|Publication number||US7136795 B2|
|Application number||US 10/604,208|
|Publication date||Nov 14, 2006|
|Filing date||Jul 1, 2003|
|Priority date||Nov 10, 1999|
|Also published as||US20050006145|
|Publication number||10604208, 604208, US 7136795 B2, US 7136795B2, US-B2-7136795, US7136795 B2, US7136795B2|
|Original Assignee||Schlumberger Technology Corporation|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (103), Referenced by (9), Classifications (20), Legal Events (2) |
|External Links: USPTO, USPTO Assignment, Espacenet|
Control method for use with a steerable drilling system
US 7136795 B2
A control method for use with a steerable drilling system comprises the steps of inputting parametric model data representative of drilling conditions and using the data to determine achievable drilling directions.
1. A method of predicting the operation of a steerable drilling system comprising the steps of:
calculating an ideal reachability ellipse using the equations:
inputting data representative of actual drilling conditions into a parametric model;
calculating predicted build and turn gain, cross-coupling and bias values to derive build and turn responsiveness values attainable under given operating conditions from the parametric model to produce a predicted reachability ellipse;
plotting the predicted reachability ellipse and ideal reachability ellipse on a diagram to compare the predicted build and turn responsiveness to the ideal response for one or more sets of operating conditions.
2. A method as claimed in claim 1, wherein the model data includes data representative of at least one of: weight on bit, rotational speed, rate of progress, torque, pressure, inclination, dip and azimuth of bedding planes or other formation characteristics, hole curvature/gauge or other geometric conditions, bit type and condition, and errors in instrumentation readings.
3. A method as claimed in claim 1, wherein an output signal is produced which is used to control a display on which the predicted reachability ellipse diagram is displayed to provide an operator with information for use in controlling the operation of the drilling system.
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation in part of U.S. patent application Ser. No. 09/869,686 filed Oct. 9, 2001 now U.S. Pat. No. 6,601,658 which was filed as PCT application No. PCT/GB00/04291 filed Nov. 10, 2000, which claims priority from U.S. Provisional application No. 60/164,681 filed on Nov. 10, 1999.
BACKGROUND OF INVENTION
This invention relates to a method for use in controlling the operation of a steerable drilling system. The method is particularly suitable for use with a rotary steerable system, but may be used in other types of steerable drilling system used in the formation of subterranean wells. In particular, the invention relates to a method of predicting how a drilling system will operate, respond or react to various operating conditions and changes therein.
One type of rotary steerable system comprises a downhole assembly including a drill bit. The drill bit is carried by a drill string which is rotated typically by a well head located drive arrangement. A bias unit is included in the downhole assembly, the bias unit including a plurality of hinged pads moveable between extended and retracted positions. The pads are moved hydraulically using drilling fluid under the control of a valve arrangement. The valve arrangement is designed to permit control over the pads such that, when desired, the pads can be moved to their extended positions in turn as the bias unit rotates. By appropriate control over the pads, the bias unit can be operated to apply a sideways load on the drill bit which in turn will cause the formation of a curve in the well bore being drilled. The orientation of the curve will depend upon how the bias unit is controlled.
It has been found that a number of factors must be taken into account when controlling the operation of a rotary steerable system. For example, the rate of change of direction of the bore hole being formed in response to the application of a given command signal to the bias unit depends upon several factors associated with the drilling system, for example rotary speed, weight on bit, rate of penetration and several factors associated with the formation being drilled, for example the dip and azimuth of bedding planes. As a consequence, it is common for well bores drilled using steerable drilling systems to deviate from their desired paths. Such well bores may be of tortuous form containing many dog legs. Depending upon the orientation of the curves formed in the well bore, water or gas may tend to collect in the curves. Such accumulation of water or gas may impair subsequent use of the well bore in the extraction of oil.
SUMMARY OF INVENTION
It is an object of the invention to provide a control method for use with a steerable drilling system, the method simplifying control of the drilling system.
According to the invention there is provided a method of predicting the operation of a steerable drilling system comprising the steps of inputting parametric model data representative of drilling conditions, calculating build and turn gain, cross-coupling and bias values to derive build and turn responsiveness values, using the derived build and turn responsiveness values in controlling the operation of a steerable drilling system, measuring the actual build and turn responsiveness of the system, and calculating a reachability ellipse diagram which compares the actual build and turn responsiveness to the ideal response to predict achievable rates of penetration and build and turn responsiveness for one or more sets of later operating conditions.
