EP0327925B1 - Vorrichtung zum wahlweisen Geradeaus- oder Richtungsbohren in unterirdische Gesteinsformationen - Google Patents

Vorrichtung zum wahlweisen Geradeaus- oder Richtungsbohren in unterirdische Gesteinsformationen Download PDF

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Publication number
EP0327925B1
EP0327925B1 EP89101615A EP89101615A EP0327925B1 EP 0327925 B1 EP0327925 B1 EP 0327925B1 EP 89101615 A EP89101615 A EP 89101615A EP 89101615 A EP89101615 A EP 89101615A EP 0327925 B1 EP0327925 B1 EP 0327925B1
Authority
EP
European Patent Office
Prior art keywords
stabilising
rotary
housing
bit
drilling tool
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.)
Expired - Lifetime
Application number
EP89101615A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0327925A1 (de
Inventor
Volker Dr.-Ing. Krüger
Johannes Dipl.-Ing. Witte
Rainer Dr.-Ing. Jürgens
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.)
Baker Hughes Oilfield Operations LLC
Original Assignee
Eastman Christensen Co
Eastman Teleco Co
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 Eastman Christensen Co, Eastman Teleco Co filed Critical Eastman Christensen Co
Publication of EP0327925A1 publication Critical patent/EP0327925A1/de
Application granted granted Critical
Publication of EP0327925B1 publication Critical patent/EP0327925B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime 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
    • E21B7/068—Deflecting the direction of boreholes drilled by a down-hole drilling motor

