DE19745947B4 - Apparatus and method for drilling earth formations - Google Patents

Abstract

contraption for drilling earth formations, with a longitudinal bore limiting drill body, the connectable at its upper end with a drill string and at its bottom end is provided with a core bit, and instrumentation, by means of which well data simultaneously with the drilling of a core are receivable, characterized in that of the instrumentation at least a region within the tubular body between its outside and the longitudinal bore is arranged and from the instrumentation equipment as well data ground information parameters are receivable and the instrumentation at least one sensor for detecting at least one formation feature from the Set of characteristics well temperature, borehole pressure, formation resistance, Formation gamma radiation, nuclear magnetic resonance, density and porosity.

Description

The The invention relates to a device for drilling earth formations in an embodiment according to the preamble of claim 1 and to methods for drilling earth formations.

Especially The invention relates to a combination system of core drilling and the normal pipe by means of a using a rope string Kernbohrinnenrohreinheit pulled out of the drill string and a closure unit for forward drilling, the latter optionally with measuring equipment equipped to evaluate wellbore parameters. specially the system offers the possibility at the same time a formation in which a core drilling is carried out, as well as the kernel sample drilled from the formation to record data.

Core drilling with a rope string has been known for many years. The basic concept here is to use a core tube with an outer tube unit, which is arranged at the end of the drill string and has a core bit at its lower end. An inner tube unit for receiving a core drilled by the core bit is detachably locked in the outer tube unit. This configuration allows placement of the inner tube unit in the outer tube unit by means of a cable harness, by means of gravity or a hydraulic flow and their recovery from the outer tube unit by means of the cable strand. Examples of such rope core drilling systems are in the publications US 3,127,943 and US 5 020 612 described.

One Problem with many prior art systems is the need to the existence special drill string used with an enlarged diameter must become, to let in and retrieve to allow the inner tube unit for drilling relatively large cores over 5 cm (2 '') diameter used becomes.

Although Core drilling systems, the small or slim cores of about 4.5 cm (1 3/4 '') diameter or less boring, are known, of course, such Cores are very fragile, so that the conventional core drilling systems in the length such nuclei are reasonably limited, without breaking, can be drilled. These restriction seems primarily due to the instability of the entire core tube to be, by lateral and vertical drill bit movements in the borehole that generate vibrations. A major phenomenon, that from such drill bit movements and vibrations is the so-called Bohrkronenschleudern, although a vibration without spin also harmful is. The phenomenon of the Bohrkronenschleuderns manifests itself in drill bits with unbalanced lateral forces of the cutting members, which Forces to do so to lead, that the Drill bit rotates or hurls around a midpoint in the borehole, which is offset from the geometric center of the drill bit, so, that the Crown tends to backwards in the borehole too fling. It was observed that the spin phenomenon was due to the presence of calibration or trim cutters in certain places in the outer calibration area the drill bit reinforced is, with such cutting members also generate frictional forces during drilling. The Slingshot is a dynamic independent phenomenon and affects many make to a high degree destroying the cutting members of the drill bit off. The spin phenomenon is generated while a spiral shape of the borehole during drilling, which at Core bits leads to a non-cylindrical, spiral core, the even more sensitive fractures is and jammed easily in the inner core tube.

in view of relatively small Free rooms between the core and the pilot shoe, the core catcher and the inner tube components of the inner tube slight lateral and vertical movements of the core tube easily to a break of small diameter cores with one of them resulting nuclear blockage and destruction of the core sample. As a result Of these, small-diameter core tubes become common due to their length short core samples (eg, about 3 to 4 m (10 to 13 feet)), the without core failure, blockage and destruction can be limited. It Attempts have been made to obtain longer cores, of about 8 m (26 Foot) However, the devices used have problems due to the above-mentioned problems not led to success.

