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
  • E21B25/00—Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors
  • E21B25/02—Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors the core receiver being insertable into, or removable from, the borehole without withdrawing the drilling pipe
• • 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
  • E21B10/46—Drill bits characterised by wear resisting parts, e.g. diamond inserts
  • E21B10/48—Drill bits characterised by wear resisting parts, e.g. diamond inserts the bit being of core type
• • 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
  • E21B25/00—Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors

Definitions

• the present invention relates to a core barrel, in particular in the field of oil exploration, comprising, on the one hand, at least one outer tube and a coring ring which form an outer assembly and, on the other hand, at least one tube interior which forms with a carrot possibly present inside thereof, and possibly with a part of the formations arranged under the foot of the carrot, an interior assembly, suspension and / or guide means being provided to maintain the interior assembly in exterior assembly.
• a core barrel in particular in the field of oil exploration, comprising, on the one hand, at least one outer tube and a coring ring which form an outer assembly and, on the other hand, at least one tube interior which forms with a carrot possibly present inside thereof, and possibly with a part of the formations arranged under the foot of the carrot, an interior assembly, suspension and / or guide means being provided to maintain the interior assembly in exterior assembly.
• Many corers of this kind are known.
• Their suspension and / or guide means form, between the exterior and interior assemblies, mechanical connections of the bearing type, with radial
• At least one upper mechanical connection often of the type with stop at the rear end of the inner tube, considering a direction of advance S of the core barrel in the ground, and a lower mechanical connection of the type bearing and embedding (in the crown for example) at the anterior end of the inner tube.
• the inventors of the present invention have resolutely chosen to go against the grain with respect to the practice explained above and to consider that the inner tube and the core which is housed there as the coring progresses must be relieved of the constraints which the above exterior assembly undergoes during the same coring and transmits to the interior assembly.
• the suspension and / or guide means are arranged so that the interior assembly retains at least at the location of these means, relative to the exterior assembly, a freedom of determined movement, axial and / or radial and / or angular, greater than that usual.
• the suspension and / or guide means comprise at least one rotary stop for hanging and / or supporting the inner tube in the outer tube, this stop being mounted therewith a radial clearance and / or axial and / or angular greater than the usual clearance.
• the suspension and / or guide means comprise hydrostatic bearing means in which pressurized coring fluid forms, during coring, one or more elastic cushions with radial location and / or axial and / or angular.
• means are arranged there to maintain during coring, in cooperation with the effects of the pressure of the coring fluid on the interior assembly, the latter in lift in the external assembly between the limits of said freedom of movement and / or of the aforementioned play.
• Figure 1 shows a front end of a core barrel in which the present invention can be implemented.
• Figure 2 shows the corer of Figure 1 at the location of the rear end of the inner tube and the suspension thereof in the outer tube.
• Figure 3 shows on a larger scale the location of said suspension of the inner tube in the outer tube.
• Figure 4 shows on a larger scale the anterior ends of the inner and outer tubes and the coring ring.
• FIG. 5 shows an embodiment of an intermediate guide means implementing the present invention.
• Figure 6 shows another embodiment of the suspension of the inner tube in the outer tube.
• FIG. 7 shows another variant of the means for suspending and / or guiding the inner tube in the outer tube.
• FIG. 8 shows a cross section along the plane VII-VII of FIG. 7.
• FIG. 9 shows, at the position of the rear end of the inner tube and of the suspension of the latter in the outer tube, a core barrel of the so-called “wireline” type, the anterior end of which may be similar to that shown in Figure 1.
• Figure 10 shows, in a view similar to that of Figure 9, an embodiment of a core barrel whose inner tube can not be removed from the outer tube by the technique of "wireline”.
• Figure 11 shows on a larger scale the aforementioned suspension location of Figure 10, the inner tube occupying a bearing position in the outer tube.
• Figure 12 shows on the same scale as that of Figure 11, the same place of suspension, the inner tube occupying a so-called lift position in the outer tube.
