EP0285505A1 - Verfahren und Vorrichtung zur Steuerung der Bahn eines Bohrmeissels an einem Bohrstrang - Google Patents

Verfahren und Vorrichtung zur Steuerung der Bahn eines Bohrmeissels an einem Bohrstrang Download PDF

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Publication number
EP0285505A1
EP0285505A1 EP88400712A EP88400712A EP0285505A1 EP 0285505 A1 EP0285505 A1 EP 0285505A1 EP 88400712 A EP88400712 A EP 88400712A EP 88400712 A EP88400712 A EP 88400712A EP 0285505 A1 EP0285505 A1 EP 0285505A1
Authority
EP
European Patent Office
Prior art keywords
stabilizers
drill string
stabilizer
piston
support
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP88400712A
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English (en)
French (fr)
Inventor
André Cendre
Jean Boulet
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
S M F International
SMF International
Original Assignee
S M F International
SMF International
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by S M F International, SMF International filed Critical S M F International
Publication of EP0285505A1 publication Critical patent/EP0285505A1/de
Withdrawn legal-status Critical Current

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Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B7/00—Special methods or apparatus for drilling
    • E21B7/04—Directional drilling
    • E21B7/06—Deflecting the direction of boreholes
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
    • E21B17/10—Wear protectors; Centralising devices, e.g. stabilisers
    • E21B17/1014—Flexible or expansible centering means, e.g. with pistons pressing against the wall of the well