It has been recognized that certain improvements in drill bit formation, including, but not limited to, the so-called spin-free drill bits with polycrystalline diamond compact (PDC) cutters, initiated by Amoco and improved by the applicant, can be transferred to core bits to increase the safety of a core drilling operation and the quality of the cores. Patents describing spin-free drill bits are, for example, the U.S. Patent 4,982,802 . 5 010 789 . 5 042 596 . 5 099 934 . 5 109 935 . 5,111,892 . 5 119 892 . 5 131 478 . 5 165 494 and 5 178 222 , The SPE (Society of Petroleum Engineers) paper no. 24587 of LA Sinor et al. Of the Amoco Production Co. entitled "Development of an Anti-Whirl-Core Bit" discusses improvements and potential improvements in core drilling capabilities that are believed to be due the use of spin-free core bits result.

Other approaches to drill bit stabilization have been made by Amoco et al. One suggestion is to try to balance a drill bit perfectly, as in the U.S. Patent 4,815,342 is described. Another solution is to mechanically lock the projections on the bit surface in circular grooves which are cut by the cutting members on the surface, as shown in FIG U.S. Patent No. 5,090,492 is described.

All the above developments in drill bit stabilization have focused on individual elements of the drilling process, either drilling a full diameter borehole or on the core drilling.

In front a few years ago was by the Eastman Christensen Company, a predecessor applicant, a combination of a full bore and core drilling system with the option developed between solid drilling and core drilling. This system enabled alternately core drilling and full drilling operations, without the drill string too pull. In this system, both the inner tube unit were for core drilling as well as a substitute middle closure unit with a Brechfuß and cutting members for converting the coring bit into a solid drill bit over a Cable harness used and recoverable, the inner tube unit could So again to the earth's surface be transported back. This combination system used core bits with natural Diamonds and was successful for several reasons only in rare cases. At first, it was the maximum core length, which could be drilled all at once, only about 4m (13ft), which an extraordinary short interval for analysis without multiple inserts of the inner tube unit meant and a combination with special lengths of pipes for drilling down of the Mitnehmergestänges to the turntable like a pipe connection required. Additionally brought the emergence of more accurate electrical logging and analysis techniques for Data collection a reduction in the need for core analysis. Finally accepted the industry does not use the cores of relatively small diameter (5 cm) that the system provided for insertion and retrieval the inner tube unit and the middle shutter unit required standard tube parts.

In younger However, there is still time for development and industrial acceptance Hole and rotary core drilling techniques, that lead to, that cores of about 2.5 cm (1 inch) in diameter to be drilled out of the borehole can, as well as the increased use of small diameter boreholes for experimental or research drilling the former Resistance to access small diameter cores fixed. These changes in industrial practice have a renewed interest in Core drilling performed, however, so far the known core drilling systems have no possibility for a system for full bore and core drilling with a small diameter, the original, undamaged Cores of wanted Length (z. B. about 9 m (30 feet)) while avoiding nuclear blockages can cut and also the possibility offers to continue drilling between the intervals of core drilling, without pulling the drill string. Besides, no core drilling system offers the state of the art, the performance options and operating characteristics, how they can be achieved with PDC drill bits.

Another disadvantage of the known core drilling systems is the tendency for core core drilling and hole parameter evaluation to be treated as separate peripherally related operations rather than interlinked segments of an overall formation evaluation process. Although the U.S. Patent 4,955,438 While Applicant describes taking measurements of the wellbore features during a core drilling operation and physically retrieving such data from the coring apparatus by wireline or mud pulse telemetry, the presence of any such system for use in oil and gas exploration wells is not known.

From the Scriptures GB 2 293 395 It is known to make a drill body so that it either has an opening for receiving a core hole or in the Publ opening a closure is used, so that no core hole is possible. The closure is provided with measuring devices so that measurements can be made with the drill body during normal drilling.

Moreover, from the Scriptures DE 38 13 508 C1 is known to provide a drill body for receiving a core bore at its end with a measuring device to examine the material drilled. However, the drill body is only usable for core drilling, and the feasible measurements lead to limited measurement results, since the measuring device is attached to the back of the drill body.

Of the The invention is primarily based on the object, a device to create for drilling earth formations, with which it is possible, at the same time drilling down a core to record downhole data.

This object is achieved for a generic device according to claim 1 of the invention with the characterizing features of claim 1. Regarding further Ausgestaltun Gen is referred to the claims 2 to 16.

in the With regard to the generic method the object is achieved by the characterizing features of claims 17 and 18 solved.