The parametric model data used is conveniently derived using data collected, in real time, during drilling. The parametric model data may include data representative of one or more of the following parameters: weight on bit, rotational speed, rate of penetration, torque, pressure, inclination, dip and azimuth of bedding planes or other formation characteristics, hole curvature/gauge or other geometric conditions, bit type and condition, and errors in instrumentation readings.
The use of such a system is advantageous in that compensation can be made for the operating conditions, thus the risk of supplying the drilling system with instructions to drill a curve of too tight or too small a radius of curvature or of too great or small a length in a given direction can be reduced, thus permitting the drilling of a well bore of less tortuous form.
The ellipse diagram may be displayed in a graphic form, for example in the form of a graph of build rate response against turn rate response upon which is plotted an envelope indicating the achievable responses for one or more sets of operating conditions.
With such a display, an operator will be able to see whether it is possible to steer the drill bit of the drilling system in a given direction under one or more sets of operating conditions. The operator may then be able to modify one or more of the operating conditions over which he has some control to ensure that the operating conditions under which the drilling system is operating are such as to permit steering of the drill bit in the desired direction.
BRIEF DESCRIPTION OF DRAWINGS
The invention will further be described, by way of example, with reference to the accompanying drawings.
FIG. 1 is a diagram illustrating a drilling installation, with which the method of the invention may be used.
FIG. 2 is a sectional view illustrating part of the downhole assembly of the installation of FIG. 1.
FIG. 3 is a flowchart illustrating a method in accordance with an embodiment of the invention.
FIG. 4 is a representation of an output achieved using the method described with reference to FIG. 3.
FIG. 5 is a block diagram illustrating the use of the method in conjunction with a drilling system of the type shown in FIG. 1.
FIG. 6 is a reachability diagram produced using the method of the invention.
FIG. 1 shows diagrammatically a typical rotary drilling installation of a kind in which the methods according to the present invention may be employed.
In the following description the terms “clockwise” and anti-clockwise” refer to the direction of rotation as viewed looking downhole.
As is well known, the bottom hole assembly includes a drill bit 1, and is connected to the lower end of a drill string 2 which is rotatably driven from the surface by a rotary table 3 on a drilling platform 4. The rotary table is driven by a drive motor indicated diagrammatically at 5 and raising and lowering of the drill string, and application of weight-on-bit, is under the control of draw works indicated diagrammatically at 6.
The bottom hole assembly includes a modulated bias unit 10 to which the drill bit 1 is connected and a roll stabilised control unit 9 which controls operation of the bias unit 10 in accordance with signals transmitted to the control unit from the surface. The bias unit 10 may be controlled to apply a lateral bias to the drill bitin a desired direction so as to control the direction of drilling.
Referring to FIG. 2, the bias unit 10 comprises an elongate main body structure provided at its upper end with a threaded pin 11 for connecting the unit to a drill collar, incorporating the roll stabilised control unit 9, which is in turn connected to the lower end of the drill string. The lower end 12 of the body structure is formed with a socket to receive the threaded pin of the drill bit.
There are provided around the periphery of the bias unit, towards its lower end, three equally spaced hydraulic actuators 13. Each hydraulic actuator 13 is supplied with drilling fluid under pressure through a respective passage 14 under the control of a rotatable disc valve 15 located in a cavity 16 in the body structure of the bias unit. Drilling fluid delivered under pressure downwardly through the interior of the drill string, in the normal manner, passes into a central passage 17 in the upper part of the bias unit, through a filter, and through an inlet 19 to be delivered at an appropriate pressure to the cavity 16.
The disc valve 15 is controlled by an axial shaft 21 which is connected by a coupling 22 to the output shaft of the control unit, which can be roll stabilised.
The control unit, when roll stabilised (i.e. non-rotating in space) maintains the shaft 21 substantially stationary at a rotational orientation which is selected according to the direction in which the drill bit is to be steered. As the bias unit rotates around the stationary shaft 21 the disc valve 15 operates to deliver drilling fluid under pressure to the three hydraulic actuators 13 in succession. The hydraulic actuators are thus operated in succession as the bias unit rotates, each in the same rotational position so as to displace the bias unit laterally in a selected direction. The selected rotational position of the shaft 21 in space thus determines the direction in which the bias unit is actually displaced and hence the direction in which the drill bit is steered.
