EP0184304A1 - Procédé et dispositif pour le forage de puits déviés - Google Patents
Procédé et dispositif pour le forage de puits déviés Download PDFInfo
- Publication number
- EP0184304A1 EP0184304A1 EP85307707A EP85307707A EP0184304A1 EP 0184304 A1 EP0184304 A1 EP 0184304A1 EP 85307707 A EP85307707 A EP 85307707A EP 85307707 A EP85307707 A EP 85307707A EP 0184304 A1 EP0184304 A1 EP 0184304A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- drill
- drill bit
- wellbore
- drilling
- extension sub
- 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- Withdrawn
Links
- 238000005553 drilling Methods 0.000 title claims abstract description 82
- 238000000034 method Methods 0.000 title claims description 29
- 230000000694 effects Effects 0.000 claims abstract description 6
- 239000012530 fluid Substances 0.000 claims description 9
- 230000000977 initiatory effect Effects 0.000 claims 1
- 238000005520 cutting process Methods 0.000 description 5
- 230000005484 gravity Effects 0.000 description 4
- 230000007423 decrease Effects 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000003381 stabilizer Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000004568 cement Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000000284 resting effect Effects 0.000 description 1
- 238000010079 rubber tapping Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
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
- E21B17/02—Couplings; joints
- E21B17/04—Couplings; joints between rod or the like and bit or between rod and rod or the like
- E21B17/07—Telescoping joints for varying drill string lengths; Shock absorbers
-
- 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
- E21B4/00—Drives for drilling, used in the borehole
- E21B4/20—Drives for drilling, used in the borehole combined with surface drive
-
- 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
- E21B44/00—Automatic control systems specially adapted for drilling operations, i.e. self-operating systems which function to carry out or modify a drilling operation without intervention of a human operator, e.g. computer-controlled drilling systems; Systems specially adapted for monitoring a plurality of drilling variables or conditions
- E21B44/005—Below-ground automatic control systems
-
- 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
Definitions
- the present invention relates to rotary drilling and, more particularly, to a directional drilling technique for providing deviated wellbores at significantly greater inclinations and/or over horizontal distances substantially greater than that currently being achieved by conventional directional drilling practices.
- the success of such directional drilling should benefit mainly offshore drilling projects as platform costs are a major factor in most offshore production operations.
- Wellbores with large inclination or horizontal distance offer significant potential for (1) developing offshore reservoirs not otherwise considered to be economical, (2) tapping sections of reservoirs presently considered beyond economical or technological reach, (3) accelerating production by longer intervals in the producing formation due to the high angle holes, (4) requiring fewer platforms to develop large reservoirs, (5) providing an alternative for some subsea com p letions, and (6) drilling under shipping fairways or to other areas presently unreachable.
- a drill string comprised of drill collars and drill pipe is used to advance a drill bit attached to the drill string into the earth to form the wellbore.
- the desired weight-on-bit for effective drilling from the drill string decreases as the cosine of the inclination angle, and the weight of the drill string lying against the low side of the wellbore increases as the sine of the inclination angle.
- the force resisting the movement of the drill string along the inclined wellbore is the product of the apparent coefficient of friction and the sum of the forces pressing the string against the wall.
- drill strings tend to slide into the hole from the force of gravity at inclination angles up to approximately 60°. At higher inclination angles, the drill strings will not lower from the force of gravity alone, and must be mechanically pushed or pulled, or alternatively, the coefficients of friction can be reduced.
- a method and system for drilling a deviated wellbore into the earth by rotary drilling wherein a drill string is used to advance a drill bit through the earth and a drilling fluid is circulated down the drill string and returned from the wellbore in the annulus formed about the drill string.
- a vertical first portion of the wellbore is drilled into the earth from a surface location to a kick-off point by rotating and advancing a drill string and drill bit into the earth.
- a deviated second portion is initiated at the kick-off point and is drilled by a drill tool comprised of a drill string, a drill bit, a drill motor, and an extension sub having both contracted and extended positions for providing weight to the drill bit during movement from its contracted to its extended position.
