EP0403025B1 - Verfahren zum Bohren und Auskleiden eines Bohrlochs - Google Patents

Verfahren zum Bohren und Auskleiden eines Bohrlochs Download PDF

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Publication number
EP0403025B1
EP0403025B1 EP19900201532 EP90201532A EP0403025B1 EP 0403025 B1 EP0403025 B1 EP 0403025B1 EP 19900201532 EP19900201532 EP 19900201532 EP 90201532 A EP90201532 A EP 90201532A EP 0403025 B1 EP0403025 B1 EP 0403025B1
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EP
European Patent Office
Prior art keywords
cement
slurry
borehole
liquid
drilling
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
EP19900201532
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English (en)
French (fr)
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EP0403025A2 (de
EP0403025A3 (de
Inventor
Robert Bruce Stewart
Rudolfus Petrus Antonius Robertus Van Kleef
Wilhelmus Christianus Maria Lohbeck
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Shell Internationale Research Maatschappij BV
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Shell Internationale Research Maatschappij BV
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Publication of EP0403025A3 publication Critical patent/EP0403025A3/de
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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
    • E21B21/00—Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor
    • E21B21/12—Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor using drilling pipes with plural fluid passages, e.g. closed circulation 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
    • E21B33/00—Sealing or packing boreholes or wells
    • E21B33/10—Sealing or packing boreholes or wells in the borehole
    • E21B33/13—Methods or devices for cementing, for plugging holes, crevices or the like
    • E21B33/138—Plastering the borehole wall; Injecting into the formation