If the shaft 21 is not held in a substantially stationary position, then the actuators 13 are operated in turn but are not all operated in the same rotational position. As a result, rather than urging the bias unit laterally in a given direction, the direction in which the bias unit is urged changes continuously with the result that there is no net bias applied by the bias unit.
Drilling systems of the general type described hereinbefore are described in greater detail in EP 0520733, EP 0677640, EP 0530045, EP 0728908 and EP 0728909, the content of which is incorporated herein by reference.
As described hereinbefore, for a given biasing load applied by the bias unit, the rate of change of direction of the bore being formed is influenced by a number of factors. The factors influencing the vertical rate of change, the build rate, are not always the same as those influencing the rate of change in the horizontal direction, known as the turn rate.
FIG. 3 is a flowchart illustrating a method of controlling the operating of the drilling system of FIGS. 1 and 2. As shown in FIG. 3, at the start of drilling a control system used in controlling the position occupied by the shaft 21 is initialised with data representative of the likely drilling conditions. The input data is representative of factors associated with the drilling system, the formation being drilled, the direction of the well bore, and the shape of the well bore. The factors associated with the drilling system include the intended weight on bit, rate of penetration, rotational speed, torque, pressure and inclination of the drill bit. The factors associated with the formation being drilled include the dip and azimuth of bedding planes. Data representative of likely errors in sensor readings and representative of the type and condition of the drill bit may also be input. If no suitable data is available to be input, then a default data set may be used.
Whilst drilling is taking place, data representative of the actual drilling conditions is collected and transmitted to the control system. The readings are conveniently taken at intervals, for example at every 30 metres of measured depth. The measured data is used to update the data of the parametric model. FIG. 5 is a block diagram illustrating the interrelationship between the various parts of the drilling system and the method of operation thereof.
The updated data set of the parametric model is used to calculate a range of achievable or reachable drilling directions which it is predicted can be attained under chosen drilling conditions, and this information is displayed graphically to the operator of the drilling system, for example in the form of a chart as shown in FIG. 4. As shown in FIG. 4, the chart takes the form of a graph of build rate against turn rate upon which is plotted an envelope 25 illustrating the predicted achievable drilling direction for the prevailing drilling conditions, or default conditions in the event that default data values are being used. Also plotted on the graph is the current drilling direction 26. The chart may also indicate a desired drilling direction 27 if this information has been input by the operator. Such a desired drilling direction 27 is indicated on FIG. 4.
Using the information displayed, the operator can determine whether or not it is possible to achieve the desired drilling direction 27 under the prevailing drilling conditions. This is a relatively simple task as, if the desired drilling direction 27 falls within the envelope 25 then it is achievable with the current drilling conditions, and drilling can continue with appropriate signals sent to the bias unit to urge the drill bit to drill in the desired direction.
If the desired drilling direction 27 falls outside of the envelope 25 of achievable directions (as shown in FIG. 4), then obviously if the well bore is to be drilled in the desired direction, this can only be achieved if the drilling conditions change. Although the operator has no control over a number of the drilling conditions, in particular the drilling conditions governed by the formation, he does have control over some of the drilling conditions associated with the operation of the drill bit. For example, the operator could modify the rate of penetration, weight-on-bit, or rotational speed of the drill bit. Prior to modifying the drilling conditions, the operator may input trial values of certain of the operating parameters into the control system. The control system is arranged to display the envelope 28 of achievable drilling directions for those operating conditions. If the trial values for the operating conditions result in the production of an envelope of achievable drilling directions including the desired drilling direction 27, then the operator may choose to use those drilling parameter values in the control of the drilling system and then to direct the drill bit in the desired direction. Alternatively, the control system may be set up in such a manner as to output suitable values for the drilling parameters in response to the operator entering a desired drilling direction.
FIG. 6 illustrates an alternative form of reachability diagram. In this form of reachability diagram, an ideal response is illustrated, this response being denoted by numeral 30. The ideal response is shown as being circular, suggesting that the response of the drilling system to a change in drilling conditions is entirely symmetrical. The diagram further includes a predicted achievable response denoted by numeral 32, this response being equivalent, in many respects, to the envelope 25 plotted on the graph of FIG. 3, and showing the range of drilling directions which it is predicted can be attained under given operating conditions. As shown, the predicted achievable response 32 takes the form of a distorted, shifted and rotated ellipse which is derived by modifying the ideal response using the calculated gain and bias responsiveness values (see below) of the system. Both the ideal response 30 and the predicted achievable response 32 are provided with notches 34 of varying sizes provided to assist an operator in comparing the predicted achievable response with the ideal response which would be achieved under ideal drilling conditions. The operator can use the reachability diagram to determine the size of doglegs or the like which can be formed, and to determine when a dogleg in a given direction is not attainable under given operating conditions.
