Abstract: This invention provides apparatus and methods for controlling the particle size of the solid mass present in the circulating drilling fluid returning from an underwater wellhead during the drilling of a subsea wellbore. The system may include a separator at the sea floor adjacent the wellhead, which separates solids above a predetermined size from the wellstream. The wellstream then enters one or more underwater pumps, which pump the wellstream to the surface. A crusher, as a separate unit, integrated in the separator or in the pump, receives the separated solids and reduces them to relatively small-sized particles. The small particles are then pumped or moved to the surface by the pumps utilized for pumping the wellstream to the surface or by a separate underwater pump. Alternatively, the separated solids are collected from the separator into a container, which container is then transported to the surface by a suitable method.

Abstract: The present invention provides drilling systems for drilling subsea wellbores. The drilling system includes a tubing that passes through a sea bottom wellhead and carries a drill bit. A drilling fluid system continuously supplies drilling fluid into the tubing, which discharges at the drill bit bottom and returns to the wellhead through an annulus between the tubing and the wellbore carrying the drill cuttings. A fluid return line extending from the wellhead equipment to the drilling vessel transports the returning fluid to the surface. In a riserless arrangement, the return fluid line is separate and spaced apart from the tubing. In a system using a riser, the return fluid line may be the riser or a separate line carried by the riser. The tubing may be coiled tubing with a drilling motor in the bottom hole assembly driving the drill bit.

Abstract: The present invention provides drilling systems for drilling subsea wellbores. The drilling system includes a tubing that passes through a sea bottom wellhead and carries a drill bit. A drilling fluid system continuously supplies drilling fluid into the tubing, which discharges at the drill bit bottom and returns to the wellhead through an annulus between the tubing and the wellbore carrying the drill cuttings. A fluid return line extending from the wellhead equipment to the drilling vessel transports the returning fluid to the surface. In a riserless arrangement, the return fluid line is separate and spaced apart from the tubing. In a system using a riser, the return fluid line may be the riser or a separate line carried by the riser. The tubing may be coiled tubing with a drilling motor in the bottom hole assembly driving the drill bit.

Abstract: A tubing handling for subsea oilfield tubing operations, includes an isolation tube to mechanically and/or chemically protect the drill string and improved passage of the drill string and fluid return line to the drilling vessel that further protects them during drilling use. In addition, the improvements include an automatic safety apparatus to hold against unintended movement of the tubular members under extreme length and weight conditions as well as against human error at the rig. Further, the invention includes multi-segment coiled tubing drill strings that can be adapted to drilling requirements in a deep wellbore.

Abstract: The present invention provides a drilling system that utilizes an integrated bottom hole assembly. The bottom hole assembly contains sensors for determining the health of the bottom hole assembly, borehole condition, formation evaluation characteristics, drilling fluid physical and chemical properties, bed boundary conditions around and in front of the drill bit, seismic maps and the desired drilling parameters that include the weight on bit, drill bit speed and the fluid flow rate. A downhole processor controls the operation of the various devices in the bottom hole assembly to effect changes to the drilling parameters and the drilling direction to optimize the drilling effectiveness.

Abstract: The present invention provides apparatus and method for killing or suppressing a subsea wellbore. The system includes a pressure intensifier adjacent the wellhead. The output of the pressure intensifier is coupled to a “kill” inlet at the wellhead equipment. Power is supplied from the surface to the pressure intensifier, which increases the pressure by a known multiple, usually 3 to 5, and supplies the high pressure fluid to the wellbore. A control unit at the surface controls the operation of the pressure intensifier in response to the predefined criteria or programmed instructions. One or more sensors provide measurements to the control unit of the wellbore conditions, which are used to determine the timing of activation of the pressure intensifier.

Abstract: A drillstring pressure-modulation valve which is usable in combination with a downhole drilling motor and a drillstring thruster to compensate for changes in pressure drop through the drilling motor which normally occur during drilling. When conditions change during drilling, which in turn changes the pressure drop through the drilling motor, the drillstring pressure-modulation valve compensates for such changes to minimize the effect of such changes on the operation of the thruster and the resulting WOB created by the thruster. The modulation valve has a feature which allows it to find automatically a balanced preload condition for the main needle valve, the primary functional element within the modulation valve, each time the rig pumps are turned off and then turned on. The modulation valve is fully self-contained, and is assembled as part of the bottomhole assembly.