Definitions

  • the invention relates to a method for adjusting the trajectory of a drilling tool attached to the end of a drill string.
  • stabilizers which are placed in spaced locations along the length of the drill string, in areas generally not far from the drilling tool.
  • Such stabilizers include a tubular body connected to the drill string, the central bore of which is in the extension of the bore of the rods, to ensure continuous circulation of the drilling fluid in the drill string.
  • the stabilizer body carries at least one support blade and generally three 120 ° support blades mounted movably on the stabilizer body, in radial directions relative to the axis of the drill string.
  • a means of actuating the support blades makes it possible to move these blades by extraction or retraction in a radial direction, in order to put them in a determined position where these blades are more or less protruding relative to the body of the stabilizer.
  • the blades which come to rest on the edges of the borehole allow the trajectory of the drilling tool to be adjusted.
  • Such a device is actuated by a control means having the drilling fluid as an energy source.
  • This control means can advantageously be produced in the form described in French patent application 85-00142 of January 7, 1985, published under the number 2.575.793.
  • the displacements of the piston ensuring the extraction of the support blades result in a very large increase in the pressure drop in the drilling fluid, so that it is possible to determine from the surface, by pressure measurements of the drilling fluid, the successive positions of the piston and therefore of the support blades.
  • the object of the invention is therefore to propose a method for adjusting the trajectory of a drilling tool fixed to the end of a drill string comprising at least two stabilizers arranged spaced apart along the length of the drill string and each comprising a body connected to the drill string, to the at least one support blade mounted to move on the stabilizer body in a radial direction relative to the drill string and means for actuating the support blade to move it between at least two stable positions of radial extraction relative to to the body, this process allowing fine adjustment of the path of the tool by increasing the number of possible configurations of all of the stabilizers, as regards the radial extraction of their support blades.
  • each of the stabilizers are controlled independently of one another, so as to place the support blades of these stabilizers in determined positions constituting, for all of the stabilizers associated with the drill string , a combination of support blade extraction positions ensuring a desired direction adjustment of the drill string.
  • Figure 1 we see the lower part of a drill string 1 comprising successive rods 1a, 1b, 1c of tubular shape in which flows the drilling mud, in the direction of the arrow che 2.
  • the lower rod 1c carries the drilling tool 4 which is rotated by the drill string 1 and thus ensures the drilling of the drilling hole 3.
  • a first stabilizer 5 is placed between the rods 1a and 1b and a second stabilizer between the rods 1b and 1c.
  • the stabilizers 5 and 6 are of the type described in patent application 85-04996.
  • Each of the stabilizers comprises a body 10 on which are mounted support blades 9 which can be inclined relative to the axis 11 of the drill string corresponding to the axis of the borehole.
  • each of the stabilizers comprises four support blades placed at 90 ° from each other around the body 10 of the corresponding stabilizer.
  • the support blades 9 are mounted movable relative to the body 10, in radial directions, that is to say directions perpendicular to the axis 11.
  • the characteristics of the stabilizers will be chosen so as to allow independent adjustment of the two stabilizers at a distance, as will be described below.
  • the stabilizers 5 and 6 are of the type described in French patent 2,579,662, FIG. 2 of the present patent application essentially reproducing FIG. 2 of the previous French patent application mentioned above.
  • the body 10 of the tubular stabilizer has an internal bore 12 in the extension of the internal bore of the drill string, to ensure continuous circulation of the drilling fluid, in the axial direction 2.
  • the body 10 can be connected directly or via junction pieces to the rods of the drill string, both on the upstream side and on the downstream side, if we consider the direction of circulation (arrow 2) of the drilling fluid .
  • the blades 9 are mounted movable in radial directions, relative to the body 10 of the stabilizer and held by means of holding pieces 13.
  • the blades are returned to the retracted position by means of leaf springs 14.
  • Each of the blades can be moved in the radial direction, by means of fingers 15 slidably mounted in the body 10 of the stabilizer and in contact with the blade 9 by one of their ends.
  • a tubular actuating piston 16 is mounted movable both in axial translation and in rotation about the axis 11 inside the bore 12 of the body 10.
  • the piston 16 is machined on its external lateral surface, to constitute ramps 17 inclined in a radial direction relative to the axis 11 of the drill string.
  • the fingers 15 are engaged with the ramps 17 by their end opposite their end coming into contact with the inner face of the support blade 9.
  • a movement of the piston 16 to the right in FIG. 2 causes an extraction movement, that is to say a radial and outward movement of the fingers 15 and the support blades 9.
  • ramps 17 of variable inclination are machined all around the piston 16 and are connected by complementary parts at constant level in the radial direction which include straight parts returning the piston 16 and curved parts making it possible to rotate the piston inside the bore 12 so that it takes a step making it possible to present the fingers of the support blades at the entry of a new ramp.
  • a freewheel 20 authorizing the rotation of the piston in one direction makes it possible to ensure a determined sequence of the positions of extraction of the support blades, by successive displacements of the piston in the bore 12; the extraction sequence is determined by the shape of the actuation surface and in particular by the inclination and the position of the ramps 17.
  • the displacements of the piston in axial translation in the direction of arrow 2 are controlled by a pressure drop device constituted by a profiled body 21 of axial direction called needle and an annular profiled part 23.
  • the needle 21 is fixed on the body 10, along the axis of the bore 12 and the annular part 23 is integral with the tubular piston 16 of which it constitutes a part of the interior surface in which the drilling fluid circulates.
  • the piston 16 is mounted in the body 10 so that the part 23 is placed around the needle 21.
  • the drilling fluid circulating in the direction of the arrow 2 must pass, on entering the tubular piston 16, in the annular space formed between the needle 21 and the annular part 23. This results in a pressure drop which is translated by a pressure difference on either side of the piston 16 in the axial direction.
