EP0163946B1 - Apparatus for optional straight or directional drilling underground formations - Google Patents

Apparatus for optional straight or directional drilling underground formations Download PDF

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Publication number
EP0163946B1
EP0163946B1 EP85105353A EP85105353A EP0163946B1 EP 0163946 B1 EP0163946 B1 EP 0163946B1 EP 85105353 A EP85105353 A EP 85105353A EP 85105353 A EP85105353 A EP 85105353A EP 0163946 B1 EP0163946 B1 EP 0163946B1
Authority
EP
European Patent Office
Prior art keywords
section
housing
stabiliser
angle
axis
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
Application number
EP85105353A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0163946A1 (en
Inventor
Rolf Panzke
Volker Dr.-Ing. Krüger
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
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
Priority claimed from DE19843417743 external-priority patent/DE3417743C1/de
Priority claimed from DE19843423465 external-priority patent/DE3423465C1/de
Application filed by Eastman Christensen Co filed Critical Eastman Christensen Co
Publication of EP0163946A1 publication Critical patent/EP0163946A1/en
Application granted granted Critical
Publication of EP0163946B1 publication Critical patent/EP0163946B1/en
Expired 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
    • 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
    • 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
    • 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
    • E21B7/10—Correction of deflected boreholes

Definitions

  • This invention relates to apparatus for selective straight or directional drilling underground formations.
  • a device capable of being used for directional drilling only is already described in GB-A-0 636 879 and including a drill string unrotatably fixed during drilling operations and a housing for down-hole motor having an output shaft for connecting to a drill bit.
  • the axis of the rotating drill bit is displaced angularly from the main axis of the drill string by means of a bent thick-walled drilling tube connecting the lower end of the drill string and the upper end of the housing.
  • US-A-3 260 318 describes a device which also is only capable of being used for a directional drilling comprising a tubular housing con- nectably to the lower end of a drill string unrotat- able fixed during drilling operations and a down-hole motor mounted in said housing and having an output shaft for connecting to a drill bit, said housing having an upper section, an intermediate section and a lower section connected to one another.
  • the intermediate section surrounding the universal joint connection between the rotor of the down-hole motor mounted in the upper section of said housing and the output shaft journalled in the lower section has a bent configuration so that its two ends are angularly related to each other.
  • European Patent Application No. 83 20 0027 published with No. 0085444 describes a device which is capable of being used for straight drilling or for drilling at an angle. In particular it describes a method and means for controlling the course of a bore-hole during drilling.
  • the method and means include first and second stabilisers which are arranged to support the housing for a down-hole motor having an output shaft for connecting to a drill bit. At least one of the stabilisers is eccentric relative to the housing so that the housing will be bent at drilling without rotation of the housing. Bending of the housing will cause a change in the angle of the axis of the output shaft of the down-hole motor causing in turn drilling at an angle relative to the straight drilling direction being effected by a slow rotation of the housing.
  • first and second stabilisers which are arranged to support the housing for a down-hole motor having an output shaft for connecting to a drill bit. At least one of the stabilisers is eccentric relative to the housing so that the housing will be bent at drilling without rotation of the housing. Bending of the housing will cause a change in the angle of the axis of the output shaft of the down-hole motor causing in turn drilling at an angle relative to the straight drilling direction being effected by a slow rotation of the housing.
  • the bending of the housing causes stresses to be introduced into the housing which are transmitted to the drill bit causing excessive friction between the drill bit and the wall of the bore-hole. Furthermore additional strains are imposed on the stabilisers, the connections between the drill string and the housing, between the down-hole motor output shaft and the drill bit and between sections of the housing. These stresses can lead to damage and/or excessive wear of bearings.
  • a device for selective straight or directional drilling of boreholes in underground formations comprising a tubular housing, a down-hole motor mounted in said housing and having an output shaft, means for connecting said output shaft to a drill bit, means for connecting said housing to a drill string, first and second stabilisers mounted on said housing, said housing comprising an upper section and a lower section connected to one another, said first stabiliser being associated with said lower section of said housing and said second stabiliser being associated with said upper section of said housing, said upper section having a longitudinal axis being the main axis of the device and said lower section having a longitudinal axis which is arranged at an angle relative to the axis of said upper section, and an intermediate section is provided between the lower end of said upper section and the upper end of said lower section having a longitudinal axis which intersects said upper and lower section axes.
  • the upper and lower sections of the housing are connected to the intermediate section by angled connectors, especially threaded connectors.
