摘要:
Methods and control systems are provided for a wellbore drilling system having an active differential pressure device (APD device) in fluid communication with a returning fluid. The APD Device creates a differential pressure across the device, which reduces the pressure below or downhole of the device. In embodiments, a control unit controls the APD Device in real time via a data transmission system. In one arrangement, the data transmission system includes data links formed by conductors associated with the drill string. The conductors, which may include electrical wires and/or fiber optic bundles, couple the control unit to the APD Device and other downhole tools such as sensors. In other arrangements, the data link can include data transmission stations that use acoustic, EM, and/or RF signals to transfer data. In still other embodiments, a mud pulse telemetry system can be used in transfer data and command signals.
摘要:
An active differential pressure device (APD device) in fluid communication with a returning fluid creates a differential pressure across the device, which controls pressure below the APD Device. In embodiments, a control unit controls the APD Device to provide a selected pressure differential at a wellbore bottom, adjacent a casing shoe, in an intermediate wellbore location, or in a casing. In one arrangement, the control system is pre-set at the surface such that the APD Device provides a substantially constant pressure differential. In other arrangements, the control system adjusts an operating parameter of the APD Device to provide a desired pressure differential in response to one or more measured parameters. Devices such as an adjustable bypass can be used to control the APD Device. In other embodiments, one or more flow control devices coupled to the return fluid reduce the effective pressure differential provided by the APD Device.
摘要:
A system for reverse circulation in a wellbore include equipment for supplying drilling fluid into the wellbore bit via at least an annulus of the wellbore and returning the drilling fluid to a surface location via at least a bore of a wellbore tubular. The system also includes devices for controlling the annulus pressure associated with this reverse circulation. In one embodiment, an active pressure differential device increases the pressure wellbore annulus to at least partially offset a circulating pressure loss. In other embodiments, the system includes devices for decreasing the pressure in the annulus of the wellbore. For offshore application, annulus pressure is decreased to accommodate the pore and fracture pressures of a subsea formation. In still other embodiments, annulus pressure is decreased to cause an underbalanced condition in the well.
摘要:
Methods and control systems are provided for a wellbore drilling system having an active differential pressure device (APD device) in fluid communication with a returning fluid. The APD Device creates a differential pressure across the device, which reduces the pressure below or downhole of the device. In embodiments, a control unit controls the APD Device to provide a selected pressure differential at a wellbore bottom, adjacent a casing shoe, in an intermediate wellbore location, or in a casing. In one arrangement, the control system is pre-set at the surface such that the APD Device provides a substantially constant pressure differential. In other arrangements, the control system measures one or more parameters (e.g., wellbore pressure, formation parameters, BHA parameters, etc.) and adjusts an operating parameter of the APD Device to provide a desired pressure differential. Devices such as an adjustable bypass can be used to control the APD Device.
摘要:
Completion method for avoiding formation impairment in the completion of a wellbore by anchoring and activating a plug at a selected position in the wellbore to seal off a selected portion of the wellbore from other portions of the wellbore. The plug is positioned at the selected position in the wellbore and anchored at that position. A seal in the plug is then activated such that fluid cannot pass the plug. Other parts of the wellbore can then be operated at different pressures than the isolated part of the wellbore without impairment of the formation resulting from the loss of well fluids into the formation.
摘要:
An apparatus for injection of coiled tubing or jointed tubulars into a well bore, using an injector head capable of handling either type of tubular. The injector head and a working platform are mounted on a structure over the well head, with the injector being positioned so as to allow personnel access to the tubing on the working platform without having to relocate the injector head away from the well head location. The injector can be mounted below the working platform, or it can be mounted spaced above the working platform on a vertically movable trolley on a mast. When the injector is mounted below the working platform, the tubulars and any bottom hole assembly are accessible to personnel on top of the working platform, whether coiled tubing or jointed tubulars are being used. When the vertically movable trolley is used for coiled tubing operations, the injector head can be lowered to the working platform for injection or pulling operations, and it can be raised above the working platform to give access to the tubing and the bottom hole assembly. When the vertically movable trolley is used for jointed tubular operations, the injector head can be raised above the working platform for all phases, and a movable mandrel can be used in the injector head for raising or lowering the jointed tubulars.
摘要:
One or more components of a wellbore drilling assembly utilize a modular construction to facilitate assembly, disassembly, repair and/or maintenance of a wellbore drilling assembly and/or to extend the overall operating capabilities of the drilling assembly. In one embodiment, a modular construction is used for an APD Device, a motor driving the modular APD Device, a comminution device, and an annular seal. Individual modules can be configure have different operating set points, operating parameters and characteristics (e.g., rotational speeds, flow rates, pressure differentials, etc.) and/or different responses to given environmental factors or conditions (e.g., pressure, temperature, wellbore fluid chemistry, etc.). In one embodiment, the high-pressure seals used in conjunction with the APD Device and/or motor is a hydrodynamic seal that provides a selected leak or flow rates. Optionally, the seal is modular to provide different degrees of leak rates and/or different functional characteristics.
摘要:
The present invention provides drilling systems for drilling wellbores. The drilling system includes an umbilical that passes through a wellhead and carries a drill bit. A drilling fluid system supplies drilling fluid into an annulus (supply line) between the umbilical and the wellbore, which discharges at the drill bit bottom and returns to the wellhead through the umbilical (return line) carrying the drill cuttings. A fluid circulation device, such as a turbine or centrifugal pump, is operated in the return line to provide the primary motive force for circulating drilling fluid through a fluid circuit formed by the supply line and return line. Optionally, a secondary fluid circulation device in fluid communication with the return line can cooperate with the fluid circulation device to circulate drilling fluid and/or a near bit fluid circulation device can be used to provide localized flow control or suction pressure to improve bit cleaning.
摘要:
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. A suction pump coupled to the annulus is used to control the bottom hole pressure during drilling operations, making it possible to use heavier drilling muds and drill to greater depths than would be possible without the suction pump. An optional delivery system continuously injects a flowable material, whose fluid density is less than the density of the drilling fluid, into the returning fluid at one or more suitable locations the rate of such lighter material can be controlled to provide supplementary regulation of the pressure. Various pressure, temperature, flow rate and kick sensors included in the drilling system provide signals to a controller that controls the suction pump, the surface mud pump, a number of flow control devices, and the optional delivery system.