- the drill tool is positioned so that the drill bit is a predetermined distance above the wellbore bottom.
- a rapid dynamic movement downward is imparted to the drill tool so that the drill bit impacts the wellbore bottom and places the extension sub in its contracted position.
- a drilling stroke of the drill bit into the earth below the wellbore bottom is carried out by simultaneously maintaining the drill string stationary, rotating the drill bit under control of the drill motor, and advancing the drill bit under the weight provided by the extension sub in moving from its contracted position to its extended position.
- the drill tool Upon completion of the drilling stroke, the drill tool is raised so as to again position the drill bit at the predetermined distance above the wellbore bottom. A new drilling stroke is then initiated.
- the imparting of downward movement to the drill tool to place the extension sub in the contracted position includes the high-speed rotation of the drill string, in the order of 150 revolutions per minute, to take advantage of the compound coefficient of friction principle and the rapid lowering of the drill tool from a distance of about 9.15 meters (30 feet) above the wellbore bottom.
- both the drill bit'and axial movement of the extension sub in providing weight on the drill bit are angularly directed relative to the axial direction of the wellbore so as to effect a change in the direction of the wellbore.
- a desired weight-on-bit is at least 9,080 Kg (20,000 pounds) when the extension sub is stroked from its contracted position and at least 7,164 Kg (16,000 pounds) when in its fully extended position.
- the weight is under spring-loaded control.
- the weight is under hydraulic or compressed gas control.
- This invention is directed to a rotary drilling technique for drilling a deviated wellbore into the earth and, more particularly, to a method and apparatus for supplying a desired weight-on-bit for the effective drilling of the deviated wellbore.
- a drill string is employed which is comprised of drill pipe, drill collars, and a drill bit.
- the drill pipe is made up of a series of joints of seamless pipe interconnected by connectors known as tool joints.
- the drill pipe serves to transmit rotary torque and drilling mud from a drilling rig to the bit and to form a tensile member to pull the drill string from the wellbore.
- the drill pipe is always in tension during drilling operations.
- Drill pipe commonly varies from 8.9 cm (3-1/2") to 12.7 cm (5") in outside diameter.
- Drill collars are thick-walled pipe as compared to drill pipe and thus are heavier per linear foot than drill pipe.
- the drill collars act as stiff members of the drill string.
- the drill collars are normally installed in the drill string immediately above the bit and serve to supply weight on the bit.
- a drilling rig which utilizes a rotary table for applying torque to the top of the drill string to rotate the drill pipe and the drill bit.
- the rotary drill table also acts as a base stand on which all tubulars, such as drill pipe, drill collars, and casing, are suspended in the hole from the rig floor.
- a kelly is used as a top tubular member in the drill string and the kelly passes through the rotary table and is acted upon by the rotary table to apply the torque through the drill pipe to the drill bit.
- Mud pumps are used for circulating drilling fluid or mud intermediate the drilling rig and the bottom of the wellbore.
- the drilling fluid is pumped down the drill string and out through the drill bit and is returned to the surface through the annulus formed about the drill pipe.
- the drilling fluid serves such purposes as removing earth cuttings made by the drill bit from the wellbore, cooling the bit, and lubricating the drill pipe to lessen the energy required in rotation.
- casing is normally run thereinto and is cemented for the purpose of sealing and maintaining the casing in place.
- a vertical first portion of the wellbore into the earth's crust from a surface location to a kick-off point at about the lower end of the first portion by rotating and advancing a drill string and drill bit into the earth's crust.
- a deviated second portion of the wellbore is initiated at the kick-off point.
- FIG. 1 there is shown a wellbore 1 having a vertical first portion 3 that extends from the surface 5 of the earth to a kick-off point 7 and a deviated second portion 9 of the wellbore which extends from the kick-off point 7 to the wellbore bottom 11.
- a shallow or surface casing string 13 is shown in the wellbore surrounded by a cement sheath 15.
- a drill string 17, having a drill bit 19 at the lower end thereof, is shown in the wellbore 1.