  • the piston 16 is held in its position shown in FIG. 2, the fingers 15 being in contact with the ramps 17 at one of their ends, both by a helical return spring 24 and the leaf springs 14 of the blades support 9 acting on the piston 16, by means of the fingers 15.
  • the characteristics of the stabilizer and in particular the diameters of the needle 21 and of the annular part 23 are determined so that the displacement of the piston in the axial direction and in the direction of the arrow 2 occurs for a actuating flow rate Qact1 clearly higher than the normal Qfor drilling rate.
  • the operation of the device is therefore as follows: when it is desired to move the support blades 9, for example for their extraction, the flow rate of the drilling fluid is raised to a value at least equal to Qact1 and generally a little higher.
  • the piston 16 then moves in the direction of arrow 2, which produces an extraction of the blades by interaction of the fingers 15 and the ramps 17.
  • the length of displacement of the piston 16 corresponds to the length of the ramps, so that end of displacement of the piston, the fingers 15 have reached the left end of the ramps 17.
  • the increasing diameter profile of the needle 21 cooperates, during the displacement of the piston, with the annular part 23, to increase the pressure drop in the drilling fluid.
  • the pressure of the drilling fluid which can be measured from the surface increases considerably at the end of the translational movement of the piston. It is thus possible to identify from the surface, the position of the piston corresponding to the position of the fingers at the end of the ramps.
  • the fingers 15 then come into contact with a curved part of the actuating surface which produces a rotation of the piston 16 around the axis 11, in the direction desired by the freewheel 20, according to a pitch of rotation.
  • the fingers 15 are then in alignment with complementary parts at constant level of the actuating surface.
  • the fingers 15 describe complementary parts at constant level of the action surface to come into a stable position whose level corresponds to the level of the left end of the ramps 17.
  • the support blades are then held in a stable extraction position by the fingers 15.
  • the drilling flow is restored in the drill string and drilling is continued, the trajectory adjustment of which is ensured by the stabilizer 5 in the extraction position.
  • the device described by way of example in patent 2,579,662 thus comprises three stable positions for extracting the support blades 9.
  • the second stabilizer 6 comprises a needle 21 ⁇ identical to the needle 21 of the device for actuating the first stabilizer 5.
  • the device for actuating the second stabilizer 6 comprises an annular part 23 ⁇ secured to its piston 16 ⁇ whose minimum internal diameter is substantially greater than the minimum internal diameter d of the annular part 23 of the actuator device for the stabilizer 5.
  • the actuation flow Qact2 of the stabilizer 6 is greater than the ac flow operation Qact1 of the stabilizer 5, the variable pressure drop with the flow rate being greater at the level of the annular passage section with outside diameter d, than at the level of the annular passage section with outside diameter d ⁇ .
  • the actuators of the stabilizers 5 and 6 as just described make it possible to adjust the stabilizers 5 and 6 independently of one another in one of their extraction positions, as will be described below. below.
  • osses 1, ⁇ 2 and ⁇ 3 will be designated the outside diameters of the stabilizer 5, the blades of which have been placed in their three successive extraction positions respectively. These diameters correspond to the three possible configurations of the stabilizer 5.
  • the stabilizer 5 has been placed in one of these configurations, for example the configuration ⁇ 2, by the process described above.
  • the position ⁇ 2 is reached, the drilling flow is canceled, the piston 16 of the stabilizer 5 then returns to its starting position. The stabilizer 5 is then in its stable position corresponding to the configuration ⁇ 2.
  • the flow rate of the drilling fluid is then increased, from the surface, to a value at least equal to Qact2 and generally a little higher.
  • the pistons 16 and 16 ⁇ then move so as to put the support blades of the stabilizers 5 and 6 in new positions. After canceling the flow, the stabilizers 5 and 6 are in new positions stable corresponding for example to the configurations ⁇ 3 and ⁇ 1, respectively.
  • the stabilizers are continued to be actuated by raising the actuation flow to a level greater than Qact1 and less than Qact2 or to a level greater than Qact2.
  • the combination ⁇ 2 ⁇ 2 we will successively carry out the following operations: - increase in flow to Qact2 (or slightly above), - cancellation of flow (the combination obtained is then ⁇ 1 ⁇ 2), - increase in flow to Qact1, - cancellation of the flow (the combination obtained is then ⁇ 2 ⁇ 2).
  • the successive positions of the pistons 16 and 16 ⁇ can be identified from the surface, by pressure measurement, the pressure drop between the parts 23 and 23 ⁇ and the needles 21 and 21 ⁇ , respectively being very high when the piston has finished moving under the effect of drilling fluid.
  • the independent adjustment of the configurations of the stabilizers 5 and 6 makes it possible to obtain nine different combinations associating a configuration of the stabilizer 5 with a configuration of the stabilizer 6.
  • the three different configurations for extracting the blades from the stabilizer corresponded to levels of the actuation surface situated respectively at 11 mm, 6 mm and 4.5 mm. below the nominal exterior surface of the stabilizer piston.
  • the same actuation levels will be chosen, so that the diameters ⁇ 1, ⁇ 2, ⁇ 3 and ⁇ 1, ⁇ 2 and ⁇ 3 will be respectively equal to: D, D + 10 mm, D + 13 mm if D denotes the minimum diameter of the stabilizer.
  • the method according to the invention therefore has the advantage of allowing great latitude for adjusting the drilling trajectory, with a reduced number of stabilizers which can be equal to two, each of the stabilizers themselves having a number of adjustment configurations. which can be reduced.
  • a set of two stabilizers will be used, each having two different adjustment positions.
  • the method according to the invention is not limited to the use of a hydraulic control of the pressure drop type, to ensure the actuation of the various stabilizers placed in series.
  • a hydraulic control of the pressure drop type to ensure the actuation of the various stabilizers placed in series.
  • Other hydraulic type controls for example using valves or shutters which are introduced into the drill string for actuation of the stabilizers.
  • such devices are less flexible and less easy to use than pressure drop devices controlled from the surface.
  • the stabilizers can be of a different type from that which has been described in patent application 85-04996 and comprise, for example, pistons moving only in translation and having extraction ramps for the blades actuating fingers. support aligned along the length of the piston.
  • the invention applies in all cases where it is desired to adjust and control the trajectory of a drilling tool.