  • said intermediate section includes a plurality of. interchangeable elements whereby the angle between the axes of the upper and lower housing sections can be preset. Conveniently the length of the intermediate section when preset at one angle is different from the length of the intermediate section when set at a different angle.
  • the lower housing section is provided with a connecting portion which is set at an angle relative to the lower section axis which is determined by the preset angle to the intermediate section.
  • the position of the first and/or second stabilisers can be adjustable relative to the lower housing section and/or upper housing section respectively.
  • At least the first stabiliser had adjustable eccentricity.
  • Suitable stabilisers having adjustable eccentricity are described in German Patent Application No. P34 03 239.8-24.
  • the device shown in Fig. 1 incorporates the concepts of European Patent Application No. 0085444 the disclosure of which is included herein by reference.
  • the drilling device 2 is shown in position in a bore-hole 1. It comprises a housing 3 connected to a drill string 4 by means not shown.
  • the connecting means may be a screw threaded arrangement as shown in European Patent Application No. 0085444.
  • the drill string 4 is arranged to be rotated by a turntable 5 having a locking device 7 to prevent rotation of the turntable 5 and drill string 4.
  • the turntable 5 and locking device 7 are mounted on a derrick 6.
  • the locking device 7 controls the rotation of the drill string 4 to permit, for example continuous rotation or limited rotation for alignment purposes. When the locking device is in its locking condition it prevents rotation of the drill string 4 and the housing 3.
  • the alternative embodiments of the drilling device 2, shown in Figs. 2 and 3, have, as common features, a housing 3 which consists of an upper section 9 concentric with a tool main axis 8, a lower section 10 deflected relative to the tool main axis 8, and an intermediate section 11 connecting the lower section 10 to the upper section 9.
  • a motor (not shown) may be arranged in the section 9 of the housing 3.
  • the motor may be of any conventional type, for example, a turbine motor, a vane motor, a Moineau type motor or an electric motor.
  • the motor rotor is connected to a rotary drill bit 13 via a universal joint and shaft leading through the intermediate section 11 and via a driven shaft 12 mounted in the lower housing section 10.
  • a stabiliser 14 is located on the lower section 10 and a stabiliser 15 is located on the upper section 9 or slightly above it.
  • the lower stabiliser 14 ensures that the axis 16 of the lower section 10, which determines the rotational axis of the driven shaft 12 and the rotary drill bit 13, intersects with the main axis 8 near to the rotary drill bit 13.
  • the point of intersection, in the embodiment of Fig. 2, is exactly at the centre of gravity of the stabiliser 14.
  • the upper stabiliser 15 ensures that the angle of deflection of the lower section 10 is maintained relative to the main axis 8, which angle is preset by the manner in which sections 10, 11 and 9 are joined together. This joining can be effected to provide a transition 17 by short pipe bends, as shown in detail in Fig. 4, between the upper section 9 and the intermediate section 11, or by inclined, threaded connections fixed directly onto sections 9, 11, as shown in Fig. 5.
  • the bore-hole 1 produced has a bent profile pointing in the direction of the axis 16. If the housing 3 is also turned, the bent rotation axis 16 also rotates, so that the resulting movement of the rotary drill bit 13 will provide a bore-hole 1 having a profile in the direction of the tool main axis 8. Selective directional drilling or straight drilling can thus be achieved in a simple manner by locking or turning the rotary table 5 and hence the drill string 4 and housing 3.
  • the bore-hole widens only slightly when operating in the straight drilling mode and compared with the directional drilling operation mode because of the eccentric movement of the rotary drill bit 13.
  • the amount of bore-hole widening corresponds to about twice the value of the axial displacement 27 between the rotational axis 16 and the main tool axis 8 in the area of the rotary drill bit 13; this axial displacement 27 is also referred to as offset.
  • the offset .27 can be reduced to zero if an eccentric stabiliser is used instead of the centric stabiliser 14 shown in Fig. 2; the eccentricity of the eccentric stabiliser is arranged to compensate for the offset.
  • Fig. 3 shows such a modified embodiment in which the stabiliser 18 adjacent to the rotary drill bit 13 is an eccentric stabiliser.
  • Such an embodiment can be used to avoid widening of the bore-hole during straight drilling and also has the advantages that wear in the gauge area of the rotary drill bit 13 and on the outer surface of the stabiliser 18 can be reduced and that bending stresses can be kept away from the housing 3.
  • the drilling tool 2 can be operated with drill bits 13 of various diameter. This is facilitated by providing interchangeable stabilisers.
  • the eccentricity of the lower stabiliser 18 can be preset. Figs. 6 to 12 illustrate various embodiments of eccentric stabiliser.
  • the stabiliser 18 shown in Figs. 6 and 7 consists in each case of a carrier body 19 and a ribbed shell 20 which is fixed on the carrier body 19 by a positive connection.
  • the ribbed shell 20 can be aligned stepwise relative to the carrier body 19.
  • the positive connections between parts 19 and 20 are formed by splines 21 and in the embodiment in Fig. 7 by radially distributed teeth 22.
  • Figs. 8 to 10 enable the ribbed shell 20 to be interchanged and provide for continuous adjustment relative to the carrier body 19.