- the drill string 17 is comprised of drill pipe 21 and the drill bit 19, and will normally include drill collars (not shown).
- the drill pipe 21 is comprised of joints of pipe that are interconnected together by either conventional or eccentric tool joints 25, in the vertical first portion 3 of the wellbore extending in the open hole portion thereof below the casing 13 as well as in the deviated second portion 9 of the wellbore.
- the tool joints 25 in the deviated second portion 9 of the wellbore rest on the lower side 27 of the wellbore and support the drill pipe 21 above the lower side 27 of the wellbore.
- drilling fluid (not shown) is circulated down the drill string 17, out of the drill bit 19, and returned via the annulus 29 of the wellbore to the surface 5 of the earth.
- Drill cuttings formed by the breaking of the earth by the drill bit 19 are carried by the returning drilling fluid in the annulus 29 to the surface of the earth.
- These drill cuttings tend to settle along the lower side 27 of the wellbore about the drill pipe 21.
- the eccentric tool joints 25 resting on the lower side 27 of the wellbore support the drill pipe 21 above most of these cuttings.
- the drill string 17 is rotated and the rotation of the eccentric tool joints 25 causes the drill pipe 21 to be eccentrically moved in the wellbore.
- This movement of the drill pipe 21 tends to sweep the drill cuttings (not shown) from the lower side of the wellbore 27 into the main stream of flow of the returning drilling fluid in the annulus 29, and in particular into that part of the annulus which lies around the upper side of the drill pipe 21, where they are better carried by the returning drilling fluid to the surface of the earth.
- Maintaining the desired weight on the drill bit 19 is a serious problem in drilling high-angle wellbores.
- a drill collar, laying in an 80° deviated wellbore with a zero coefficient of friction has only 17% of its weight available for pushing on the drill bit.
- a 0.2% coefficient of friction might be expected with oil mud on a sliding smooth surface.
- the drill collar will not slide from the force of gravity into the 80° wellbore and will not add any weight to the drill bit.
- the actual apparent coefficient of friction in the axial direction will most likely be greater than 0.2 with a non-rotating drill string, and, by the principle of compound coefficient of friction, be between 0.0 and 0.2 for a rotating drill string.
- FIG. 2 illustrates such apparatus in detail.
- the measuring-while-drilling sub 30 Located between the lowermost drill collar 26 and the drill bit 19 are the measuring-while-drilling sub 30, the mud motor 31 and the extension sub 32.
- Such extension sub 32 is the immediate source of weight on the drill bit 19. It can be powered by hydraulic pressure, compressed gas, mechanical springs, or the like.
- the extension sub is placed in a contracted position (i.e., compressed) by a rapid dynamic movement downward of the entire drill string 17 by such action as a high-speed rotation, a movement downward from an elevated position, or both simultaneously, until the drill bit 19 strikes the wellbore bottom.
- the drill bit 19 On commencement of drilling, the drill bit 19 is advanced or stroked under the weight from the compressed extension sub 32 while the drill string remains stationary. At the end of the drilling stroke, when the extension sub is fully extended from its contracted position at the start of the stroke, there is an end-of-stroke indication, for example, a mud pressure increase or decrease.
- the entire drill string is then drawn up the wellbore and the drill bit repositioned above the wellbore bottom. The procedure is then repeated with the drill string being lowered to compress the extension sub and the drilling stroke being thereafter again completed.
- the drill string is pulled upward until the drill bit is about 9.15 meters (30 feet) above wellbore bottom.
- the mud circulation is stopped and the drill string rotation is increased to about 150 rpm.
- a rapid lowering of the rotating drill string is then initiated to compress the extension sub 32. It is preferred that the compressed extension sub be able to advance the drill bit at least 0.61 - 1.22 m (2 to 4 feet) during each drilling stroke with no drill string advancement. This is accomplished by a soft-spring extension sub delivering 9,080 Kg (20,000 pounds) of weight to the drill bit in the compressed state and 7,164 Kg (16,000 pounds) in the extended state. Use of a compressed gas cylinder would be comparable to use of the soft spring in the extension sub.