Definitions

  • the invention relates to a device for drilling a borehole with a choice of a straight or curved center line in underground rock formations according to the preamble of claim 1.
  • a first known device In order to create a deflection angle for the axis of rotation of the chisel shaft during directional drilling, which is also decisive for the build-up rate that can be achieved, in a first known device (EP-OS 45 444) the first and the second stabilizer are arranged eccentrically on a straight tube-shaped housing of the rotary drilling tool. Such a design imprints the housing in the directional drilling operation a deflection that is decisive for the deflection angle.
  • a second known device in the case of stabilizers arranged concentrically on the housing of the rotary drilling tool, the housing is provided with regions which are deflected with respect to the main axis of the tool and which define two oppositely directed kink points which jointly determine the deflection angle.
  • the deflection of the housing areas can be designed such that only a single kink defines the deflection angle between the two stabilizers.
  • a kink between the rotary drill bit and the first stabilizer is provided in a third known device of the type mentioned (EP-PS 0 109 699, DE-PS 33 26 855 ).
  • This kink is formed in that the chisel shaft is mounted at an angle to the axis of the straight tubular housing in the lower region thereof and exits the housing end at an angle.
  • the chisel shaft is mounted in the housing of the rotary drilling tool with an axis of rotation offset laterally parallel to the housing axis.
  • the invention is based on the object of designing a device of the generic type in such a way that its rotary drilling tool provides a higher course accuracy and, with reduced wear, a higher drilling performance when directional drilling.
  • the special alignment of the axis of its chisel shaft gives the rotary drill bit a guide which is substantially relieved of the resultant lateral forces during directional drilling, with the consequence of less wear and tear and a higher drilling capacity.
  • the device according to the invention illustrated in a schematic overview in FIG. 1 comprises a rotary drilling tool 2 located in a borehole 1, the housing 3 of which is connected at its upper end to a drill pipe string 4.
  • the drill pipe string 4 is clamped in a turntable 5 of a drilling tower 6.
  • the turntable 5 is provided with a drive and blocking device 7, by means of which the chuck of the turntable 5 and thus the drill pipe string 4 can be set in continuous self-rotation or aligned and then by a limited rotary movement can be fixed against rotation.
  • the first embodiment of a rotary drilling tool 2 illustrated in FIGS. 1 to 4 has a housing 3 consisting of a plurality of parts or sections 8, 9, 10, 11, 12 screwed to one another.
  • the housing part 10 is formed over part of its length as a stator 13 of a deep-hole motor with a rotor 14.
  • the deep-hole motor 13, 14 in the exemplary embodiment illustrated in FIGS. 3 and 4 is a displacement motor operating according to the Moineau principle, but can also be formed by a turbine or a motor of another suitable construction.
  • the rotor 14 is connected by means of an articulated shaft 15 arranged in the housing part 11 to the upper end of a chisel shaft 16, which is rotatably mounted in bearings 17, 18 of the housing part 12 forming a bearing bracket and, in the embodiment of the rotary drilling tool according to FIGS 19 which encloses a small angle with the housing axis 20 of the housing part 12.
  • the chisel shaft 16, which is provided with a rotary drill bit 21 at its outer end emerges obliquely from the lower end of the housing 3.
  • the rotary drilling tool 2 In its lower region near the rotary drill bit 21, the rotary drilling tool 2 has a first stabilization point 22 in the form of a stabilizer 24 attached to the housing part 12 with a number of stabilizer wings or ribs distributed over the circumference. At a distance above this first stabilization point 22, the rotary drilling tool 2 has a second stabilization point 25, which is likewise formed by a conventional stabilizer 24 arranged on the housing part 8.
  • the imaginary centers of these stabilization points 22, 25, together with an imaginary center point of the rotary drill bit, define the course of an imaginary center line for the borehole 1, which has an arcuate course in regions of the borehole 1 drilled during directional drilling work, which approximately forms part of an arc.
  • the center line, not shown in the drawing for reasons of clarity, of the region of the borehole 1 which is always shown curved in FIGS. 2 and 5 to 11 has its base point at 26 and an arc center which is located far beyond the right edge of the drawing.
  • ⁇ denotes the angle that opens towards the rotary drill bit 21 between the imaginary connecting line of the center point (coinciding with the base point 26) of the rotary drill bit 21 with the imaginary center point of the borehole at the level of the first stabilization point 22 and an imaginary lower extension of the straight connecting line of the imaginary center points of the borehole 1 at the level of the first and the second stabilization point 22, 25.
  • l denotes the distance between the imaginary center of the second stabilization point 25 and the mentioned center of the rotary drill bit 21.
  • a build-up rate of at least approximately 2 ° / 30 m is preferred, corresponding to a distance of the arc center to the center line of the borehole of approximately 850 m.
  • the rotary drilling tool 2 like all other illustrated or conceivable embodiments according to the invention, has a design which, when drilling the direction of the axis of rotation 19 of the chisel shaft 16, has an orientation to an imaginary straight connecting line 28 between the arc center and the base point 26 of the arcuate center line of the rotary drilling tool specifies drillable borehole 1 at an angle of attack ⁇ of 90 ° as the upper limit.
  • the axis of rotation 19 of the bit shaft 16 forms a tangent to the arcuate center line of the borehole 1 at the level of the base point 26, with the result that the resulting lateral forces on the rotary bit 21 are reduced to a minimum.
  • These side forces are substantially larger in the known devices, because in these the axis of rotation 19 of the chisel shaft 16 forms a secant to the arcuate center line of a borehole drilled during directional drilling with intersections with the center line which lie above the base point 26.