Definitions

  • the invention relates to a method of drilling and lining a borehole.
  • Applicant's co-pending British patent application No. 8814004 discloses a borehole stabilization technique wherein at the end of a drilling run a stinger is lowered into the borehole whereupon slugs of a cement slurry and drilling fluid are subsequently injected into the stinger until the cement slurry fills the annular space around the stinger and the drilling fluid fills the interior of the stinger. Subsequently the stinger is retrieved from the borehole while leaving an annular body of cement slurry and a core of drilling fluid in the borehole whereupon the cement is allowed to set to form an annular lining alongside the borehole wall.
  • Applicant has now discovered that it is possible to inject a cement slurry into the borehole already during the drilling process so that it is possible to cover the borehole wall already at an early stage with a cement slurry which is directly placed in intimate contact with the surrounding formation in the absence of the deposition during drilling of a mud cake that has to be washed away before placement of the cement lining.
  • the method according to the invention comprises the steps of drilling a borehole section while circulating a first liquid forming a drilling fluid down through a bore of a multibore drill pipe string carrying a drill bit and up through another bore of said drill pipe string while keeping a volume of a second liquid substantially stationary in an annulus between the outer circumference of the drill pipe string and the borehole wall, characterized in that said second liquid forms an over-retarded cement slurry and that the method comprises the further steps of inserting a third liquid having substantially the same density as the cement slurry into at least a lower portion of said bore and said another bore, and retrieving the bit and drill pipe string from the borehole while the third liquid flows from said bore and said another bore into the wellbore, whereafter the second liquid solidifies to an annular body of solid cement.
  • EP-A-305 834 discloses a method of creating a borehole by inserting an over-retarded cement slurry into an annular space formed between the borehole wall and a sleeve positioned in the borehole.
  • the second fluid comprises the over-retarded cement slurry whereas the first fluid comprises the drilling fluid.
  • the injected cement slurry comprises an over-retarded hydraulic cement which only hardens out under the influence of a cement solidifying agent.
  • a cement slurry comprising a hydraulic cement which is over-retarded with a glucose compound and by using a cement solidifying agent comprising calcium chloride (CaCl2) to neutralize the retarder.
  • the cement slurry may comprise a hydraulic cement which is over-retarded with a retarder that disintegrates at a critical temperature whilst the cement solidifying agent comprises chemicals which cause an exothermic reaction to raise the temperature above said critical value.
  • FIG. 1 there is shown an underground borehole 1 from which a drilling assembly comprising a multibore drill pipe string 2 and a wing type drill bit 3 is retrieved.
  • the drill pipe string 2 contains two co-axial bores 4 and 5, respectively, via which drilling fluid is circulated during the drilling process.
  • the drill bit 3 comprises a central nozzle 6 via which during drilling the drilling fluid is injected from the interior of the inner bore 4 into mud channels 7 alongside the bit face. Openings 8 are provided at the lower end of the outer drill pipe of the string 2 to allow during drilling the drilling fluid carrying drill cuttings to flow up into the outer bore 5 of the string 2.
  • the drill string 2 is equipped with thick walled drill collars 9 to create weight on bit and a series of stabilizer fins 10 are mounted on the collars 9 for keeping the bit 3 in a centralized position in the borehole 1.
  • cement slurry is injected at the top of a pipe-formation annulus 11 between the string 2 and borehole wall to form an annular body 12 of cement slurry that fills at least a lower portion of the annulus 11.
  • the stabilizer fins 10, in combination with the large diameter drill collars 9, provide a restriction against mixing of the cement slurry 12 with drilling fluid 13 during the drilling process.
  • a further restriction against contact between the drilling fluid 13 and cement slurry 12 during drilling may be provided by a sealing skirt (not shown) around the lower end of the drill collars 9 which opens if the circulation pressure of the drilling fluid exceeds a pre-set value.
  • the drilling fluid 13 circulating through the bores 4 and 5 during drilling may be any suitable fluid, such as water, oil or a foam.
  • the circulated fluid 13 may have another density than the cement slurry 14 provided that the resulting difference in hydrostatic pressure at the bottom hole is compensated by the circulating pressure of the drilling fluid.
  • the bores 4 and 5 are filled with a weighted, preferably bentonitic, liquid that has about the same density as the cement slurry column in the annulus 11. In this way it is ensured that no gravity segregation of the cement slurry will take place after retrieval of the drilling assembly.
  • a weighted, preferably bentonitic, liquid that has about the same density as the cement slurry column in the annulus 11.