The The invention also aims to provide a simple method for drilling an earth formation with the possibility of receiving Borehole data and triggers this object in the method forms according to claims 20 to 22.

The Invention offers the possibility alternately perform a core drilling and a full drilling, without to pull the drill string, taking out elongated cores of small diameter can be. The core tube according to the invention comprises an outer tube unit with a core bit, preferably PDC core bit, on, at the lower end of the outer tube unit is appropriate. Located immediately above the core bit itself a bearing arrangement for the drill bit end in the core tube, which alternately the end of a Inner tube unit or a middle shutter unit receives. A detent coupling is mounted on top of the inside of the outer tube unit. The inner tube unit has a catch coupling member at the upper end on, including a locking unit for engagement with the detent coupling of the outer tube and a storage unit under the lock unit for enabling a rotation between the outer tube unit and the inner tube. The lower end of the inner tube unit, with the drill bit bearing unit is engaged, has a conventional core catcher on.

The preferred PDC core bit according to the invention preferably has a spin-free design, although other stabilized drill bit designs, as discussed above are also suitable. The usage a spin-free core bit in the invention leads to the proven ability, cores of at least about 9 meters (30 feet) of high quality and with greatly increased To cut and pull recovery rate. It also offers the use a PDC core bit with optional middle shutter a penetration rate similar to that of PDC drill bits and weight-on-crown, rotational speed and hydraulic flow rates similar to those of PDC drill bits. Consequently can size Quantities of high-quality cores are obtained cost-effectively, and the total penetration rate during the Drilling is in comparison with drilling without core removal not significantly reduced, so that the operator benefits Time and cost savings as well as from those through the high quality Cores available draws stationary information.

The Use of the storage unit for the drill bit end provides a precise alignment of the inner tube for receiving the core being drilled and a seat for the lower end of the middle shutter unit, which is a plurality of cutting members, preferably PDC cutting members, and flushing liquid flushing outlets.

One optional but significant feature of the present invention is the arrangement of a suitable measuring tool, such as a gamma ray or direction measuring tool, in the middle closure unit to enable a borehole data recording during one full drilling operation. The data can be stored in the measuring tool during drilling and periodically by cable transfer or if the middle closure unit to the surface retrieved will be recorded. It may also be a drilling fluid pulse or other suitable communication system as part of the middle closure unit be grown to allow a real-time transmission of data. One or more measurement options can in the measuring tool or the instrumentation be included, such opportunities a Pressure and temperature measurement in addition to the others mentioned above Can include measurements, without being limited thereto to be. It is also advantageous that the measuring tool sensors and in particular the sensors for detecting formation features immediately adjacent to the lower or leading end of the middle closure unit, literally in the neck of the core bit, can be arranged to a very close proximity to the drill bit face and to get to the drilled formation.

It is further provided that sensors for measuring directional parameters as well as the above-mentioned borehole parameters and also other parameters such as (by way of example only) formation resistance and nuclear magnetic resonance, as well as a power supply, a data processing and storage unit and a borehole data transmission or telemetry option into one or more coring pipe units, into the wall of the Core tube between the outside and the longitudinal bore or above the core tube in a separate pipe section or casing with an axial bore aligned with the bore of the core tube, can be installed. Sensors for measuring drilling parameters such as (again only as an example) torque, rotational speed, weight on the drill bit, Vibration and borehole pressure can also in one or more components of the device, preferably be installed near the drill bit, such as in the wall of the core tube.

One Another aspect of the invention provides a simultaneous or at least concurrent measurement of borehole parameters of the formation outside the core tube before, during the same or another borehole parameter of the boring Kerns measured when entering the core inner tube unit becomes. For example, you can Gamma ray, resistance, density, porosity, sound and / or measurements nuclear magnetic resonance. It is advantageous such measurements for comparison purposes with regard to the properties make that from the outer formation be presented, in contrast to those of the core under the more controlled environment of the core tube interior and in an extremely narrow range. It is also desirable such nuclear measurements immediately after the core passage through the Neck of the core bit, if the core in his most original State and it is least likely that he is going through lavage fluid too contaminated or has lost its physical integrity. Furthermore, it is provided that the Alignment of the core is determined, both in an absolute sense as well as with respect to the environmental formation from which he cut out using the directional instrumentation of the device becomes.