  • the angle of attack ⁇ can also be designed to be slightly smaller than 90 ° and between 89 ° and 90 °. This "lead" can compensate for bending deformations that a rotary drilling tool may possibly introduce when it is inserted into a partially drilled borehole, e.g. experienced in the course of a round trip.
  • a kink 29 is provided between the first and the second stabilization point 22, 25 and a further kink 30 in the area between the rotary drill bit 21 and the first stabilization point 22.
  • both kinks 29, 30 are assigned to the integral housing part 12 assigned to the lower stabilization point 22, and both kinks 29, 30 each have the same direction of kink toward the arc center.
  • the kink 29 is formed in the rotary drilling tool 2 by an inclined upper connecting thread part 31 of the housing part 12 and the second kink 30 from the inclined bearing 17, 18 of the chisel shaft 16 in the housing part 12.
  • the sum of the amounts of both articulation angles corresponds to the amount of the deflection angle ⁇ , and the build-up rate is calculated from both articulation angles.
  • the angular amounts can be divided differently, taking special account of the structural conditions.
  • the kink 29 is preferably used for determining the build-up rate, while the kink 30 mainly takes into account the desired angle of attack ⁇ .
  • the kink angle of the kink 29 can be 1.5 ° and above, while the kink angle of the kink 30 can be, for example, 0.6 ° or less.
  • the design according to the invention can also be implemented with a single kink instead of two or more than two kinks.
  • the provision of several kinks is generally preferable from the structural design of the rotary drilling tool, and the assignment of both kinks to a single housing part 12 provided in the rotary drilling tool 2 simplifies the construction, since all the housing parts 8 to 11 above it can be made in a straight tube shape.
  • FIG. 5 illustrates a second embodiment of a rotary drilling tool 102, in which a further kink 32 is provided between the first stabilization point 22 and the second stabilization point 25 in addition to the kink point 29.
  • the two kink points 29, 30 may have the same kink direction or opposite kink directions as in FIG. 5, the kink point 32 facing away from the arc center of the arcuate center line of the borehole 1 and the kink point 29 facing this drilling center.
  • Such a course of the bending directions reduces or avoids an eccentricity of the imaginary center of the rotary drill bit 21 to an imaginary straight lower extension of the upper part 27 of the main tool axis.
  • Such a course of the buckling direction is also preferable for bores with rotary drill bits 21 with a small diameter and a small free cut.
  • Both kinks 29, 32 are assigned to a housing part 11, which can be designed as an integral, bent-shaped part or can also have a three-part design with inclined threaded connection parts.
  • FIG. 6 illustrates a third embodiment of a rotary drilling tool 202, which is a modification of the rotary drilling tool 2 instead of the kink 29 has another kink 33 between the rotary drill bit 21 and the first stabilization point 22.
  • This further kink 33 like the kink 30, can be designed in accordance with the kinks 29, 30 (FIG. 2).
  • both kinks 30, 33 are assigned to the housing part 12, but the first stabilization point 22 is assigned to the housing part 11.
  • FIG. 7 illustrates a fourth embodiment of a rotary drilling tool 302, which essentially corresponds to that of FIG. 6 with the difference that the kink 33 has an opposite kink direction to the kink 30.
  • the kink 33 has a direction of turning away from the arch center and the lower kink 30 has a kink direction facing the arch center.
  • FIG. 8 illustrates a fifth embodiment of a rotary drilling tool 402, in which only one kink 29 corresponding to the kink 29 of the rotary drilling tool 2 is provided between the stabilization points 22, 25.
  • the lower stabilization point 22 is formed by a stabilizer 424, which has an undersize compared to a stabilizer designed in the normal dimension to a given rotary drill bit 21.
  • the rotary drilling tool 402 is provided with a chisel shaft 16 which is mounted coaxially in the housing part 12.
  • a sixth embodiment of a rotary drilling tool 502 according to FIG. 9 is similar to that according to FIG. 8 with the difference that the lower stabilization point 22 is formed by a stabilizer 524 arranged eccentrically on the housing part 12.
  • the seventh embodiment of a rotary drill bit 602 illustrated in FIG. 10 provides that the first stabilization point 22 is assigned to the rotary drill bit 21 and forms part of the same, for example by the molding of a stabilization part arranged downstream of the cutting part. Otherwise, the rotary drilling tool 602 has a single kink 29 between the two Stabilization points 22, 25, which can correspond structurally to the kink 29 according to FIG. 4.
  • FIG. 11 finally illustrates an eighth embodiment of a rotary drilling tool 702, in which the upper stabilization point 25 is not formed by a pronounced stabilizer of conventional design, but by a stabilization area of the housing 3 or its housing part 8 and at the same time with an undersize compared to a stabilizer designed in normal dimensions, in which the diameter in the limit case can correspond to the diameter of the housing 3 as shown.
  • the rotary drilling tool 702 as in the rotary drilling tool 2 according to FIG. 2, there is a kink 29 in the area between the stabilization points 22, 25 and a kink between the rotary drill bit 21 and the first stabilization point 22, the design of which can correspond to that of the rotary drilling tool 4.
  • Stabilizers with or without undersize, stabilization areas, eccentric stabilizer arrangements, kinks, their number and location, bearings of the chisel shaft 16 in the housing part 12 with a rotational axis offset parallel to the housing axis 20 form all structural parameters that can be combined with one another in order to form a rotary drilling tool
  • an alignment angle ⁇ of 90 ° as the highest limit.
  • kink points that define a predetermined kink angle, as is the case with the inclined bearing 17, 18 of the chisel shaft 16 or with inclined connecting thread parts 31, kink points can also be provided which only develop in directional drilling operation under load in special housing areas on which the kink formation is limited due to a particularly predetermined flexibility.