• the core barrel 1 (FIGS. 1 and 2) of the invention comprises, on the one hand, an external tube 2 and a coring ring 3 which can be considered to form an external assembly 4 and, on the other hand, at least one inner tube 5 which can be considered to form, with a core 6 possibly present inside thereof, a interior assembly 7. It can also be considered that at least part of the formations arranged under the base of the core 6 forms part of the interior assembly 7. Means 9 for hanging and / or guiding the interior assembly 7, essentially the inner tube 5, in the outer assembly 4 are provided.
• the suspension and / or guide means 9 are arranged so that the interior assembly 7 retains, at least at the location thereof, relative to the exterior assembly 4 a freedom of determined movement greater than that usual, whether axially and / or radially and / or angularly relative to the longitudinal axis of the exterior assembly 4.
• a core 6 thus broken has artificial discontinuities with respect to the core formation and therefore does not show the real nature thereof.
• a core 6 thus broken and / or damaged also presents a considerable risk, directly linked to the number of discontinuities produced, of blockage in the inner tube 5 with respect to a continuous core 6, if possible in one piece.
• the suspension and / or guide means 9 comprise (FIG. 3) at least one rotary stop 12, for example with balls, for the suspension and / or the support of the inner tube 5 in the outer tube 2.
• this stop 12 is mounted with a radial and / or axial and / or angular clearance greater than the clearance usually adjusted in the trade. To do this, the stop 12 is held, with a chosen axial clearance, - on the side of its internal diameter, between two elements 13 and 14, for example screwed together one inside the other and supporting, by a male thread 15, the inner tube 5 proper (not shown), and
• a radial clearance can also be provided between said rotary stop 12 and, on the one hand, the elements 13, 14, and, on the other hand, the clamping elements 16 and 17.
• the suspension and / or guide means 9 comprise at least one bearing 20 (FIGS. 1 and 4) and / or 21 (FIG. 5) of the radial support of the inner tube 5 in the outer assembly 4, this bearing 20, 21 being arranged so as to allow between the outer tubes 2 and inner 5 a radial clearance ( Figures 1 and 4) and / or axial ( Figures 4 and 5) and / or angular (by a combination of radial and axial clearances greater than the usually adjusted clearances).
• a radial clearance Figures 1 and 4
• Figures 4 and 5 / or axial
• angular by a combination of radial and axial clearances greater than the usually adjusted clearances.
• the bearing 21 has, for the part of the inner tube 5 which constitutes the shaft thereof, a barrel shape so as to increase a possible angular play between the axes of the inner 5 and outer 2 tubes, and therefore a flexibility of the mechanical connection at this location.
• the means 9 for suspension and / or guidance may comprise (FIG. 6) elastic means 22.
• These elastic means 22, also intended to soften the mechanical connection between the external assemblies 4 and inside 7 and to absorb a shock transmission may include rings 23 of rubber or synthetic material arranged for example above and below the rotary stop 12 mounted, for the rest, like that of FIG. 3. These rings 23 may comprise annular beads 23A intended to cooperate with grooves in the surrounding parts in order to ensure adequate reciprocal positioning of the constituent elements thus stacked.
• suspension and / or guide means 9 can comprise (FIG. 7) hydrostatic bearing means 24 in which pressurized coring fluid, arriving from the surface by a central conduit 25 and leaving by radial conduits
• FIG. 9 shows a case of a core barrel 1 of the "wireline” type, in which the inner tube 5 is suspended in the outer assembly 4 under the effect of its own weight and the pressure of the coring fluid arriving at 32 from the ground surface.
• means 33 can be arranged to maintain during coring, in cooperation with the effects of the pressure of the coring fluid pushing the inner tube 5 downward and with friction from the incoming carrot 6 in this inner tube 5, the latter in lift in the outer assembly 4 between the limits of said freedom of movement and / or the aforementioned clearance.
• the means 33 may for example comprise a set of bristles, or another coating, (not shown) arranged on the internal wall of the inner tube 5 to oppose with a known resistance at the entry of the core 6 in this tube 5.
• the means 33 may alternatively comprise means for regulating the escape of a fluid contained in the inner tube 5, arranged to thus oppose by a controlled escape a known resistance to the entry of the carrot 6 in the tube 5.
• the means 33 may comprise a combination of coring fluid passages 34, whose outlet orifices 35 open onto a peripheral surface of the interior assembly 7, and of interior surfaces 36 and 37 of the exterior assembly 4 which have diameters different.