Besides that is provided that a Shortstep radio telemetry system can be used to send data over one short distance from a location in the core tube wall to the inner tube unit or vice versa; this for a subsequent retransfer by a remote telemetry system in another component of the device or from one of these points to a remote telemetry module located in short distance above the core tube is arranged in the borehole. The data can retransmitted be through drilling fluid pulse, acoustic or electromagnetic telemetry or by a to surface running rope strand. Furthermore, data in an electronic Memory stored in the inner tube unit or the mentioned above middle closure unit is arranged and physically to the surface rather than a transmission retrieved in essentially real time can be. Of course data are preferably stored in an inner tube unit, middle closure unit, stored in a core tube or separate housing associated with the core drilling apparatus is, even during a transmission to the surface in real time to data loss due to poor transfer or a transmitter failure.

Of the Method aspect of the invention comprises a method of drilling, with the same directional, formation and optionally Bohrparameterdaten taken before a core drilling operation is undertaken, around a zone or layer of potential interest, such as a hydrocarbon-producing zone, to locate before the inner tube unit for receiving the core drilling commissioned becomes. In the same way it is provided that by the inclusion of such Data during the core drilling operation the operator the opportunity the determination of when to finish the core drilling, so that not Core samples in a rock substantially over a zone of potential Interest to be taken out. In the practice of this Aspect of the invention, it is of course desirable, the recorded Data to the surface to transmit on a real-time basis especially when drilling in a potential production zone.

At the Core drilling can be enough data for each core drilled section or for to take each core-drilled interval at the time when brought the inner tube unit with the core sample contained therein to the surface becomes; however, it is obviously preferable to the termination point the zone of interest as exactly as possible to locate what means that one Real-time data transmission can also be beneficial in this situation.

Further Features and advantages of the invention will become apparent from the following Description in conjunction with the drawing, in which several embodiments a drilling device according to the invention are illustrated schematically. In the drawing show:

1 a longitudinal section through a core tube according to the invention,

2 an enlarged longitudinal section through the lower end of the core tube according to the invention, wherein an inner tube unit is in its position for core drilling,

3 an enlarged longitudinal section through the lower end of the core tube according to the invention, wherein a middle closure device is in its position for drilling,

4 a view of the drill bit showing the Schneidgliedplazierung looking down through the Bohrkronenfläche,

5 an enlarged vertical section through an embodiment of a Innenmaßschneideinrichtung a drill bit with a low penetration angle and cooperating core shoe means,

6 FIG. 4 is a longitudinal section through a preferred embodiment of a core drilling apparatus with an inner tube unit in an embodiment for simultaneous core drilling and recording of borehole parameters and transfer of the obtained borehole data to the surface of the earth, FIG.

7 to 9 each a further embodiment of a coring device according to representations 6 and

10 a representation of the lower end of a preferred instrumented middle closure device according to the invention in longitudinal section.

As it turned out first 1 results, a core tube protrudes 10 down into a borehole 12 from a drill collar 14 at the lower end of a drillstring extending to the surface.

The core tube 10 includes an outer tube unit 16 with an outer tube 18 , at the upper end there is a threaded sleeve connection 20 for fastening the core tube 10 on a threaded bolt 22 the drill collar 14 located. At the bottom of the outer tube 18 is a PDC core bit 24 in an anti-spill or the like stabilized design, as described above, attached. PDC cutters 26 on the core bit 24 cutting the formation while turning the drill string, being also a core 28 is cut out of the drilled formation. The core 28 extends up into the neck 30 the core bit 24 while driving the drill bit into the formation. Possibly. can the drill bit 24 a version with a weak penetration profile according to U.S. Patent 4,981,183 have the applicant. On the inside of the outer tube 18 There is a detent coupling 32 and including a plurality of axially spaced groups of support ribs 34 extending circumferentially around the inside of the outer tube 18 herumerstrecken. Inside the core bit 24 there is a rotary bearing unit 36 for the drill bit end. Fluid channels 38 extend from the core of the drill bit to the drill bit face.

