8774 results about "Drilling fluid" patented technology

In one embodiment, a method for drilling a wellbore includes an act of drilling the wellbore by injecting drilling fluid through a tubular string disposed in the wellbore, the tubular string comprising a drill bit disposed on a bottom thereof. The drilling fluid exits the drill bit and carries cuttings from the drill bit. The drilling fluid and cuttings (returns) flow to a surface of the wellbore via an annulus defined by an outer surface of the tubular string and an inner surface of the wellbore. The method further includes an act performed while drilling the wellbore of measuring a first annulus pressure (FAP) using a pressure sensor attached to a casing string hung from a wellhead of the wellbore. The method further includes an act performed while drilling the wellbore of controlling a second annulus pressure (SAP) exerted on a formation exposed to the annulus.

A system and method for controlling formation pressures during drilling of a subterranean formation utilizing a selectively fluid backpressure system in which fluid is pumped down the drilling fluid return system in response to detected borehole pressures. A pressure monitoring system is further provided to monitor detected borehole pressures, model expected borehole pressures for further drilling and control the fluid backpressure system.

A method of the preparation and utilization of polymerized alpha-hydroxycarboxylic-acid-coated proppants for gravel pack and removal of filter cake that was deposited by reservoir drilling fluid. In a preferred example, polyglycolic-acid-coated sand is used to replace conventional gravel pack sand typically used for gravel packing. Under downhole conditions, the acidic by-product generated from the hydration of polyglycolic-acid-coated sand can break down acid-soluble and/or acid-breakable components embedded in the filter cake. This reaction enhances the filter cake removal and the flow of hydrocarbon from the producing formation. The polyglycolic-acid-coated sand may be produced by polymerizing a glycolic acid with a natural or synthetic proppant like 20-40 mesh commercial sand, at temperatures of about 210° F. or higher.

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.

An apparatus for use downhole is disclosed that, in one configuration includes a downhole tool configured to operate in an active position and an inactive position and an actuation device, which may include a control unit. The apparatus includes a telemetry unit that sends a first pattern recognition signal to the control unit to move the tool into the active position and a second pattern recognition signal to move the tool into the inactive position. The apparatus may be used for drilling a subterranean formation and include a tubular body and one or more extendable features, each positionally coupled to a track of the tubular body, and a drilling fluid flow path extending through a bore of the tubular body for conducting drilling fluid therethrough. A push sleeve is disposed within the tubular body and coupled to the one or more features. A valve assembly is disposed within the tubular body and configured to control the flow of the drilling fluid into an annular chamber in communication with the push sleeve; the valve assembly comprising a mechanically operated valve and/or an electronically operated valve. Other embodiments, including methods of operation, are provided.

Embodiments of systems, program product, and methods for controlling drilling fluid pressures are provided. These embodiments, for example, can provide dynamic density control with highly adaptive, real-time, process-control and are scalable to any rig, large or small, on land or water. Combined static and dynamic stresses and displacements can be determined continuously at strategic locations in and around the wellbore of a well so that insitu and operational induced pressure window limitations at specific weak-points or other locations of interest are controlled.

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.

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 trigger device for setting a downhole tool is disclosed. The trigger device includes a retaining member that prevents the downhole tool from setting until it is properly positioned within the well. Regardless of the type of downhole tool or the type of trigger device, the retaining member includes a dissolvable material that dissolves when contacted by a solvent. The dissolvable material is preferably one that dissolves at a known rate so that the amount of time necessary for the downhole tool to set is pre-determined. Preferably, the solvent is a water-based or hydrocarbon-based drilling fluid or mud.

A corrosion control system is disclosed including an anionic oxygen inhibitor, a cationic acid inhibitor or dispersant, and a noxious species inhibitor or scavenger for use in a fluid in contact with a metallic surface at low temperature, moderate temperature and especially at high temperature. A drilling fluid, a completion fluid, a production fluid and a geothermal fluid including an effective amount of the corrosion control system is also disclosed as well as methods for making and using same.