A number of different algorithms may be used in the calculation of the envelope of achievable drilling directions.
In one simple technique, the response of the system to a given input is used to calculate gain values KB and KT, cross-coupling values CBT and CTB and bias values Bbias and Tbias (where B and T represent Build and Turn respectively).
The build and turn responsiveness values are then calculated by, for each factor influencing the responsiveness of the system to a steering command, calculating a normalised deviation of the parameter value from the mean value of that parameter and multiplying the deviation by a coefficient representative of the responsiveness of the system to that one of the factors, and adding the results for each factor to one another and to the relevant ones of the gain, cross-coupling and bias values. These calculations can be expressed by the following equations:
As mentioned above, other mathematical techniques may be used in the derivation of the envelopes of achievable steering directions.
Rather than use the method to determine which steering directions are achievable for a given set of drilling conditions, or to determine sets of drilling conditions which can be used to achieve steering in a chosen direction, the method may be used to determine achievable rates of penetration for a given set of drilling conditions. Such use of the method may have the advantage that the rate of penetration can be optimised.
Although the description hereinbefore related to the use of a specific type of steerable system, it will be appreciated that the invention is not restricted to the use of the method with the described drilling system and that the invention could be used with a range of other drilling systems.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US712887||May 9, 1900||Nov 4, 1902||Josef Wyczynski||Centering and guiding device for deep-boring apparatus with eccentric boring-tool.|
|US1971480||Jun 25, 1931||Aug 28, 1934||J S Abercrombie Company||Means and method of straightening well bores|
|US2319236||Aug 22, 1940||May 18, 1943||Sperry Sun Well Surveying Co||Deflecting tool|
|US2345766||Dec 2, 1940||Apr 4, 1944||Eastman Oil Well Survey Co||Deflecting tool|
|US2585207||Oct 11, 1950||Feb 12, 1952||Zublin John A||Apparatus for drilling lateral bores deviating from vertical well bores|
|US2687282||Jan 21, 1952||Aug 24, 1954||Eastman Oil Well Survey Co||Reaming bit structure for earth bores|
|US2694549||Jan 21, 1952||Nov 16, 1954||Eastman Oil Well Survey Co||Joint structure between flexible shafting and drill bit structure for drilling lateral bores|
|US2712434||Nov 23, 1953||Jul 5, 1955||Giles Melvin L||Directional drilling tool|
|US2857141||Apr 25, 1957||Oct 21, 1958||Carpenter Frank H||Well tool|
|US2876992||Nov 4, 1954||Mar 10, 1959||Eastman Oil Well Survey Co||Deflecting tools|
|US3051255||May 18, 1960||Aug 28, 1962||Deely Carroll L||Reamer|
|US3062303||Mar 21, 1960||Nov 6, 1962||Shell Oil Co||Method and apparatus for controlling hole direction and inclination|
|US3068946||Dec 15, 1958||Dec 18, 1962||Eastman Oil Well Survey Co||Knuckle joint|
|US3092188||Jul 31, 1961||Jun 4, 1963||Whipstock Inc||Directional drilling tool|
|US3098534||Jun 14, 1960||Jul 23, 1963||Denver Wood Merlin||Directional drill with hydraulically extended shoe|
|US3104728||Jul 25, 1961||Sep 24, 1963|| ||hadley|
|US3123162||Aug 4, 1961||Mar 3, 1964|| ||Xsill string stabilizer|
|US3129776||Mar 16, 1960||Apr 21, 1964||Mann William L||Full bore deflection drilling apparatus|
|US3225843||Sep 14, 1961||Dec 28, 1965||Exxon Production Research Co||Bit loading apparatus|