  • the cement slurry contains an over-retarded hydraulic cement, such as Portland cement or an epoxy or polymeric resin, and e.g. chopped reinforcement fibres or additives such as latex polymers and epoxies to optimize the elastic properties of the cement.
  • an over-retarded hydraulic cement such as Portland cement or an epoxy or polymeric resin
  • chopped reinforcement fibres or additives such as latex polymers and epoxies to optimize the elastic properties of the cement.
  • the composition of the cement slurry 12 is selected such that the grooves that are pulled through the slurry column during retrieval of the drilling assembly by the stabilizer fins 10 and the wings of the bit 3 flatten out before the cement starts to set.
  • the cement slurry is over-retarded with a retarding additive which prevents setting of the cement during the drilling process.
  • a retarding additive which prevents setting of the cement during the drilling process.
  • a bentonitic liquid containing a cement solidifying agent which induces the cement to set as soon as the drilling assembly has been retrieved from the borehole.
  • the bores 4 and 5 of the drilling assembly may be filled with an over-retarded cement slurry as well. If in that case the drilling assembly is retrieved from the borehole at least a lower portion of the hole is entirely filled with the over-retarded cement slurry, whereupon a mud core can be spotted in the centre of the borehole by a stinger as illustrated in Figure 2.
  • the stinger 20 may be lowered into the borehole 1 after retrieval of the drilling assembly for creating an accurately centralized mud core 13 in the cement slurry 12 and for adding a cement solidifying agent.
  • Accurate centralization of the stinger 20 may be accomplished by centralizing the lower end of the stinger 20 with a series of bow spring centralizer blades 21.
  • the stinger may be equipped with a mixing sub (not shown) known from Applicants' co-pending patent application No. 8814004 via which the cement solidifying agent is mixed with the cement slurry.
  • cement solidifying agent instead of mixing the cement solidifying agent with the cement slurry at a downhole location it may also be mixed with the cement slurry at the surface by circulating the slurry up to the surface where the solidifying agent, and possibly other substances, are added and then circulating the slurry down into the annulus around the stinger whereupon the interior of the stinger is filled with mud and the mud core is spotted in the cement slurry by retrieving the stinger from the borehole as shown in Figure 2.
  • the cement solidifying agent may consist of calcium chloride (CaCl2) if the cement slurry is over-retarded with a glucose compound. After injecting the calcium chloride into the borehole via the stinger it will neutralize the glucose compound and the cement starts to set.
  • CaCl2 calcium chloride
  • the cement slurry 12 may be over-retarded with a retarder which disintegrates at a critical temperature
  • the cement solidifying agent may comprise chemicals which cause an exothermic reaction to raise the temperature of the cement slurry 12 above said critical value.
  • an electric or other heat source may be mounted on the lower end of the stinger to raise the temperature of the slurry 12 to said critical value.
  • stinger 20 is optional.
  • the use of the stinger is useful if a drill bit 3 has to be used without a central nozzle.
  • Figure 3 shows how after setting of the cement slurry to a solid annular lining 30 alongside the borehole wall the borehole 1 may be deepened by a drilling assembly comprising a multibore drill pipe string 32 and a small diameter bit 33.
  • the bit 33 is also used for milling the mud core 13 spotted by the stinger shown in Figure 2 to a desired minimum diameter. During the milling operations the mud core 13 guides the bit 33 such that it is centralized in the hole 1.
  • the drilling assembly of Figure 3 is equipped with a smaller diameter bit 33, stabilizer fins 34 and drill collars 35 than the assembly of Figure 1, whereas the drill string may consist of the same multibore drill string as shown in Figure 1.
  • a drilling fluid is circulated down via an internal bore 36 of the drill pipe string 32 to a central nozzle 37 of the bit 33, from where the fluid is circulated up via openings 38 in the drill pipe string 32 into the outer bore 39 of said string 32 as indicated by the arrows I and II.
  • the drill string 32 may be rotated as illustrated by arrow III or the string 32 may be kept stationary if the drill bit is driven by a downhole drilling motor (not shown).
  • annular space 40 between the drill string 32 and the inner surface of the cement lining 30 may be completely filled with a fresh cement slurry, but if desired only the annular space 40B between the drill string and the wall 41 of the borehole extension protruding below the cement lining 30 may be filled with cement slurry.
  • the annular body of the cement slurry may be allowed to set and may be subsequently milled out again to a proper diameter in the same manner as described with reference to Figures 1-3, namely by using an over-retarded hydraulic cement for the slurry and by filling at the end of a drilling run the bores 36 and 39 of the multibore drill string 32 either with a bentonitic liquid having about the same density as the cement slurry or with the cement slurry itself. In the latter case a mud core is spotted by a stinger in the manner described with reference to Figure 2, whereupon the annular body of cement is allowed to set.