- a hydraulic cylinder similar to the conventional hydraulic drill collar, but without the shoe reaction against the wellbore wall, could be used as the extension sub. Pump pressure would then cause the extension sub to put weight on the drill bit.
- the axial wellbore force reaction to each drilling stroke is the frictional resistance of the drill string against the wellbore wall.
- the extension sub 32 be located between the mud motor 31 and drill bit 19 as shown in FIG. 2. It could be located between the mud motor 31 and the measuring-while-drilling sub 30 or, it could be located between the measuring-while-drilling sub 30 and the lowermost drill collar 26.
- FIG. 3 illustrates diagrammatically such a change in direction of the second deviated portion 9 of the wellbore.
- the borehole follows the direction of the straight path 40 with the borehole size being shown by the dashed lines 42.
- the drill string is rotated at relatively slow speed sufficient to both maintain a straight path and to minimize friction loss from dragging of the drill string along the lower side of the wellbore.
- Such rotational speed may be in the range of 10 to 25 revolutions per minute, for example. However, slower or faster speeds may also be sufficient.
- the drill string is held stationary with the bent sub oriented as indicated by the dashed lines 43.
- the weight-on-bit is supplied by extension sub 32 such that drilling by the mud motor 31 follows the path 41 with the initial borehole size as shown by the dashed lines 44. Following such direction change, the drill string 17 is again rotated and the borehole of the size shown by dashed lines 42 continues in the new direction 41.
- the weight on the drill bit 19 would drill off immediately and bit advancement would stop without the immediate force of the extension sub 32 on the drill bit 19 since the available weight-on-bit from the drill string is generally not sufficient for high-angle wellbores.
- an alternative to the use of the bent sub 33 for angularly displacing the axis of rotation of the drill bit 19 from that of the drill string is the use of a bent housing for the drill motor 31.
- a further alternative is the offsetting of the axis of the drive shaft of the drillmotor 31.
- Another alternative is the use of non-concentric stabilizers on the drill motor 31.
- the bent sub 30 provides a deviation angle 0 of 1/4° from the vertical axis of the drill string 17 and is in the order of 1.05 m (3-1/2 feet) in length.
- a drilling offset d is provided from the center line of the wellbore as shown in FIG. 3.
- Drill bit 19 is a 30.12 cm (12-1/4 inch) bit.
- Drill motor 31 is 19.68 cm (7-3/4 inch) Delta 1000 mud motor supplied by D yna-Drill Co. of Irvine, California, and which is 7.35 m (24-1/2 feet) in length.
- the measuring-while-drilling system 30 can be of the types supplied by The Analyst/Schlumberger of Houston, Texas; Gearhart Industries of Fort Worth,Texas; Teleco Oil Field Services of Meriden, Connecticut; or Exploration Logging of Sacramento, California.
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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)
- Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
- Drilling And Boring (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US66913584A | 1984-11-07 | 1984-11-07 | |
US669135 | 1984-11-07 |
Publications (1)
Publication Number | Publication Date |
---|---|
EP0184304A1 true EP0184304A1 (fr) | 1986-06-11 |
Family
ID=24685176
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP85307707A Withdrawn EP0184304A1 (fr) | 1984-11-07 | 1985-10-25 | Procédé et dispositif pour le forage de puits déviés |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP0184304A1 (fr) |
CA (1) | CA1245212A (fr) |
NO (1) | NO854406L (fr) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4754819A (en) * | 1987-03-11 | 1988-07-05 | Mobil Oil Corporation | Method for improving cuttings transport during the rotary drilling of a wellbore |
Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
BE536490A (fr) * | 1954-03-22 | |||
