EP0170548A1 - Bohrwerkzeuge zur Erzielung einer grossen Reinigungswirkung der Angriffsfläche - Google Patents

Bohrwerkzeuge zur Erzielung einer grossen Reinigungswirkung der Angriffsfläche Download PDF

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Publication number
EP0170548A1
EP0170548A1 EP85401183A EP85401183A EP0170548A1 EP 0170548 A1 EP0170548 A1 EP 0170548A1 EP 85401183 A EP85401183 A EP 85401183A EP 85401183 A EP85401183 A EP 85401183A EP 0170548 A1 EP0170548 A1 EP 0170548A1
Authority
EP
European Patent Office
Prior art keywords
tool
axis
nozzle
central part
plane
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.)
Granted
Application number
EP85401183A
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English (en)
French (fr)
Other versions
EP0170548B1 (de
Inventor
Christian Bardin
Henri Cholet
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.)
IFP Energies Nouvelles IFPEN
Original Assignee
IFP Energies Nouvelles IFPEN
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Publication of EP0170548A1 publication Critical patent/EP0170548A1/de
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Publication of EP0170548B1 publication Critical patent/EP0170548B1/de
Expired legal-status Critical Current

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    • 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
    • E21B10/00—Drill bits
    • E21B10/60—Drill bits characterised by conduits or nozzles for drilling fluids
    • E21B10/61—Drill bits characterised by conduits or nozzles for drilling fluids characterised by the nozzle structure
    • 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
    • E21B10/00—Drill bits
    • E21B10/60—Drill bits characterised by conduits or nozzles for drilling fluids