An inner tube unit 40 is in the core tube 10 shown as it is in a core drilling the case. The inner tube unit 40 comprises at its lower end a in the storage unit 36 absorbed inner tube 42 , The inner tube 42 extends upwards inside the outer tube 18 through the groups of support ribs 34 providing a support against bending the inner tube 42 Offer. At the upper end of the inner tube 42 there is an inner tube storage unit 44 which causes a rotation of the upper and lower portions of the inner tube 40 allows each other and thus, in conjunction with the storage unit 36 for the inner bit end creates the possibility that the outer tube unit 16 turns while the inner tube unit 40 remains stationary. Above the storage unit 44 is a locking unit 46 in releasable engagement with the locking coupling 32 on the inside of the outer tube 18 , At the upper end of the inner tube unit 40 is a catch coupling 50 arranged for a selective engagement of the inner tube unit with a cable stop bell and its release.

It is now on the 2 and 3 referenced in which the above with reference to the 1 Components described are provided with the same reference numerals.

How out 2 it can be seen comprises the pivot bearing unit 36 for the Bohrkronenende an outer housing 60 , Bearing body 62 and an inner case 64 that with respect to the outer case 60 due to the bearing body 62 freely rotated. ribs 66 with sloping shoulders 68 at their lower ends extend radially inwardly from the inner housing 64 , Ribs 66 and the shoulders 68 support the lower end of the inner tube unit 40 laterally and axially. The space between the ribs 66 allows drilling fluid in the throat 30 the drill bit 24 and the drill bit 28 flows around during core drilling. If this flow is not desired, a drill bit with a weak penetration profile and co-operating shoe can be used after the above mentioned U.S. Patent 4,981,183 , and as in 5 used to minimize the drilling fluid contact with the core. At the bottom of the inner tube 42 can either be a wedge-shaped core catcher 70 as on the left side of the 2 shown, or a basket-shaped core catcher 72 as on the right side of the 2 shown (each in a known per se execution) are used. The PDC cutters 26 are in 2 omitted, however, they are, as in 1 shown on the core bit 24 arranged in such a way that a core is cut out with such a design, that it is up in the neck 30 the core bit 24 and into the hole 74 of the inner tube 42 inside moves.

It is now up 3 Reference is made in the place of the inner tube unit 40 a middle closure unit 80 in the outer tube unit 16 is shown. The middle closure unit 80 comprises at its upper end a locking unit (not shown) similar to that of the inner tube unit 40 , for engagement with the locking coupling 32 of the outer tube 18 as well as a catch coupling 50 for attaching and retrieving the middle closure unit 80 , The closure unit 80 has no pivot bearing, as its rotation with respect to the outer tube unit 16 not required or desired. A drill bit lock 82 is at the bottom of the shutter unit 80 arranged and from the storage unit 36 in the same way as the inner tube unit 40 supported. The drill bit lock piece 82 includes a plug 84 with itself through these extending channels 86 for the passage of drilling fluid to the plug surface 88 on the PDC cutters 90 are arranged. The stopper 84 has such a size that it is from the ribs 66 with the shoulders 68 of the inner housing 64 the storage unit 36 taken up and laterally and axially supported. The spaces between the ribs 66 allow the drilling fluid to flow into the channels 86 , like this 3 shows.

If the intention is to perform a core drilling operation with the device, the inner tube unit becomes 40 left on a rope in the drill string and in the outer tube unit 16 locked. Drilling fluid is then down into the drill string and into the annulus 100 between the inner tube unit 40 and the outer tube unit 16 to circulate where it is from the end face of the core bit 24 through conventional mud channels and nozzles (not shown) to clean and cool the cutting members and also clean the face of the drill bit as the drill string rotates and the formation or core is cut. When the maximum core length has been reached, the inner tube unit will exit the wellbore with a rope with a gear at its end for engagement with the detent coupling 50 pulled and another inner tube unit is driven into the drill string, if another core drilling is intended.