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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)
  • Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)
  • Earth Drilling (AREA)

Claims (11)

  1. Eine Methode des Bohrens und Auskleidens eines Bohrlochs in einer Erdformation, wobei die Methode einschließt die Schritte des Bohrens eines Bohrlochabschnitts, während eine erste Flüssigkeit (13), die eine Bohrflüssigkeit darstellt, in Abwärtsrichtung durch ein Bohrrohr (4) eines Mehrfachbohrrohrstranges (2), welcher eine Bohrerspitze (3) trägt, und in Aufwärtsrichtung durch ein anderes Bohrrohr (5) des erwähnten Bohrrohrstranges (2) hindurchfließt, umfaßt, wobei ein Volumen einer zweiten Flüssigkeit weitgehend stationär in einem Ringraum (11) zwischen dem äußeren Umfang des Bohrrohrstranges (2) und der Bohrlochwand gehalten wird, dadurch gekennzeichnet, daß die erwähnte zweite Flüssigkeit eine Schlämme eines Zements (12) mit sehr stark verzögerter Abbindefähigkeit darstellt, und daß die Methode die weiteren Schritte des Einführens einer dritten Flüssigkeit, die weitgehend dieselbe Dichte wie die Zementschlämme aufweist, in mindestens einen tieferen Abschnitt des erwähnten Bohrrohres (4) und des erwähnten anderen Bohrrohres (5) in das Bohrloch einschließt, wobei sich danach die zweite Flüssigkeit zu einem ringförmigen Körper (30) von festem Zement verfestigt.
  2. Die Methode des Anspruchs 1, wobei vor der Entfernung der Bohrerspitze (3) und des Bohrrohrstranges (2) aus dem Bohrloch mindestens ein unterer Abschnitt der Bohrrohre (4, 5) mit der Schlämme (12) eines Zements mit sehr stark verzögerter Abbindefähigkeit (12) gefülllt wird und nach der Entfernung der Bohrerspitze (3) und des Bohrrohrstranges (2) aus dem Bohrloch ein Hohlstab (20) bis auf den Fuß des Bohrlochs abgesenkt wird, woraufhin der Hohlstab (20) vollständig mit der dritten Flüssigkeit gefüllt wird, welche etwa dieselbe Dichte wie die Zementschlämme (12) aufweist, und der Hohlstab (20) anschließend durch das Bohrloch hindurch angehoben wird, während sein unteres Ende im Bohrloch zentriert wird und dabei einen flüssigen Kern koaxial innerhalb des ringförmigen Körpers aus Zementschlämme (12) einbringt.
  3. Die Methode des Anspruchs 1, wobei die dritte Flüssigkeit ein Zementabbindemittel enthält, welch dritte Flüssigkeit am Ende eines Bohrvorganges durch wenigstens eines der Bohrrohre (4, 5) des Bohrrohrstranges (2) hindurchgeleitet wird, woraufhin die Bohrerspitze (3) und der Bohrrohrstrang (2) aus dem Bohrloch entfernt werden, wobei ein Kern aus Flüssigkeit, umgeben von einer ringförmigen Säule aus Zement (12), am Ende des Bohrvorganges im Bohrloch zurückbleibt.
  4. Die Methode irgendeines der vorhergehenden Ansprüche, wobei die dritte Flüssigkeit eine beschwerte, bentonithaltige Flüssigkeit ist.
  5. Die Methode irgendeines der Ansprüche 1 bis 4, wobei zumindest ein Teil des Volumens der Zementschlämme (12) in den Ringraum (11) durch Einspritzen einer Teilmenge der Zementschlämme (12) in Abwärtsrichtung durch mindestens eines der Bohrrohre (4, 5) des Bohrrohrstranges (2) und in Aufwärtsrichtung durch den Ringraum (11) in diesen eingebracht wird.
  6. Die Methode irgendeines der Ansprüche 1 bis 4, wobei mindestens ein Teil des Volumens der Zementschlämme (12) in den Ringraum (11) durch Einspritzen der Schlämme (12) am Kopf des Ringraumes (11) und Zirkulierenlassen der eingespritzten Schlämme (12) in Abwärtsrichtung durch den Ringraum (11), um mindestens einen unteren Abschnitt des Ringraumes (11) vollständig mit der Schlämme (12) zu füllen, eingebracht wird.
  7. Die Methode der Ansprüche 5 und 6, wobei ein Teil des Volumens der Zementschlämme (12) in den Ringraum (11) durch Einspritzen einer Anteilsmenge der Schlämme (12) während einer Unterbrechung des Bohrverfahrens in Abwärtsrichtung durch mindestens eines der Bohrrohre (4, 5) des Bohrrohrstranges (2) und in Aufwärtsrichtung durch den Ringraum (11), eingebracht wird, während ein anderer Teil der Schlämme (12) durch Einspritzen der Schlämme während des Bohrverfahrens am Kopfende des Ringraums (11) eingebracht wird.
  8. Die Methode irgendeines der vorhergehenden Ansprüche, wobei die eingespritzte Zementschlämme (12) einen hydraulischen Zement mit stark verzögerter Abbindefähigkeit einschließt, welcher nur unter dem Einfluß eines Zementabbindemittels aushärtet.
  9. Die Methode von Anspruch 8, wobei die eingespritzte Zementschlämme (12) einen hydraulischen Zement einschließt, dessen Abbindefähigkeit mit einer Glukoseverbindung verzögert worden ist, und das Zementabbindemittel Calciumchlorid einschließt, um den Verzögerer zu neutralisieren.
  10. Die Methode von Anspruch 8, wobei die Zementschlämme (12) einen hydraulischen Zement einschließt, dessen Abbindefähigkeit durch einen Verzögerer stark verzögert worden ist, welcher sich bei einer kritischen Temperatur zersetzt, und das Zementabbindemittel Chemikalien einschließt, die eine exotherme Reaktion verursachen, um die Temperatur über den erwähnten, kritischen Wert hinaus anzuheben.
  11. Die Methode irgendeines der Ansprüche 5 bis 7, wobei das Zementabbindemittel zu der Zementschlämme (12) durch Zirkulieren der Schlämme bis an die Erdoberfläche hinzugefügt wird, wo das Mittel in die Schlämme (12) eingespritzt wird, woraufhin man die das Mittel enthaltende Schlämme (12) erneut in das Bohrloch zirkulieren läßt und sie längs der Bohrlochwand zu einer festen Auskleidung (30) abbinden läßt.
EP19900201532 1989-06-14 1990-06-13 Verfahren zum Bohren und Auskleiden eines Bohrlochs Expired - Lifetime EP0403025B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8913647 1989-06-14
GB898913647A GB8913647D0 (en) 1989-06-14 1989-06-14 Method of drilling and lining a borehole