|US3305771||Aug 30, 1963||Feb 21, 1967||Arps Corp||Inductive resistivity guard logging apparatus including toroidal coils mounted on a conductive stem|
|US3309656||Jun 10, 1964||Mar 14, 1967||Mobil Oil Corp||Logging-while-drilling system|
|US3370657||Oct 24, 1965||Feb 27, 1968||Trudril Inc||Stabilizer and deflecting tool|
|US3457999||Aug 31, 1967||Jul 29, 1969||Intern Systems & Controls Corp||Fluid actuated directional drilling sub|
|US3512592||Mar 14, 1968||May 19, 1970||Exxon Production Research Co||Offshore drilling method and apparatus|
|US3561549||Jun 7, 1968||Feb 9, 1971||Smith Ind International Inc||Slant drilling tools for oil wells|
|US3575247||Jul 7, 1969||Apr 20, 1971||Shell Oil Co||Diamond bit unit|
|US3637032||Jan 22, 1970||Jan 25, 1972||Jeter John D||Directional drilling apparatus|
|US3667556||Jan 5, 1970||Jun 6, 1972||Henderson John Keller||Directional drilling apparatus|
|US3743034||May 3, 1971||Jul 3, 1973||Shell Oil Co||Steerable drill string|
|US3799279||Sep 25, 1972||Mar 26, 1974||Farris R||Optionally stabilized drilling tool|
|US3878903||Dec 4, 1973||Apr 22, 1975||Cherrington Martin Dee||Apparatus and process for drilling underground arcuate paths|
|US3888319||Nov 26, 1973||Jun 10, 1975||Continental Oil Co||Control system for a drilling apparatus|
|US3903974||Mar 12, 1974||Sep 9, 1975||Cullen Roy H||Drilling assembly, deviation sub therewith, and method of using same|
|US3974886||Feb 27, 1975||Aug 17, 1976||Blake Jr Jack L||Directional drilling tool|
|US3997008||Jun 9, 1975||Dec 14, 1976||Smith International, Inc.||Drill director|
|US4022287||Apr 20, 1976||May 10, 1977||Sandvik Aktiebolag||Percussion drill bit|
|US4027301||Apr 21, 1975||May 31, 1977||Sun Oil Company Of Pennsylvania||System for serially transmitting parallel digital data|
|US4040494||Sep 15, 1975||Aug 9, 1977||Smith International, Inc.||Drill director|
|US4040495||Dec 22, 1975||Aug 9, 1977||Smith International, Inc.||Drilling apparatus|
|US4076084||Jul 16, 1973||Feb 28, 1978||Amoco Production Company||Oriented drilling tool|
|US4080115||Sep 27, 1976||Mar 21, 1978||A-Z International Tool Company||Progressive cavity drive train|
|US4152545||Apr 5, 1965||May 1, 1979||Martin Marietta Corporation||Pulse position modulation secret communication system|
|US4184553||Oct 25, 1978||Jan 22, 1980||Conoco, Inc.||Method for controlling direction of horizontal borehole|
|US4185704||May 3, 1978||Jan 29, 1980||Maurer Engineering Inc.||Directional drilling apparatus|
|US4190123||Jul 14, 1978||Feb 26, 1980||John Roddy||Rock drill bit loading device|
|US4211292||Jul 27, 1978||Jul 8, 1980||Evans Robert F||Borehole angle control by gage corner removal effects|
|US4220213||Dec 7, 1978||Sep 2, 1980||Hamilton Jack E||Method and apparatus for self orienting a drill string while drilling a well bore|
|US4241796||Nov 15, 1979||Dec 30, 1980||Terra Tek, Inc.||Active drill stabilizer assembly|
|US4263552 *||Dec 8, 1978||Apr 21, 1981||Weber Harold J||Translative intelligencer apparatus providing polyindicative response|
|US4270619||Oct 3, 1979||Jun 2, 1981||Base Jimmy D||Downhole stabilizing tool with actuator assembly and method for using same|
|US4291773||Dec 10, 1979||Sep 29, 1981||Evans Robert F||Strictive material deflectable collar for use in borehole angle control|
|US4305474||Feb 4, 1980||Dec 15, 1981||Conoco Inc.||Thrust actuated drill guidance device|
|US4351037||Jan 10, 1980||Sep 21, 1982||Scherbatskoy Serge Alexander||Systems, apparatus and methods for measuring while drilling|
|US4357634||Dec 26, 1979||Nov 2, 1982||Chung David H||Encoding and decoding digital information utilizing time intervals between pulses|
