing device.

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: 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 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 fluid pressure operated actuator assembly comprising a tubular body (110) having a wall, with an interior surface and an exterior surface and enclosing a main passage (112) which extends generally parallel to a longitudinal axis of the tubular body, an actuator (118) located in and movable along the main passage, a first direction chamber (138a) formed between the wall of the tubular body and the actuator, and at least one second direction chamber (138b, c) formed between the tubular body and the actuator, wherein the assembly is configured such that when the pressure of fluid in the first direction chamber exceeds the pressure of fluid in the or each second direction chamber by a predetermined amount, the pressure of fluid in the first direction chamber exerts a force on the actuator which acts to push the actuator in a first direction relative to the tubular body, and when the pressure of fluid in the or at least one of the second direction chamber(s) exceeds the pressure of fluid in the first direction c

Abstract: A connector assembly for connecting a hose to a tubular element. The connector assembly includes a housing, a hose connector, and a latch. The housing encloses a main passage which is parallel to a longitudinal axis of the housing and which has a side passage extending through the housing from an exterior of the housing into the main passage. The side passage extends through a connector tube mounted on an exterior of the housing. A hose connector is secured to an end of the hose and engages with the connector tube to connect the hose to the tubular element. The hose connector comprises a pipe portion which mates with the connector tube to connect an interior of the hose to the side passage. The latch urges the connector tube and the pipe portion into engagement and prevents a separation thereof.

Abstract: A method of drilling a subterranean bore hole comprising a) pumping a drilling fluid down a drill string, the drill string having a drill bit at an end thereof, b) rotating the drill string about its longitudinal axis to that the bit forms bore hole in the ground, the method further comprising the steps of: c) changing the rate of pumping of the drilling fluid into the drill string in response to a change in the speed of rotation of the drill string, and/or changing the speed of rotation of the drill string in response to a change in the rate of pumping of the drilling fluid into the drill string.

Abstract: A method of drilling a subterranean wellbore using a drill string including the steps of estimating or determining a reduced static density of a drilling fluid based on the equivalent circulating density of the drilling fluid in a section of the wellbore, providing a drilling fluid having substantially that reduced static density, introducing the drilling fluid having said reduced static density into the wellbore, and removing the drilling fluid from the wellbore via a return line.

Abstract: A slip joint (10) having a tubular inner barrel (11b) and a tubular outer barrel (11a), the inner barrel (11b) lying at least partially within the outer barrel (11a), the slip joint further comprising a sealing assembly (12a), (12b), (12c) which is operable to provide a substantially fluid tight seal between two sealing surfaces comprising an interior surface of the outer barrel 11a and an exterior surface of the inner barrel (11b), the sealing assembly (12a), (12b), (12c) including an actuator (20) and a seal (46), the actuator (20) being movable to push the seal (46) into engagement with one of the sealing surfaces.

Abstract: A drilling system including a riser, a pressure vessel, a source of pressurized gas, and a main flow line which extends from the riser to the pressure vessel, the pressure vessel having a liquid inlet port connected to the main flow line, a gas inlet port connected to the source of pressurized gas, a liquid outlet port located in a lowermost portion of the pressure vessel, and a gas outlet port located in an uppermost portion of the pressure vessel.

Abstract: A blow out preventer (BOP) for use in the drilling of a wellbore into a subterranean fluid reservoir and/or the production of fluid is provided. The BOP includes a housing having longitudinal axis and being divided into a first housing part and a second housing part, movement of the first housing part relative to the second housing part being prevented by fasteners, each fastener including a shaft which extends through a fastener receiving passage provided in the first housing part into a fastener receiving passage provided in the second housing part. The housing is further provided with fluid flow passages which extend from the first part of the housing to the second part of the housing, the fluid flow passages being interspersed between fastener receiving passages.

Abstract: A valve assembly comprising a body having a main passage, and a valve member which is located in the main passage and which is rotatable between an open position in which the main passage is substantially open, and a closed position in which the valve member substantially blocks the main passage, and an actuator which is movable generally parallel to the longitudinal axis of the main passage, the actuator being engaged with the valve member such that movement of the actuator generally parallel to the longitudinal axis of the main passage causes the valve member to rotate between its open and closed positions.

Abstract: A drilling system including a drill string (12) which extends into a borehole (10), and a well closure system which contains fluid in the annular space (16) in the borehole around the drill string, the well closure system having a side bore whereby controlled flow of fluid out of the annular space in the borehole around the drill string is permitted, the side bore being connected to fluid return line (28) which extends from the side bore to a fluid reservoir (34), there being provided in the fluid return line a valve (30a) which is operable to restrict flow of fluid along the fluid return line to variable extent, and a flow meter (32) operable to measure the rate of flow of fluid along the fluid return line, the flow meter being located between the valve and the side bore, wherein a filter (40) is provided between the flow meter and the side bore, the filter including a plurality of apertures which have a smaller cross-sectional area than the smallest fluid flow lines in the flow meter.