In one embodiment, a method for drilling a wellbore includes injecting drilling fluid into a top of a tubular string disposed in the wellbore at a first flow rate. The tubular string includes: a drill bit disposed on a bottom thereof, tubular joints connected together, a longitudinal bore therethrough, and a port through a wall thereof. The drilling fluid exits the drill bit and carries cuttings from the drill bit. The cuttings and drilling fluid (returns) flow to the surface via an annulus defined between the tubular string and the wellbore. The method further includes rotating the drill bit while injecting the drilling fluid; remotely removing a plug from the port, thereby opening the port; and injecting drilling fluid into the port at a second flow rate while adding a tubular joint or stand of joints to the tubular string. The injection of drilling fluid into the tubular string is continuously maintained between drilling and adding the joint or stand to the drill string. The method further includes remotely installing a plug into the port, thereby closing the port. The first and second flow rates may be substantially equal or different.

An expandable reamer apparatus for drilling a subterranean formation includes a tubular body, one or more blades, each blade positionally coupled to a sloped track of the tubular body, a push sleeve and a drilling fluid flow path extending through an inner bore of the tubular body for conducting drilling fluid therethrough. Each of the one or more blades includes at least one cutting element configured to remove material from a subterranean formation during reaming. The push sleeve is disposed in the inner bore of the tubular body and coupled to each of the one or more blades so as effect axial movement thereof along the track to an extended position responsive to exposure to a force or pressure of drilling fluid in the flow path of the inner bore. Other embodiments of the expandable reamer apparatus are provided.

A method for drilling a borehole includes; providing a drill string of drill pipe including a center bore, a distal end, a bit assembly at the distal end; hanging a liner from the drill string, thereby forming an annular space between the drill string and the liner and with the bit assembly extending from a lower end of the liner; positioning the drill string with the liner attached thereto in a borehole such that a second annular space is formed between the liner and the borehole wall; operating the bit assembly to proceed with drilling the borehole; and circulating drilling fluid down through the center bore of the drill string out through the bit assembly and down through the second annular space between the liner and the borehole wall, the drilling fluid returning up through the annular space between the drill string and the liner.

An expandable reamer apparatus for drilling a subterranean formation may include a tubular body, one or more blades, each blade positionally coupled to a sloped track of the tubular body, a push sleeve and a drilling fluid flow path extending through an inner bore of the tubular body for conducting drilling fluid therethrough. Each of the one or more blades may be configured to ream a subterranean formation. The push sleeve may be disposed in the inner bore of the tubular body and coupled to each of the one or more blades so as effect axial movement thereof along the track to an extended position responsive to exposure to a force or pressure of drilling fluid in the flow path of the inner bore. Each blade may include one or more roller elements for reaming a wellbore.

A rotary drill bit for drilling subterranean formations configured with at least one protective structure proximate to the rotationally leading and trailing edges of a gage trimmer, wherein the at least one protective structure is positioned at substantially the same exposure as its associated gage trimmer. Particularly, the apparatus of the present invention may provide protection for gage trimmers during drilling, tripping, and/or rotation within a casing; i.e., when changing a drilling fluid. Protective structures may be configured and located according to anticipated drilling conditions including helix angles. In addition, a protective structure may be proximate to more than one gage trimmer while having a substantially equal exposure to each associated gage trimmer. Methods of use and a method of rotary bit design are also disclosed.

The present invention generally provides apparatus and methods for reducing the pressure of a circulating fluid in a wellbore. In one aspect of the invention an ECD (equivalent circulation density) reduction tool provides a means for drilling extended reach deep (ERD) wells with heavyweight drilling fluids by minimizing the effect of friction head on bottomhole pressure so that circulating density of the fluid is close to its actual density. With an ECD reduction tool located in the upper section of the well, the friction head is substantially reduced, which substantially reduces chances of fracturing a formation.

A downhole tool assembly is configured for repeated and selective hydraulic actuation and deactuation. A piston assembly is configured to reciprocate axially in a downhole tool body. The piston assembly reciprocates between a first axial position and second and third axial positions that axially oppose the first position. The downhole tool is actuated when the piston assembly is in the third axial position and deactuated when the piston assembly is in either of the first or second axial positions. A spring member biases the piston assembly towards the first axial position while drilling fluid pressure in the tool body urges the piston assembly towards the second and third axial positions. Downhole tool actuation and deactuation may be controlled from the surface, for example, via cycling the drilling fluid flow rate.