Definitions

  • the present invention relates to an improved rotary drilling tool with high efficiency for cleaning the working face.
  • Rotary drilling tools are already known comprising a body, a first end of which is connected to rotation drive means and the second end of which defines the cutting face. Such tools are described in American patents US-A-3,645,346, US-A-4,323,130 and US-A-3,838,742 and British GB-A-2,047,308.
  • a disadvantage of the prior art lies in the fact that the distribution currently adopted for these jets is not favorable to good cleaning of the central part of the tool, which limits the performance in forward speed of the tool and increases wear.
  • the object of the present invention is to propose an improvement to the drilling tools so as to increase the performance thereof by a more efficient sweeping of the cuttings on the cutting face and more particularly in the central part, or central zone, of the tool.
  • the present invention can be applied to drilling tools or drill bits working by chip removal (blade tool) or by abrasion.
  • the first tools mentioned generally include polycrystalline synthetic diamond cutting elements, the second generally include natural diamonds.
  • This objective is obtained according to the present invention, by orienting at least one jet inclined preferentially towards the central part of the tool, the other jets not coming to interfere with this first jet.
  • speed is generally understood to mean the average speed obtained from the integration of speeds over the shortest distance separating the tool from the geological formation.
  • the jet (s) preferably oriented towards the central part of the tool must be positioned so that the vector obtained by the orthogonal projection on a plane perpendicular to the axis of the tool of the speed of flow in the central part of the tool is not zero.
  • This vector will be called the effective speed vector.
  • This or these jets preferably oriented towards the central part of the tool will advantageously be associated with one or more jets whose flow preferably moves away from the central part of the tool, this or these jets not being on the line segment passing through the axis of the tool and the starting point of a jet preferentially oriented towards the central part of the tool; this line segment mentioned above is limited by the axis of the tool and by the starting point of the jet preferentially oriented towards the central part of the tool.
  • the present invention relates to a method improving the clearance of a rotary drilling tool, in particular on itself in operation, around a proper axis, or axis of the tool.
  • This tool comprises a body, a first end of which is adapted to be connected to rotary drive means and the second of which end defines the cutting face, the area of the second end adjacent to said axis is called the central part of the tool, the tool comprises at least one nozzle.
  • the central part, or central zone of the tool is defined by the part of the tool close to the center of the tool. This center is itself defined as the intersection of the tool's own axis with the exterior surface of the tool.
  • the method according to the invention is characterized in that said disk is positioned to produce a flow oriented towards the central part of the tool, the vector obtained by the orthogonal projection on a plane perpendicular to the axis of the tool of the speed of said flow in the central part of the tool being non-zero at any point of the central part of the tool.
  • Said vector will be qualified as an effective speed vector as already mentioned above.
  • the method according to the invention can be applied to the case of a tool comprising several nozzles.
  • these nozzles are positioned and dimensioned to produce a resulting flow in the center of the tool, the effective velocity vector of which is not zero at any point in the central part of the tool.
  • the tool includes additional nozzles adapted to produce flows having a non-zero tangential velocity component, relative to a circle centered on a point belonging to the axis of l 'tool.
  • the nozzle or nozzles are positioned so that there is at least one axis, called the axis of circulation, belonging to the plane perpendicular to the axis of the tool.
  • the orthogonal projections on this axis of the different effective speed vectors of the central part of the tool are called traffic vectors.
  • all of the traffic vectors are oriented in the same direction.
  • said axis can be a curved line. But preferably, it will be a straight axis passing through the axis of the tool.
  • the present invention also relates to a drilling tool for implementing the method and these variants described above.
  • This tool is characterized in that it comprises at least a first injection nozzle positioned at a first location of the tool, said nozzle comprising an injection channel whose axis is oriented substantially towards the central zone of the tool.
  • the tool according to the invention may comprise at least one second nozzle positioned on the side of the tool opposite to that containing the first nozzle, said opposite side being defined by the portion of the tool located in the half-space delimited by a first plane passing through the axis of the tool, perpendicular to a second plane containing a point of the injection orifice of said first nozzle as well as the axis of the tool and not containing not said first nozzle, said nozzle comprising an injection channel adapted to produce a flow substantially oriented in the direction opposite to that defined by the central zone of the tool.
  • the second injection nozzle can be positioned on the tool substantially in a half-plane belonging to the second plane, this half-plane being delimited by the axis of the tool and does not contain the first nozzle .
  • the tool can comprise several fluid injection nozzles having fluid injection channels whose axis is oriented towards the central zone of the tool. These due being posi on the tool on the same side with respect to a plane passing through the axis of the tool.
  • the tool may include a third nozzle comprising a third channel, said third nozzle being positioned substantially in the vicinity of said first nozzle, the axis of said third channel being oriented substantially in the opposite direction to that of the first nozzle .
  • the reference 1 designates as a whole the body of the drilling tool or drill bit according to the invention which will, for example, made of special steel. At a first of its ends, this tool is adapted to be connected to rotary drive means, for example by means of a thread 2.
  • These drive means of the rotary tool will include a holder tool of which the drill bit is made integral, and which is part of the rotary drilling column, or which can be directly driven in rotation by the rotor of a downhole motor.
  • the second end or head 3 of the drill bit has a face delimiting the cutting face of the tool, this face comprising a plurality of means 4 for destroying the formation to be drilled.
  • the reference 5 represents the axis of the tool and the reference 6 represents the central part or central zone, of the tool which can be delimited for example by the part of the surface of the second end of the tool included inside a cylinder whose axis coincides with the axis of the tool 5 and whose diameter is equal to the outside diameter of the tool divided by three.
  • the cleaning of the cuttings and their evacuation is done by a circulation of the drilling fluid which is brought by the drill string as far as the interior cavity 7 of the drill bit.
  • the fluid is then distributed by means of a bore 16 to at least one first nozzle 9 having a fluid injection channel whose axis 17 is oriented substantially towards the central zone 6 of the tool.