  • the relative positions of the shell and carrier body can be fixed by frictional connection.
  • the ribbed shell 20 is fixed by an interference fit which is brought about by applying hydraulic pressure to expand the ribbed shell 20 forcing it onto the carrier body and relieving the pressure load on the ribbed shell 20.
  • the shell 20 is provided with seals 23.
  • Fig. 9 shows how the ribbed shell 20 can be fixed by means of a longitudinally slotted intermediate shell 24 which presents a conical threaded area to the ribbed shell 20 and, when screwed together with the shell 19 locks it to the carrier body 19.
  • the ribbed shell 20 is slotted along a rib and is clamped to the carrier body 19 in the manner of a clamping collar by several screws 25.
  • the stabiliser 18 is desired to have selected preset eccentricity an embodiment such as shown in Figs. 11 and 12 can be selected.
  • the stabiliser comprises an eccentric intermediate shell 26.
  • the amount of eccentricity of the stabiliser 18 can be changed stepwise between a maximum value and a minimum value, retaining the possibility of alignment of the ribbed shell 20 relative to the carrier body 19.
  • the parts are fixed by radially distributed teeth, as described with respect to the embodiment of Fig. 7.
  • the intermediate section 11 is designed as a plurality of interchangeable elements so that the angle between the axes of the upper and lower sections can be preset.
  • the embodiments are modifications of the embodiment shown in Fig. 2 and similar reference numerals are used for similar components.
  • the deflection tendency of the drilling tool is determined so that exactly the required minimum radius of curvature can be achieved during directional drilling.
  • the deflection tendency can be obtained by presetting a corresponding deflection angle a of the intermediate section 11. This is illustrated in Fig. 13 by two further angles represented by dotted lines 11' and 11", with 11" corresponding to a deflection of 0°, which is equivalenttothe intermediate section 11" being aligned coaxially with the tool main axis 8.
  • the intermediate sections are of the same length they can only differ in their angular setting a.
  • This type of set of intermediate sections is advantageous for unchanged use of the shaft which rotates inside the intermediate section 11 to drive the driven shaft 12.
  • the set of intermediate sections can differ in length and can be set at their upper and lower ends at a uniform angle a, ⁇ to the upper housing section 9 and the lower housing section 10 respectively. Sets combining both features can also be provided.
  • the length and deflection angle a of the intermediate section 11 can be fixed and the angle ⁇ can be selected to suit the desired purpose.
  • the housing section 10 is conveniently also designed as an interchangeable part in order to obtain, by interchange, various angles ⁇ or, in combination with various deflection angles a, various angles y. Also various lengths of the housing section 10 adjoining the intermediate section 11 can be employed with the connection to the intermediate section 11, for example, being made by an angularly set thread.
  • a further possibility of setting the deflection tendency of the drilling tool 2 is to change the distance between the stabilisers 14 and 15 or the distance between the stabiliser 14 and the rotary drill bit 13.
  • the first stabiliser 14 is arranged in such a way that it can be adjustably fixed in different positions on the lower housing section 10. This facility, either on its own or in combination with certain preset deflection angles and/or certain preset lengths of the intermediate section 11 or lower housing section 10, enables the deflection tendency to be controlled.
  • the stabiliser 14 may also be of variable eccentricity so that the bit offset, which changes when the stabiliser 14 is displaced on the lower housing section 10 can be compensated. As the drill bit 13 is moved further away the eccentricity of the stabiliser 14 is increased; two further positions are shown by the dotted lines at 14' and 14". To make a displacement on the housing section possible, the stabiliser 14 may, for example, be designed as shown and described in Figs. 9 and 10.
  • Fig. 15 illustrates the relationship between the arrangement of the stabilisers 14 and 15 and the rotary drill bit 13 of a drilling device as shown in Figs. 13 and 14, and the radius of curvature of the directional drilling, showing only the intersection points S 14 , S 15 and S 13 of the housing axes with the centre transverse planes of the stabilisers 14, 15 and the rotary drill bit 13 respectively.
  • the centre point of the arc of the drill hole profile achieved in this configuration is obtained by the intersection point M of the centre verticals 17; 18 on the respective connecting lines 19; 20 between the intersection points S, 4 , S 15 of the stabilisers 14 and 15 or the intersection points S 14 , S 13 of the stabiliser 14 and the tool bit 13.
  • the radius of curvature R is then obtained from the distance of the respective intersection points S 14 , S 15 and S 13 to the intersection point M of the centre verticals.
  • the connecting lines between the intersection points do not have to coincide with the axes of the respective housing sections in every embodiment.
  • values are given for a practical embodiment of the drilling tool of Fig. 14.
  • the distance between S 14 and S 15 corresponding to the length of line 19 is 8150 mm.
  • the distance between S 14 and S 13 corresponding to the length of line 20 is 1155 mm.
  • Angle y of section 11 to the tool main axis 8 is 0.6°.
  • the radius R of 435 m. is obtained.
  • the distance between S 14 and S 13 can be increased from 1155 mm. to 1955 mm. (and the distance S 14 to S, 5 can be reduced) so as to increase the deflection tendency and reduce the radius of curvature R (cf. R', M' and S' 14 in Fig. 4).