|US4388974||Apr 13, 1981||Jun 21, 1983||Conoco Inc.||Variable diameter drill rod stabilizer|
|US4394881||Jun 12, 1980||Jul 26, 1983||Shirley Kirk R||Drill steering apparatus|
|US4407377||Apr 16, 1982||Oct 4, 1983||Russell Larry R||Surface controlled blade stabilizer|
|US4416339||Jan 21, 1982||Nov 22, 1983||Baker Royce E||Bit guidance device and method|
|US4428441||Jan 8, 1981||Jan 31, 1984||Mobil Oil Corporation||Method of drilling a deviated wellbore|
|US4449595||May 17, 1982||May 22, 1984||Holbert Don R||Method and apparatus for drilling a curved bore|
|US4456080||Sep 8, 1982||Jun 26, 1984||Holbert Don R||Stabilizer method and apparatus for earth-boring operations|
|US4461359||Apr 23, 1982||Jul 24, 1984||Conoco Inc.||Rotary drill indexing system|
|US4465147||Jan 31, 1983||Aug 14, 1984||Shell Oil Company||Method and means for controlling the course of a bore hole|
|US4491187||Jun 29, 1983||Jan 1, 1985||Russell Larry R||Surface controlled auxiliary blade stabilizer|
|US4492276||Oct 13, 1983||Jan 8, 1985||Shell Oil Company||Down-hole drilling motor and method for directional drilling of boreholes|
|US4515225||Jan 29, 1982||May 7, 1985||Smith International, Inc.||Mud energized electrical generating method and means|
|US4523652||Jul 1, 1983||Jun 18, 1985||Atlantic Richfield Company||Drainhole drilling assembly and method|
|US4560013||Feb 16, 1984||Dec 24, 1985||Baker Oil Tools, Inc.||Apparatus for directional drilling and the like of subterranean wells|
|US4572305||Feb 27, 1984||Feb 25, 1986||George Swietlik||Drilling apparatus|
|US4577701||Aug 8, 1984||Mar 25, 1986||Mobil Oil Corporation||System of drilling deviated wellbores|
|US4635736||Nov 22, 1985||Jan 13, 1987||Shirley Kirk R||Drill steering apparatus|
|US4637479||May 31, 1985||Jan 20, 1987||Schlumberger Technology Corporation||Methods and apparatus for controlled directional drilling of boreholes|
|US4638873||May 23, 1984||Jan 27, 1987||Welborn Austin E||Direction and angle maintenance tool and method for adjusting and maintaining the angle of deviation of a directionally drilled borehole|
|US4655289||Oct 4, 1985||Apr 7, 1987||Petro-Design, Inc.||Remote control selector valve|
|US4662458||Oct 23, 1985||May 5, 1987||Nl Industries, Inc.||Method and apparatus for bottom hole measurement|
|US4667751||Oct 11, 1985||May 26, 1987||Smith International, Inc.||System and method for controlled directional drilling|
|US4683956||Oct 15, 1984||Aug 4, 1987||Russell Larry R||Method and apparatus for operating multiple tools in a well|
|US4690229||Jan 22, 1986||Sep 1, 1987||Raney Richard C||Radially stabilized drill bit|
|US4697651||Dec 22, 1986||Oct 6, 1987||Mobil Oil Corporation||Method of drilling deviated wellbores|
|US4699224||May 12, 1986||Oct 13, 1987||Sidewinder Joint Venture||Method and apparatus for lateral drilling in oil and gas wells|
|US4714118||May 22, 1986||Dec 22, 1987||Flowmole Corporation||Technique for steering and monitoring the orientation of a powered underground boring device|
|US4732223||Jun 12, 1985||Mar 22, 1988||Universal Downhole Controls, Ltd.||Controllable downhole directional drilling tool|
|US4739843||Jul 2, 1987||Apr 26, 1988||Sidewinder Tool Joint Venture||Apparatus for lateral drilling in oil and gas wells|
|US4763258||Feb 26, 1986||Aug 9, 1988||Eastman Christensen Company||Method and apparatus for trelemetry while drilling by changing drill string rotation angle or speed|
|US4787093||Sep 15, 1986||Nov 22, 1988||Develco, Inc.||Combinatorial coded telemetry|
|US4794534 *||Aug 8, 1985||Dec 27, 1988||Amoco Corporation||Method of drilling a well utilizing predictive simulation with real time data|
