13843 results about "Well drilling" patented technology

An actively controlled rotary steerable drilling system for directional drilling of wells having a tool collar rotated by a drill string during well drilling. A bit shaft has an upper portion within the tool collar and a lower end extending from the collar and supporting a drill bit. The bit shaft is omni-directionally pivotally supported intermediate its upper and lower ends by a universal joint within the collar and is rotatably driven by the collar. To achieve controlled steering of the rotating drill bit, orientation of the bit shaft relative to the tool collar is sensed and the bit shaft is maintained geostationary and selectively axially inclined relative to the tool collar during drill string rotation by rotating it about the universal joint by an offsetting mandrel that is rotated counter to collar rotation and at the same frequency of rotation. An electric motor provides rotation to the offsetting mandrel with respect to the tool collar and is servo-controlled by signal input from position sensing elements such as magnetometers, gyroscopic sensors, and accelerometers which provide real time position signals to the motor control. In addition, when necessary, a brake is used to maintain the offsetting mandrel and the bit shaft axis geostationary. Alternatively, a turbine is connected to the offsetting mandrel to provide rotation to the offsetting mandrel with respect to the tool collar and a brake is used to servo-control the turbine by signal input from position sensors.

Methods and systems for drilling to a target location include a control system that receives an input comprising a planned drilling path to a target location and determines a projected location of a bottom hole assembly of a drilling system. The projected location of the bottom hole assembly is compared to the planned drilling path to determine a deviation amount. A modified drilling path is created to the target location as selected based on the amount of deviation from the planned drilling path, and drilling rig control signals that steer the bottom hole assembly of the drilling system to the target location along the modified drilling path are generated.

Methods and apparatus for making directional measurements of earth formations surrounding a borehole. New antenna coil shield designs are utilized to provide selective attenuation of at least one electromagnetic energy field component as the component interacts with the shield. The new shields are implemented in several downhole tool configurations to provide azimuthally focused formation measurements. In effect, the new shield filters interacting electromagnetic energy field components to pass those components corresponding to a magnetic dipole oriented at an angle from the tool axis. The shields thereby alter a coil's envelope of influence to electromagnetic energy. The new shields also form part of a system for making directional measurements while drilling.

Apparatus and methods for a deployment valve used with an underbalanced drilling system to enhance the advantages of underbalanced drilling. The underbalanced drilling system may typically comprise elements such as a rotating blow out preventer and drilling recovery system. The deployment valve is positioned in a tubular string, such as casing, at a well bore depth at or preferably substantially below the string light point of the drilling string. When the drilling string is above the string light point then the upwardly acting forces on the drilling string become greater than downwardly acting forces such that the drilling string begins to accelerate upwardly. The deployment valve has a bore sufficiently large to allow passage of the drill bit therethrough in the open position. The deployment valve may be closed when the drill string is pulled within the casing as may be necessary to service the drill string after drilling into a reservoir having a reservoir pressure. To allow the drill string to be removed from the casing, the pressure produced by the formation can be bled off and the drill string removed for servicing. The drill string can then be reinserted, the pressure in the casing above the deployment valve applied to preferably equalize pressure above and below the valve and the drill string run into the hole for further drilling.

The present invention provides a method and apparatus for handling tubulars and drilling with tubulars such as casing into a formation. In one aspect of the invention, the apparatus comprises a circulating head and a cementing head operatively connectible to a gripping member. The circulating head is used to circulate drilling fluid while drilling with casing, and the cementing head is used to cement the casing string within the formation at a desired depth. The present invention also relates to methods and apparatus for isolating a tensile load from a drilling apparatus rotated by a top drive. In one aspect, the present invention provides a load isolator apparatus having an isolator body operatively connected to the top drive and a torque body at least partially disposed in the isolator body. In operation, the bearing assembly transfers the tensile load from the torque body to the isolator body.

A floating rig or structure for drilling in the floor of an ocean using a rotatable tubular includes a seal housing having a rotatable seal connected above a marine riser fixed to the floor of the ocean. The seal rotating with the rotating tubular allows the riser and seal housing to maintain a predetermined pressure in the system that is desirable in underbalanced drilling, gas-liquid mud systems and pressurized mud handling systems. A flexible conduit or hose is used to compensate for the relative movement of the seal housing and the floating structure since the floating structure moves independent of the seal housing. A method for use of the system is also disclosed.

The present invention is an apparatus for use in drilling operations. It uses an under-reamer having a plurality of elongated arms with cutting elements at the ends of the arms for enlarging a previously drilled borehole drilled by a drill bit. One or more stabilizers in close proximity to the under-reamer provide stability to the under-reamer and the drill bit. The stabilizer could be rotating or non-rotating; and could be positioned between the under-reamer and the drill bit, or above the under reamer or above a directional device on the drillstring. The cutting arms are selectively operable to perform the enlargement. The stabilizer may be provided with members that closely fit the size of the borehole.