GB764099A (en) * | 1954-12-10 | 1956-12-19 | Bataafsche Petroleum | Improvements in or relating to well drilling assemblies |
US2776817A (en) * | 1952-07-21 | 1957-01-08 | Shell Dev | Drilling apparatus |
US3203184A (en) * | 1963-10-15 | 1965-08-31 | Whittle | Fluid pressure motive systems, for borehole drilling |
US3497019A (en) * | 1968-02-05 | 1970-02-24 | Exxon Production Research Co | Automatic drilling system |
US3713500A (en) * | 1969-04-08 | 1973-01-30 | M Russell | Drilling devices |
US3827512A (en) * | 1973-01-22 | 1974-08-06 | Continental Oil Co | Anchoring and pressuring apparatus for a drill |
US3978930A (en) * | 1975-11-14 | 1976-09-07 | Continental Oil Company | Earth drilling mechanisms |
US4384625A (en) * | 1980-11-28 | 1983-05-24 | Mobil Oil Corporation | Reduction of the frictional coefficient in a borehole by the use of vibration |
EP0110182A2 (fr) * | 1982-11-26 | 1984-06-13 | Advanced Drilling Corporation | Dispositif pour forage profond |
US4465147A (en) * | 1982-02-02 | 1984-08-14 | Shell Oil Company | Method and means for controlling the course of a bore hole |
FR2544375A1 (fr) * | 1983-04-18 | 1984-10-19 | Alsthom Atlantique | Procede de forage avec deviation par sabot excentreur |
EP0171259A1 (fr) * | 1984-08-08 | 1986-02-12 | Mobil Oil Corporation | Méthode et dispositif pour le forage de puits déviés |
-
1985
- 1985-10-25 EP EP85307707A patent/EP0184304A1/fr not_active Withdrawn
- 1985-10-28 CA CA000493968A patent/CA1245212A/fr not_active Expired
- 1985-11-05 NO NO854406A patent/NO854406L/no unknown
Patent Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2776817A (en) * | 1952-07-21 | 1957-01-08 | Shell Dev | Drilling apparatus |
BE536490A (fr) * | 1954-03-22 | |||
GB764099A (en) * | 1954-12-10 | 1956-12-19 | Bataafsche Petroleum | Improvements in or relating to well drilling assemblies |
US3203184A (en) * | 1963-10-15 | 1965-08-31 | Whittle | Fluid pressure motive systems, for borehole drilling |
US3497019A (en) * | 1968-02-05 | 1970-02-24 | Exxon Production Research Co | Automatic drilling system |
US3713500A (en) * | 1969-04-08 | 1973-01-30 | M Russell | Drilling devices |
US3827512A (en) * | 1973-01-22 | 1974-08-06 | Continental Oil Co | Anchoring and pressuring apparatus for a drill |
US3978930A (en) * | 1975-11-14 | 1976-09-07 | Continental Oil Company | Earth drilling mechanisms |
US4384625A (en) * | 1980-11-28 | 1983-05-24 | Mobil Oil Corporation | Reduction of the frictional coefficient in a borehole by the use of vibration |
US4465147A (en) * | 1982-02-02 | 1984-08-14 | Shell Oil Company | Method and means for controlling the course of a bore hole |
EP0110182A2 (fr) * | 1982-11-26 | 1984-06-13 | Advanced Drilling Corporation | Dispositif pour forage profond |
FR2544375A1 (fr) * | 1983-04-18 | 1984-10-19 | Alsthom Atlantique | Procede de forage avec deviation par sabot excentreur |
EP0171259A1 (fr) * | 1984-08-08 | 1986-02-12 | Mobil Oil Corporation | Méthode et dispositif pour le forage de puits déviés |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4754819A (en) * | 1987-03-11 | 1988-07-05 | Mobil Oil Corporation | Method for improving cuttings transport during the rotary drilling of a wellbore |
Also Published As
Publication number | Publication date |
---|---|
CA1245212A (fr) | 1988-11-22 |
NO854406L (no) | 1986-05-09 |
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Legal Events
Date | Code | Title | Description |
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PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): BE DE FR GB IT NL |
|
17P | Request for examination filed |
Effective date: 19861106 |
|
17Q | First examination report despatched |
Effective date: 19871020 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
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18D | Application deemed to be withdrawn |
Effective date: 19890803 |
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RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: BEASLEY, ROY DENNIS Inventor name: DELLINGER, THOMAS BAYNES |