|US4804051 *||Sep 25, 1987||Feb 14, 1989||Nl Industries, Inc.||Method of predicting and controlling the drilling trajectory in directional wells|
|US4807708||Nov 28, 1986||Feb 28, 1989||Drilex Uk Limited And Eastman Christensen Company||Directional drilling of a drill string|
|US4811798||Oct 30, 1986||Mar 14, 1989||Team Construction And Fabrication, Inc.||Drilling motor deviation tool|
|US4821815||May 22, 1986||Apr 18, 1989||Flowmole Corporation||Technique for providing an underground tunnel utilizing a powered boring device|
|US4821817||Jan 3, 1986||Apr 18, 1989||Smf International||Actuator for an appliance associated with a ducted body, especially a drill rod|
|US4836301||May 15, 1987||Jun 6, 1989||Shell Oil Company||Method and apparatus for directional drilling|
|US4842083||Jul 23, 1987||Jun 27, 1989||Raney Richard C||Drill bit stabilizer|
|US4844178||Mar 25, 1988||Jul 4, 1989||Smf International||Drilling device having a controlled path|
|US4848488||Mar 25, 1988||Jul 18, 1989||Smf International||Method and device for adjusting the path of a drilling tool fixed to the end of a set of rods|
|US4848490||Jun 15, 1987||Jul 18, 1989||Anderson Charles A||Downhole stabilizers|
|US4854397||Sep 15, 1988||Aug 8, 1989||Amoco Corporation||System for directional drilling and related method of use|
|US4854403||Apr 8, 1988||Aug 8, 1989||Eastman Christensen Company||Stabilizer for deep well drilling tools|
|US4858705||Apr 1, 1988||Aug 22, 1989||Institut Francais Du Petrole||Assembly for making oriented bore-holes|
|US4867255||May 20, 1988||Sep 19, 1989||Flowmole Corporation||Technique for steering a downhole hammer|
|US4880067||Feb 17, 1988||Nov 14, 1989||Baroid Technology, Inc.||Apparatus for drilling a curved borehole|
|US4886130||Jul 26, 1988||Dec 12, 1989||Evans Robert F||Nutational technique for limiting well bore deviation|
|US6736221 *||Dec 21, 2001||May 18, 2004||Schlumberger Technology Corporation||Method for estimating a position of a wellbore|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US8210283 *||Dec 22, 2011||Jul 3, 2012||Hunt Energy Enterprises, L.L.C.||System and method for surface steerable drilling|
|US8528219||Aug 17, 2010||Sep 10, 2013||Magnum Drilling Services, Inc.||Inclination measurement devices and methods of use|
|US8596385||Jun 22, 2012||Dec 3, 2013||Hunt Advanced Drilling Technologies, L.L.C.||System and method for determining incremental progression between survey points while drilling|
|US8794353||Jun 28, 2012||Aug 5, 2014||Hunt Advanced Drilling Technologies, L.L.C.||System and method for surface steerable drilling|
|US8818729||Feb 21, 2014||Aug 26, 2014||Hunt Advanced Drilling Technologies, LLC||System and method for formation detection and evaluation|
|US8844649||Dec 31, 2013||Sep 30, 2014||Hunt Advanced Drilling Technologies, L.L.C.||System and method for steering in a downhole environment using vibration modulation|
|US8881414||Sep 9, 2013||Nov 11, 2014||Magnum Drilling Services, Inc.||Inclination measurement devices and methods of use|
|US20100241410 *||Mar 17, 2010||Sep 23, 2010||Smith International, Inc.||Relative and Absolute Error Models for Subterranean Wells|
|US20140305704 *||Jun 25, 2014||Oct 16, 2014||Hunt Advanced Drilling Technologies, L.L.C.||System and method for surface steerable drilling|
| || |
|U.S. Classification||703/10, 175/45, 702/9, 73/152.46|
|International Classification||E21B47/022, E21B7/10, E21B1/00, E21B7/06, E21B44/00, E21B7/04|
|Cooperative Classification||E21B7/10, E21B47/022, E21B7/04, E21B44/00, E21B7/06|
|European Classification||E21B7/04, E21B7/06, E21B47/022, E21B7/10, E21B44/00|
|Apr 16, 2014||FPAY||Fee payment|
Year of fee payment: 8
|May 3, 2010||FPAY||Fee payment|
Year of fee payment: 4