Publications (3)

Publication Number Publication Date
EP0403025A2 EP0403025A2 (de) 1990-12-19
EP0403025A3 EP0403025A3 (de) 1991-05-29
EP0403025B1 true EP0403025B1 (de) 1994-08-31

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EP19900201532 Expired - Lifetime EP0403025B1 (de) 1989-06-14 1990-06-13 Verfahren zum Bohren und Auskleiden eines Bohrlochs

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EP (1) EP0403025B1 (de)
CA (1) CA2018754C (de)
DE (1) DE69011972T2 (de)
GB (1) GB8913647D0 (de)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4227724A1 (de) * 1992-08-21 1994-02-24 Preussag Anlagenbau Verfahren zum Teufen und Abdichten einer Sprengbohrung
EP0777018A1 (de) * 1995-12-01 1997-06-04 Per Aarsleff A/S Vorrichtung und Verfahren zur Herstellung eines Betonschachtes im Boden und ein derart hergestellter Betonschacht
GB2357305B (en) * 1999-12-13 2002-02-13 George Stenhouse Lining bores, such as wells and pipelines
US6481501B2 (en) 2000-12-19 2002-11-19 Intevep, S.A. Method and apparatus for drilling and completing a well
AU2004265583B2 (en) 2003-07-25 2009-06-04 Exxonmobil Upstream Research Company Continuous monobore liquid lining system
DE102013005858B3 (de) 2013-04-08 2014-08-21 Schwindt Hydraulik Gmbh Verfahren zur Auskleidung von Bohrlöchern für Tiefbohrungen sowie Vorrichtung zur Durchführung des Verfahrens
WO2017108820A1 (en) * 2015-12-23 2017-06-29 Shell Internationale Research Maatschappij B.V. Configuring a velocity string in a production tubing of a wet gas production well
CN112065320B (zh) * 2020-09-30 2022-10-14 长江岩土工程有限公司 采用水泥土浆进行工程钻孔封堵方法

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4519452A (en) * 1984-05-31 1985-05-28 Exxon Production Research Co. Method of drilling and cementing a well using a drilling fluid convertible in place into a settable cement slurry
GB8531627D0 (en) * 1985-12-23 1986-02-05 Shell Int Research Drilling borehole
GB8531866D0 (en) * 1985-12-30 1986-02-05 Shell Int Research Forming impermeable coating on borehole wall
DE3729560A1 (de) * 1987-09-04 1989-03-16 Mts Minitunnelsysteme Gmbh Verfahren und vorrichtung zur herstellung einer rohrleitung in einer im erdreich ausgebildeten durchbohrung
GB8814004D0 (en) * 1988-06-14 1988-07-20 Shell Int Research Method & apparatus for placing cement lining in borehole

Also Published As

Publication number Publication date
DE69011972T2 (de) 1995-02-16
CA2018754C (en) 2004-03-02
DE69011972D1 (de) 1994-10-06
EP0403025A2 (de) 1990-12-19
EP0403025A3 (de) 1991-05-29
CA2018754A1 (en) 1990-12-14
GB8913647D0 (en) 1989-08-02

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