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  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • Physics & Mathematics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Mechanical Engineering (AREA)
  • Earth Drilling (AREA)
  • Drilling Tools (AREA)
  • Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
  • Drilling And Boring (AREA)
EP88400712A 1987-03-27 1988-03-23 Verfahren und Vorrichtung zur Steuerung der Bahn eines Bohrmeissels an einem Bohrstrang Withdrawn EP0285505A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8704322A FR2612985B1 (fr) 1987-03-27 1987-03-27 Procede et dispositif de reglage de la trajectoire d'un outil de forage fixe a l'extremite d'un train de tiges
FR8704322 1987-03-27

Publications (1)

Publication Number Publication Date
EP0285505A1 true EP0285505A1 (de) 1988-10-05

Family

ID=9349515

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88400712A Withdrawn EP0285505A1 (de) 1987-03-27 1988-03-23 Verfahren und Vorrichtung zur Steuerung der Bahn eines Bohrmeissels an einem Bohrstrang

Country Status (6)

Country Link
US (1) US4848488A (de)
EP (1) EP0285505A1 (de)
JP (1) JPS63308182A (de)
BR (1) BR8801386A (de)
FR (1) FR2612985B1 (de)
NO (1) NO881335L (de)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0594420A1 (de) * 1992-10-23 1994-04-27 Halliburton Company Einstellbarer Bohrstrangstabilisator
EP0594419A1 (de) * 1992-10-23 1994-04-27 Halliburton Company Stabilisator mit einstellbaren Flügeln für Bohrsystem
GB2357101A (en) * 1999-12-10 2001-06-13 Baker Hughes Inc Simultaneous Drilling and Casing Of Wellbores

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ATE32930T1 (de) * 1985-01-07 1988-03-15 Smf Int Durchflussferngesteuerte vorrichtung zum betaetigen insbesondere von stabilisatoren in einem bohrstrang.
FR2641315B1 (fr) * 1988-12-30 1996-05-24 Inst Francais Du Petrole Garniture de forage a trajectoire controlee comportant un stabilisateur a geometrie variable et utilisation de cette garniture
FR2641317B1 (fr) * 1988-12-30 1996-05-24 Inst Francais Du Petrole Equipement pour garniture de forage comportant un element a actionner, un moteur et des moyens de commande
US5141060A (en) * 1989-11-01 1992-08-25 Teleco Oilfield Services Inc. Method for optimizing of stabilizer positioning in a bottomhole assembly to eliminate the effects of borehole inclination
US5265684A (en) * 1991-11-27 1993-11-30 Baroid Technology, Inc. Downhole adjustable stabilizer and method
US5311953A (en) * 1992-08-07 1994-05-17 Baroid Technology, Inc. Drill bit steering
US5332048A (en) * 1992-10-23 1994-07-26 Halliburton Company Method and apparatus for automatic closed loop drilling system
GB9503827D0 (en) * 1995-02-25 1995-04-19 Camco Drilling Group Ltd "Improvements in or relating to steerable rotary drilling systems
US5609178A (en) * 1995-09-28 1997-03-11 Baker Hughes Incorporated Pressure-actuated valve and method
US6328119B1 (en) 1998-04-09 2001-12-11 Halliburton Energy Services, Inc. Adjustable gauge downhole drilling assembly
CA2234495C (en) * 1998-04-09 2004-02-17 Dresser Industries, Inc. Adjustable gauge downhole drilling assembly
US7136795B2 (en) 1999-11-10 2006-11-14 Schlumberger Technology Corporation Control method for use with a steerable drilling system
US6601658B1 (en) 1999-11-10 2003-08-05 Schlumberger Wcp Ltd Control method for use with a steerable drilling system
US7188685B2 (en) 2001-12-19 2007-03-13 Schlumberge Technology Corporation Hybrid rotary steerable system
GB2405483B (en) 2002-05-13 2005-09-14 Camco Internat Recalibration of downhole sensors
US7681665B2 (en) * 2008-03-04 2010-03-23 Smith International, Inc. Downhole hydraulic control system
US7878272B2 (en) * 2008-03-04 2011-02-01 Smith International, Inc. Forced balanced system