A bi-center drill bit includes pilot and reaming blades affixed to a body at azimuthally spaced locations. The blades have PDC cutters attached at selected positions. In one aspect, the pilot blades form a section having length along the bit axis less than about 80 percent of a diameter of the section. In another aspect, selected pilot blades and corresponding reaming blades are formed into single spiral structures. In another aspect, shapes and positions of the blades and inserts are selected so that lateral forces exerted by the reaming and the pilot sections are balanced as a single structure. Lateral forces are preferably balanced to within 10 percent of the total axial force on the bit. In another aspect, the center of mass of the bit is located less than about 2.5 percent of the diameter of the bit from the axis of rotation. In another aspect, jets are disposed in the reaming section oriented so that their axes are within about 30 degrees of normal to the axis of the bit. In another aspect, the reaming blades are shaped to conform to the radially least extensive, from the longitudinal axis, of a pass-through circle or a drill circle, so the cutters on the reaming blades drill at the drill diameter, without contact to the cutters on the reaming blades when the bit passes through an opening having about the pass-through diameter.

An expandable reamer apparatus and methods for reaming a borehole, wherein a laterally movable blade carried by a tubular body may be selectively positioned at an inward position and an expanded position. The laterally movable blade, held inwardly by blade-biasing elements, may be forced outwardly by drilling fluid selectively allowed to communicate therewith by way of an actuation sleeve disposed within the tubular body. Alternatively, a separation element may transmit force or pressure from the drilling fluid to the movable blade. Further, a chamber in communication with the movable blade may be pressurized by way of a downhole turbine or pump. A ridged seal wiper, compensator, movable bearing pad, fixed bearing pad preceding the movable blade, or an adjustable spacer element to alter expanded blade position may be included within the expandable reamer. In addition, a drilling fluid pressure response indicating an operational characteristic of the expandable reamer may be generated.

A Drill-To-The-Limit (DTTL) drilling method variant to Managed Pressure Drilling (MPD) applies constant surface backpressure, whether the mud is circulating (choke valve open) or not (choke valve closed). Because of the constant application of surface backpressure, the DTTL method can use lighter mud weight that still has the cutting carrying ability to keep the borehole clean. The DTTL method identifies the weakest component of the pressure containment system, such as the fracture pressure of the formation or the casing shoe leak off test (LOT). With a higher pressure rated RCD, such as 5,000 psi (34,474 kPa) dynamic or working pressure and 10,000 psi (68,948 kPa) static pressure, the limitation will generally be the fracture pressure of the formation or the LOT. In the DTTL method, since surface backpressure is constantly applied, the pore pressure limitation of the conventional drilling window can be disregarded in developing the fluid and drilling programs. Using the DTTL method a deeper wellbore can be drilled with larger resulting end tubulars, such as casings and production liners, than had been capable with conventional MPD applications.

The present invention provides a method and apparatus for setting concentric casing strings within a wellbore in one run-in of a casing working string. In one aspect of the invention, the apparatus comprises a drilling system comprising concentric casing strings, with each casing string having a drill bit piece disposed at the lower end thereof. The drill bit pieces of adjacent casing strings are releasably connected to one another. In another aspect of the invention, a method is provided for setting concentric casing strings within a wellbore with the drilling system. In another aspect of the invention, the releasably connected drill bit pieces comprise a drill bit assembly.

A method and apparatus for evaluating the resistivity of earth formations surrounding a borehole, particularly high-contrast thin-layer formations or at high dip angles. The method involves positioning a pair of transmitters and a pair of receivers within the borehole, the receivers or transmitters adhering to specific spacing limitations, alternately transmitting electromagnetic energy of a particular frequency and receiving voltage data associated with the transmitted energy. Multiple voltage data are acquired and a representation of a resistivity or conductivity profile is created from a formulated difference of the data from a particular depth and/or neighboring depths. The apparatus forms part of a well logging system including a well tool adapted to be moveable through a borehole. The apparatus being coupled to the well tool and adapted with means to input voltage data developed by the receivers disposed on the well tool. The apparatus further adapted with means for performing calculations to determine a conductivity profile and for recording the profile on an output record medium.

The present invention relates to subterranean well stimulation. More particularly, the present invention relates to improved methods of stimulating subterranean formations during drilling operations. In some embodiments, the present invention discloses methods of stimulating a section of a subterranean formation comprising (a) forming at least a portion of a well bore that at least penetrates a section of the subterranean formation using a drilling operation; (b) stimulation a section of the subterranean; and (c) continuing the drilling operation. In other embodiments, the present invention discloses methods of stimulation a section of a subterranean formation comprising (a) forming at least a portion of a well bore that at least penetrates a section of the subterranean formation using a drilling operation; (b) stimulating a section of the subterranean formation; and (c) continuing the drilling operation.

Methods of consolidating formations include drilling a well bore with a drilling fluid that comprises water, a polymeric cationic catalyst which is adsorbed on minerals and rocks in weak unconsolidated zones or formations and then further contacting the unconsolidated formation with a treating fluid comprising a water soluble or dispersible polymer which is cross-linked by a thermoset resin and causes the resin to be hard and tough when cured, and a water soluble or dispersible thermoset resin which cross-links the polymer, is catalyzed and cured by the catalyst and consolidates the weak zone or formation so that sloughing is prevented.

A system is for controlling borehole operations using a computational drilling process model representing the combined effect of downhole conditions and the operation of a drillstring. The drilling process model is continually updated with downhole measurements made during a drilling operation. From the updated drilling process model, a set of optimum drilling parameters is determined and communicated to a surface equipment control system. Further, the system allows the surface equipment control system to automatically adjust current surface equipment control settings based on the updated optimum drilling parameters. Various control scripts are generated and executed to inform the surface equipment control system based on a present drilling mode.