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  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Mechanical Engineering (AREA)
  • Earth Drilling (AREA)
  • Polyesters Or Polycarbonates (AREA)
  • Biological Depolymerization Polymers (AREA)
EP85105353A 1984-05-12 1985-05-02 Apparatus for optional straight or directional drilling underground formations Expired EP0163946B1 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DE19843417743 DE3417743C1 (de) 1984-05-12 1984-05-12 Vorrichtung zum wahlweisen Geradeaus- oder Richtungsbohren in unterirdische Gesteinsformationen
DE3417743 1984-05-12
DE19843423465 DE3423465C1 (de) 1984-06-26 1984-06-26 Vorrichtungen zum wahlweisen Geradeaus- oder Richtungsbohren in unterirdische Gesteinsformationen
DE3423465 1984-06-26

Publications (2)

Publication Number Publication Date
EP0163946A1 EP0163946A1 (en) 1985-12-11
EP0163946B1 true EP0163946B1 (en) 1989-04-05

Family

ID=25821161

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85105353A Expired EP0163946B1 (en) 1984-05-12 1985-05-02 Apparatus for optional straight or directional drilling underground formations

Country Status (3)

Country Link
EP (1) EP0163946B1 (no)
CA (1) CA1235686A (no)
NO (1) NO162926C (no)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9523244B2 (en) 2012-11-21 2016-12-20 Scientific Drilling International, Inc. Drill bit for a drilling apparatus

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5094304A (en) * 1990-09-24 1992-03-10 Drilex Systems, Inc. Double bend positive positioning directional drilling system
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

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB636879A (en) * 1946-07-12 1950-05-10 Rolen Arcenjevitch Joannesjan Improvements in or relating to the drilling of deep wells
US3260318A (en) * 1963-11-12 1966-07-12 Smith Ind International Inc Well drilling apparatus

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3380543A (en) * 1966-01-19 1968-04-30 Pan American Petroleum Corp Directional well-drilling apparatus
FR1593999A (no) * 1968-12-04 1970-06-01
JPS5248921B2 (no) * 1973-03-08 1977-12-13
US3938853A (en) * 1974-05-01 1976-02-17 Christensen Diamond Products Company Shrink-fit sleeve apparatus for drill strings
US3993127A (en) * 1974-08-08 1976-11-23 Viktor Gavrilovich Chepelev Apparatus for positioning a working implement in a borehole
US4059164A (en) * 1976-05-19 1977-11-22 Farris Ralph J Self-stabilizing drilling tool
US4108256A (en) * 1977-05-12 1978-08-22 Continental Oil Company Sliding stabilizer assembly
US4185704A (en) * 1978-05-03 1980-01-29 Maurer Engineering Inc. Directional drilling apparatus
BE886147A (fr) * 1980-11-13 1981-03-02 American Coldset Corp Stabilisateur de forage.

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB636879A (en) * 1946-07-12 1950-05-10 Rolen Arcenjevitch Joannesjan Improvements in or relating to the drilling of deep wells
US3260318A (en) * 1963-11-12 1966-07-12 Smith Ind International Inc Well drilling apparatus

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9523244B2 (en) 2012-11-21 2016-12-20 Scientific Drilling International, Inc. Drill bit for a drilling apparatus

Also Published As

Publication number Publication date
NO162926C (no) 1990-03-07
EP0163946A1 (en) 1985-12-11
CA1235686A (en) 1988-04-26
NO162926B (no) 1989-11-27
NO851885L (no) 1985-11-13

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