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3298449A (en) * 1963-10-24 1967-01-17 Drilco Oil Tools Inc Well bore apparatus
GB2077811A (en) * 1980-06-12 1981-12-23 Shirley Kirk Risinger A steering tool adapted to control the angle and direction of a rotary well drilling string in the drilling of a well bore through earth formation
US4491187A (en) * 1982-06-01 1985-01-01 Russell Larry R Surface controlled auxiliary blade stabilizer
FR2575793A1 (fr) * 1985-01-07 1986-07-11 Smf Int Dispositif d'actionnement a distance d'un equipement associe a un conduit dans lequel circule un fluide incompressible
FR2579662A1 (fr) * 1985-04-02 1986-10-03 Smf Int Dispositif de forage a trajectoire controlee
US4635736A (en) * 1985-11-22 1987-01-13 Shirley Kirk R Drill steering apparatus

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3424256A (en) * 1967-01-10 1969-01-28 Whipstock Inc Apparatus for controlling directional deviations of a well bore as it is being drilled
US3593810A (en) * 1969-10-13 1971-07-20 Schlumberger Technology Corp Methods and apparatus for directional drilling
GB8302270D0 (en) * 1983-01-27 1983-03-02 Swietlik G Drilling apparatus

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3298449A (en) * 1963-10-24 1967-01-17 Drilco Oil Tools Inc Well bore apparatus
GB2077811A (en) * 1980-06-12 1981-12-23 Shirley Kirk Risinger A steering tool adapted to control the angle and direction of a rotary well drilling string in the drilling of a well bore through earth formation
US4491187A (en) * 1982-06-01 1985-01-01 Russell Larry R Surface controlled auxiliary blade stabilizer
FR2575793A1 (fr) * 1985-01-07 1986-07-11 Smf Int Dispositif d'actionnement a distance d'un equipement associe a un conduit dans lequel circule un fluide incompressible
FR2579662A1 (fr) * 1985-04-02 1986-10-03 Smf Int Dispositif de forage a trajectoire controlee
US4635736A (en) * 1985-11-22 1987-01-13 Shirley Kirk R Drill steering apparatus

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0594420A1 (de) * 1992-10-23 1994-04-27 Halliburton Company Einstellbarer Bohrstrangstabilisator
EP0594419A1 (de) * 1992-10-23 1994-04-27 Halliburton Company Stabilisator mit einstellbaren Flügeln für Bohrsystem
GB2357101A (en) * 1999-12-10 2001-06-13 Baker Hughes Inc Simultaneous Drilling and Casing Of Wellbores
GB2357101B (en) * 1999-12-10 2002-07-17 Baker Hughes Inc Apparatus and method for simultaneous drilling and casing wellbores

Also Published As

Publication number Publication date
US4848488A (en) 1989-07-18
FR2612985B1 (fr) 1989-07-28
FR2612985A1 (fr) 1988-09-30
NO881335L (no) 1988-09-28
JPS63308182A (ja) 1988-12-15
BR8801386A (pt) 1988-11-01
NO881335D0 (no) 1988-03-25

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