  • injection nozzle means the part of the nozzle which will orient the direction of the jet, thus in FIG. 2, the channel of nozzle 18 corresponds to passage 19.
  • the axis 20 of the channel 19 of nozzle 18 can be defined as the direction resulting from the flow, or jet, produced by this channel 19.
  • the axis 20 of the channel 19 of the nozzle 18 is assumed to be oriented in the direction of the flow produced by the nozzle, this direction is indicated in FIG. 2 by the arrow 22.
  • the fluid from the nozzle 9 is discharged through the ring finger 8 (Fig. 1).
  • the drill bit 1 in FIG. 1 has a second nozzle 23 which has an axis 24 oriented towards the ring finger 8.
  • This second nozzle is located on the side of the drill bit 25 opposite to that containing the first nozzle and which bears the reference 26.
  • the so-called opposite side 25 is defined by the portion of the tool located in the half-space delimited by a first plane passing through the axis of the tool perpendicular to a second plane containing a point of the injection orifice of the first nozzle 9 and the drill bit axis and which does not contain the first nozzle 9.
  • the second plane corresponds to the plane of the figure itself.
  • the drill bit in FIG. 1 has a third nozzle 27 which can be supplied by the same bore 16 as that which supplies the first nozzle 9.
  • the axis 28 of the channel of this third nozzle 27 is oriented substantially in the direction opposite to that of the first nozzle. It should be understood by this that the third nozzle 27 has a fluid injection channel which creates a flow moving away from the plane perpendicular to the axis 17 of the first channel.
  • the third nozzle 27 can be supplied by a bore independent different from that supplying the first nozzle 9.
  • the reference 11 represents the cutting face as it is machined by the tool.
  • Reference 12 represents the plane tangent to the working face at the point of impact of the jet on the latter.
  • the reference 13 represents the plane tangent to the working face at the point closest to the nozzle from which the jet f originates.
  • the reference 14 is the projection oriented in the direction of progression of the tool from the axis of the tool 5 on the plane 13.
  • the reference 15 designates the projection of the trajectory of the jet f at the outlet of the nozzle in projection on the plane 13.
  • ⁇ is the angle formed by the projections 14 and 15.
  • the angle 6 is calculated starting from the half-line AB where A is the point of intersection of the projections 14 and 15.
  • the jets used are jets inclined with respect to the working face, so that the angle (X, formed by the jet f with the plane tangent 12 to the working face at the point of impact of this jet is different from 90 °.
  • jet oriented preferentially towards the central part of the tool is used to mean any jet originating from a nozzle external to this central part 6 and the orthogonal projection of the trajectory on a plane perpendicular to the axis 5 of the tool. is partly in the orthogonal projection on this plane of the central part 6 of the tool. Is also considered a jet preferentially oriented towards the central part of the tool any jet from a nozzle inside this central part 6 and preferentially oriented towards the center of the tool. A jet is called a jet preferentially oriented towards the central part of the tool when the angle. defined in Figure 4 has a value less than 90 °.
  • the drill bit 29 comprises a single nozzle 30 of oblong shape (FIG. 5).
  • the plane of this figure corresponds to a plane perpendicular to the axis of the tool 20.
  • the axis 38 represents the axis of circulation of the fluid.
  • the arrow 39 represents an effective velocity vector obtained by the orthogonal projection on the plane of the figure of a velocity vector of the flow in the central part of the tool 33.
  • the circle 40 represents the orthogonal projection on the plane of the figure of the limit of the central area 33.
  • the reference 41 designates the circulation vector obtained by the orthogonal projection of the effective speed vector 39 on the circulation axis 38.
  • the vector 41 of movement can be obtained by projection in a plane perpendicular to the flow axis 38, the speed of flow on the flow axis August 3.
  • the different circulation vectors of the central part of the tool are oriented in the same direction.
  • the application of the invention leads to the best efficiency when all the jets are inclined relative to the working face, but it retains its value when one or more jets are not inclined by compared to the size front.
  • the value of the angle ⁇ for an inclined jet will advantageously be less than 45 °.
  • the value of the angle 6. for a jet oriented preferentially towards the central part of the tool will advantageously be less than 45 °.
  • the jets preferably oriented towards the central part of the tool will preferably be located on the same side of a plane passing through the axis 5 of the tool in order to prevent these jets from annihilating themselves in the central part of the tool.
  • FIG. 6 shows a possible application of the present invention allowing good cleaning of the tool and the cutting face.
  • This tool comprises a nozzle 31 creating a jet 32 oriented towards the central part 33 of the tool and whose essential function is to properly clean said central part 33.
  • the nozzles 34 create jets 35 which are not oriented towards the central part of the tool 33 and whose essential function is to clean the surface of the tool in contact with the cutting face, this surface not including the central part of the tool.
  • the nozzles 34 create a centrifugal rotating flow which is particularly effective for cleaning the tool and in particular its periphery.
  • the nozzles positioned on the tool can be removable or fixed, of identical or different section.
  • the fixed nozzles can be formed by a simple channel made directly in the body of the tool and having an appropriate inclination of the injection orifice.
  • the sum of the sections of the jets oriented so preferential towards the central part of the tool will preferably be greater than or equal to one third of the total section ST of passage of the nozzles placed on the tool and preferably less than or equal to two thirds of the section ST.
  • FIG. 7 represents a diagram showing the gain brought by the invention on the capacity of the drilling tool to evacuate the cuttings which it creates at the bottom of the wellbore.
  • the ordinate axis 10 of this diagram represents the capacity of a tool to remove spoil.
  • the abscissa axis 21 represents the time during which a drilling fluid is passed through the tool.
  • the reference 36 corresponds to the performance curve of a tool according to the present invention and the reference 37 corresponds to the performance curve of a tool according to the prior art.
  • the tool is placed in a cell simulating the bottom of the wellbore. Between the tool and the cell, a given volume V of sand simulating the cuttings is introduced.
  • a fluid is circulated at a given flow rate through the tool and, as a function of time, the volume of cuttings evacuated is recorded relative to the volume of cuttings initially placed in the cell.
  • the capacity of the tool to remove the cuttings corresponds to the ratio of the volume of cuttings removed to the initial volume of cuttings V.
  • the performance curve 37 of a tool according to the prior art substantially reaches a horizontal asymptote corresponding to a removal capacity of the cuttings of the order of 80%, which means that the cuttings remaining, ie almost 20% of the initial cuttings are very difficult to remove.
  • the tool according to the present invention leaves practically no more cuttings in the cell, due in particular to good cleaning of the central part of the tool.