• the fluid outlet orifices 35 occupy at rest a position, shown in Figures 9 and 1 1, in which they face an inner surface 36 apart, so as to allow a non-throttled outlet of the coring fluid.
• the inner tube 5 will tend to be pushed back by the core 6 in the opposite direction to the direction of advance S of the core, so as to no longer be pressed against a suspension shoulder 38 ( Figures 9 and 1 1) of the outer assembly 4.
• the orifices 35 occupy a position shown in Figure 12, in which they gradually face another internal surface 37 less spaced from the orifices 35, so as to gradually throttle the outlet of the coring fluid and therefore increase its pressure upstream of the orifices 35 as the interior assembly 7 rises in the exterior assembly 4.
• the interior assembly 7 comprises at the rear end of its suspension and / or guide means 9 a gripping means 39, known per se in the "wireline" technique, of the interior tube 5 for at less remove it (with a core 6) from the outer tube 2.
• the interior assembly 7 is similar to that of FIG. 9, except that it does not include gripping means 39 because, for example due to a diameter restricted interior of the outer tube 4 upstream of the inner assembly 7 (considering the direction of circulation of the coring fluid in the core barrel), the inner assembly 7 cannot be reassembled by said "wireline" technique.
• the configuration of the conduits for the passage of the coring fluid coming from location 32 and directed towards the anterior end of the corer 1 may be different from that of FIG. 9 and present for example a form of funnel .
• the pressure of this fluid at location 32 is transformed into the pushing force of the inner tube 5 in the direction S towards said anterior end of the corer 1, in the coring position, to the exclusion of any mechanical means.
• FIG. 7 shows, as a variant, that the suspension and / or guide means 9 may comprise a ball joint stop 40 to increase the flexibility of the mechanical connections between exterior 4 and interior 7 assemblies. It should be understood that the invention is in no way limited to the embodiments described and that many modifications can be made to these without departing from the scope of the present invention.
• Figure 4 shows that advantageously the crown 3 has an internal passage 41 whose diameter is greater than that which has one or more knives 42 closest to its axis of rotation and intended to determine the external diameter of the core 6 This is intended to give play at this location, so as to reduce the embedding of the core 6 in the crown 3, and therefore not to stress this core 6 by unfavorable reactions of the crown 3 during work.
• This embedding can also be reduced by reducing as much as possible the axial length of what is called the internal guard 48 (FIGS. 1 and 4) of the crown 3 (that is to say the passage provided therein. for carrot 6).
• the geometric dimensions of the suspension and / or guide means 8 are preferably optimized in particular to increase clearances between these exterior 4 and interior 7 assemblies, to reduce diameters and / or lengths (for example to reduce or avoid embedding) compared to what the skilled person has tended to do so far.
• a labyrinth seal 49 arranged on a body part 50 of the suspension means 9, below the rotary thrust ball 12 (or, if necessary, ball joint).
• the labyrinth seal 49 may consist, for example, of an annular seal 51, mounted tightly on the body part 50, and a support ring 52 which, for example, cooperates with the suspension shoulder 38 as described below. above and which comprises an annular groove in which the annular seal 51 can be housed with annular games.
• a median tube between the outer 2 and inner 5 tubes and substantially coaxial with them, may, as the case may be, be part of the exterior assembly 4 or of the interior assembly 7 .

Landscapes

• 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)
• Electromagnets (AREA)
• Processing Of Stones Or Stones Resemblance Materials (AREA)
• Joints Allowing Movement (AREA)

Applications Claiming Priority (3)

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Family Applications (1)

Country Status (7)

Cited By (1)

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• 1997
  • 1997-07-08 BE BE9700590A patent/BE1011266A3/fr not_active IP Right Cessation
• 1998
  • 1998-07-08 CA CA002295655A patent/CA2295655C/en not_active Expired - Fee Related
  • 1998-07-08 US US09/462,186 patent/US6341656B1/en not_active Expired - Lifetime
  • 1998-07-08 DE DE69822466T patent/DE69822466T2/de not_active Expired - Lifetime
  • 1998-07-08 EP EP98933379A patent/EP0995010B1/de not_active Expired - Lifetime
  • 1998-07-08 WO PCT/BE1998/000104 patent/WO1999002816A1/fr active IP Right Grant
• 2000
  • 2000-01-06 NO NO20000057A patent/NO316529B1/no not_active IP Right Cessation

Non-Patent Citations (1)

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