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Earth Drilling (AREA)
  • Drilling And Boring (AREA)
EP89101615A 1988-02-12 1989-01-31 Vorrichtung zum wahlweisen Geradeaus- oder Richtungsbohren in unterirdische Gesteinsformationen Expired - Lifetime EP0327925B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3804493 1988-02-12
DE3804493A DE3804493A1 (de) 1988-02-12 1988-02-12 Vorrichtung zum wahlweisen geradeaus- oder richtungsbohren in unterirdische gesteinsformationen

Publications (2)

Publication Number Publication Date
EP0327925A1 EP0327925A1 (de) 1989-08-16
EP0327925B1 true EP0327925B1 (de) 1992-12-09

Family

ID=6347333

Family Applications (1)

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EP89101615A Expired - Lifetime EP0327925B1 (de) 1988-02-12 1989-01-31 Vorrichtung zum wahlweisen Geradeaus- oder Richtungsbohren in unterirdische Gesteinsformationen

Country Status (7)

Country Link
US (1) US5099931A (da)
EP (1) EP0327925B1 (da)
AU (1) AU617420B2 (da)
CA (1) CA1317929C (da)
DE (1) DE3804493A1 (da)
DK (1) DK61489A (da)
NO (1) NO302770B1 (da)

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FI80780C (fi) * 1987-06-17 1990-07-10 Ahlstroem Oy Foerfarande och anordning foer torkning av partikelformigt material.
US5139094A (en) * 1991-02-01 1992-08-18 Anadrill, Inc. Directional drilling methods and apparatus
US5458208A (en) * 1994-07-05 1995-10-17 Clarke; Ralph L. Directional drilling using a rotating slide sub
US5542482A (en) * 1994-11-01 1996-08-06 Schlumberger Technology Corporation Articulated directional drilling motor assembly
US5727641A (en) * 1994-11-01 1998-03-17 Schlumberger Technology Corporation Articulated directional drilling motor assembly
US5738178A (en) * 1995-11-17 1998-04-14 Baker Hughes Incorporated Method and apparatus for navigational drilling with a downhole motor employing independent drill string and bottomhole assembly rotary orientation and rotation
CA2213536A1 (en) * 1996-08-22 1998-02-22 Baker Hughes Incorporated Intermediate radius steerable tool
US5765653A (en) * 1996-10-09 1998-06-16 Baker Hughes Incorporated Reaming apparatus and method with enhanced stability and transition from pilot hole to enlarged bore diameter
US5957223A (en) * 1997-03-05 1999-09-28 Baker Hughes Incorporated Bi-center drill bit with enhanced stabilizing features
US6109371A (en) * 1997-03-23 2000-08-29 The Charles Machine Works, Inc. Method and apparatus for steering an earth boring tool
US6102138A (en) * 1997-08-20 2000-08-15 Baker Hughes Incorporated Pressure-modulation valve assembly
US6269892B1 (en) * 1998-12-21 2001-08-07 Dresser Industries, Inc. Steerable drilling system and method
US6622803B2 (en) 2000-03-22 2003-09-23 Rotary Drilling Technology, Llc Stabilizer for use in a drill string
US6739416B2 (en) * 2002-03-13 2004-05-25 Baker Hughes Incorporated Enhanced offset stabilization for eccentric reamers
US7311157B1 (en) 2005-05-31 2007-12-25 Rpm Tools, Inc. Tool for controlling rotation of a bottom hole assembly with respect to a drillstring
CA2769141C (en) * 2011-03-08 2016-07-12 Drilformance Technologies, Llc Drilling apparatus
CN103556945B (zh) * 2013-10-27 2015-07-01 长江大学 一种高造斜率井眼轨迹控制方法
EP3656969B1 (en) * 2014-12-29 2021-07-14 Halliburton Energy Services, Inc. Drilling assembly having a tilted or offset driveshaft
US10655394B2 (en) 2015-07-09 2020-05-19 Halliburton Energy Services, Inc. Drilling apparatus with fixed and variable angular offsets
US10890030B2 (en) 2016-12-28 2021-01-12 Xr Lateral Llc Method, apparatus by method, and apparatus of guidance positioning members for directional drilling
US11255136B2 (en) * 2016-12-28 2022-02-22 Xr Lateral Llc Bottom hole assemblies for directional drilling

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Also Published As

Publication number Publication date
DK61489A (da) 1989-08-13
NO302770B1 (no) 1998-04-20
EP0327925A1 (de) 1989-08-16
NO890599L (no) 1989-08-14
DE3804493C2 (da) 1990-01-25
NO890599D0 (no) 1989-02-10
CA1317929C (en) 1993-05-18
DE3804493A1 (de) 1989-08-24
US5099931A (en) 1992-03-31
DK61489D0 (da) 1989-02-10
AU2956489A (en) 1989-08-17
AU617420B2 (en) 1991-11-28

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