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  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Earth Drilling (AREA)
  • Processing Of Stones Or Stones Resemblance Materials (AREA)
EP85401183A 1984-06-27 1985-06-14 Bohrwerkzeuge zur Erzielung einer grossen Reinigungswirkung der Angriffsfläche Expired EP0170548B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8410123 1984-06-27
FR8410123A FR2566832B1 (fr) 1984-06-27 1984-06-27 Methode et perfectionnement aux outils de forage permettant une grande efficacite du nettoyage du front de taille

Publications (2)

Publication Number Publication Date
EP0170548A1 true EP0170548A1 (de) 1986-02-05
EP0170548B1 EP0170548B1 (de) 1989-04-19

Family

ID=9305497

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85401183A Expired EP0170548B1 (de) 1984-06-27 1985-06-14 Bohrwerkzeuge zur Erzielung einer grossen Reinigungswirkung der Angriffsfläche

Country Status (4)

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US (1) US4738320A (de)
EP (1) EP0170548B1 (de)
DE (1) DE3569597D1 (de)
FR (1) FR2566832B1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010070190A1 (en) * 2008-12-17 2010-06-24 Oy Atlas Copco Rotex Ab Method and apparatus for down-the-hole drilling

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4776412A (en) * 1988-01-29 1988-10-11 Reed Tool Company Nozzle assembly for rotary drill bit and method of installation
GB2252574B (en) * 1991-02-01 1995-01-18 Reed Tool Co Rotary drill bits and methods of designing such drill bits
US5203824A (en) * 1991-09-23 1993-04-20 Robert Henke Method and apparatus for preparing the surface of a region of soil for further testing
GB2277760B (en) * 1993-05-08 1996-05-29 Camco Drilling Group Ltd Improvements in or relating to rotary drill bits
US20010054989A1 (en) * 1993-10-22 2001-12-27 Matthew Zavracky Color sequential display panels
US5794725A (en) * 1996-04-12 1998-08-18 Baker Hughes Incorporated Drill bits with enhanced hydraulic flow characteristics
US6082473A (en) * 1998-05-22 2000-07-04 Dickey; Winton B. Drill bit including non-plugging nozzle and method for removing cuttings from drilling tool
EP0959224A3 (de) 1998-05-22 2000-07-12 Winton B. Dickey Düse mit seitlicher Öffnung für einen PDC Bohrkopf

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3645346A (en) * 1970-04-29 1972-02-29 Exxon Production Research Co Erosion drilling
US3838742A (en) * 1973-08-20 1974-10-01 Gulf Research Development Co Drill bit for abrasive jet drilling
GB2047308A (en) * 1979-05-02 1980-11-26 Christensen Inc Drill bit for well drilling
US4323130A (en) * 1980-06-11 1982-04-06 Strata Bit Corporation Drill bit

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2807444A (en) * 1953-08-31 1957-09-24 Hughes Tool Co Well drill
US2776115A (en) * 1953-10-29 1957-01-01 Jr Edward B Williams Drill bit
US3144087A (en) * 1961-01-05 1964-08-11 Edward B Williams Iii Drill bit with tangential jet
US3220754A (en) * 1963-08-26 1965-11-30 Christensen Diamond Prod Co Replaceable drill bit nozzles
US3746108A (en) * 1971-02-25 1973-07-17 G Hall Focus nozzle directional bit
US4296824A (en) * 1978-06-29 1981-10-27 Hughes Tool Company Nozzle placement in large diameter earth boring bits
US4546837A (en) * 1980-03-24 1985-10-15 Reed Tool Company Drill bit having angled nozzles for improved bit and well bore cleaning
US4540056A (en) * 1984-05-03 1985-09-10 Inco Limited Cutter assembly

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3645346A (en) * 1970-04-29 1972-02-29 Exxon Production Research Co Erosion drilling
US3838742A (en) * 1973-08-20 1974-10-01 Gulf Research Development Co Drill bit for abrasive jet drilling
GB2047308A (en) * 1979-05-02 1980-11-26 Christensen Inc Drill bit for well drilling
US4323130A (en) * 1980-06-11 1982-04-06 Strata Bit Corporation Drill bit

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010070190A1 (en) * 2008-12-17 2010-06-24 Oy Atlas Copco Rotex Ab Method and apparatus for down-the-hole drilling

Also Published As

Publication number Publication date
FR2566832A1 (fr) 1986-01-03
DE3569597D1 (en) 1989-05-24
FR2566832B1 (fr) 1986-11-14
US4738320A (en) 1988-04-19
EP0170548B1 (de) 1989-04-19

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