If drilling is intended instead of core drilling, the middle closure unit becomes 80 into the borehole on the rope via a fishing gear, which is connected to the coupling 50 engages at the top of the unit. The closure unit 80 then comes in the outer tube 18 for locking, whereupon drilling fluid down in the drill string into the annulus 100 between the shutter unit 80 and the outer tube 18 and through the channels 86 in the stopper 84 to the stopper area 88 is pumped to the PDC cutters 90 to cool and to clean as well as cuttings while turning the core drill pipe 10 and the progress of the drilling to remove.

If desired, the closure unit 80 with a pressure tube or housing 110 be provided in which a recording tool 12 how a gamma-ray tool or a directional tool for detecting the borehole path can be accommodated for the purpose of measuring when drilling. In this case, furthermore, a data transmission unit 114 in the pressure housing 110 these being an electronic transmission unit or a flushing impulse unit (in which case a part thereof, of course, to the pressure housing 110 outside) for real-time transmission of recording data to the surface via wire or rope or mud. Instead, the data can be periodically by means of rope, or if the closure unit 80 is pulled out of the hole to be caught up.

It is further understood that pressure and temperature sensors in the pressure housing 110 may be included. The former are particularly desirable in order to measure the dynamic pressure loss, and hence the flow rate, for determining those flow rates suitable for core drilling when the central closure unit 80 through the inner tube unit 40 is replaced. By calculating or measuring the hydrostatic pressure in the well annulus and measuring the total pressure near the drill bit from the pressure housing 110 For example, the dynamic pressure loss and thus the flow rates can be determined to reduce or preferably eliminate nuclear erosion.

Temperature measurement is particularly desirable and advantageous when performing a gel core drilling procedure using a non-invasive gel to encapsulate the core sample in the inner tube 42 is placed before it is left in the drill string. The temperature-sensitive nature of such gels and their ability to increase viscosity and even significantly solidify with a drop in temperature in a relatively narrow range makes it possible to measure the core tube depth temperature to an extremely desirable measure, so the formulation or choice a gel that becomes viscous at the desired depth and not prematurely. A more detailed explanation of the formulation and use of non-invasive core sample encapsulation gels may be found in e.g. Currently pending US patent application serial no. 08 / 051,093 of 21.4.1993 of the applicant. The description of this application is incorporated into the present specification by the given reference.

It's up now 4 Reference is made to an example of a spin-free core bit 24 looking down through the drill bit face 200 is illustrated how it is aligned in the borehole. The placements of the PDC cutters 26 are schematically on the Bohrkronenstirnfläche 200 shown. Some cutting elements 26 extend radially inward from the inner calibration area 200 that's the neck 30 the core bit 24 forms, creating a core of smaller diameter than that of the neck 30 can be cut. channels 204 are above the inner calibration range 202 placed so that the Bohrspülungsflüssigkeit, if desired, can flow past the outside of the core. Further flushing channels 220 extend through the drill bit face 200 , Although skid-free drill bits are currently well known, it should be noted that wings 206 and 208 the core bit 24 of cutting members on the outer calibration area 210 are kept free and that Kalibrierstege 212 and 214 on the wings 206 and 208 as support surfaces for the core bit 24 used to run on the wall of the borehole. The selected size, placement, and orientation of the cutting members 26 on the drill bit end face 200 results in a cumulative directed side force vector with an orientation in a direction perpendicular to the bit axis and between the wings 206 and 208 with the effect that the Kalibrierstege 212 and 214 Run substantially constantly against the or on the borehole wall and so prevent vibration and the tendency of Bohrkronenschleuderns.

5 shows a cutter assembly for the inner calibration region on a core bit 248 with a flat penetration profile in cooperation with a core shoe 246 as he mentioned in the above U.S. Patent 4,981,183 is illustrated. The core bit 248 may be in a variety of forms, but preferably has a parabolic basic profile, as is generally the case 251 specified. Instead, other profiles can be used to advantage. For example, generally flat sides can be used which provide the drill bit with a conical shape. The body part 256 the core bit 248 has a plurality of channels 252 on that a flow connection between the annulus 100 in the core tube 10 and outlet openings 240 in the face of the core bit 248 form. A plurality of cutting members 26 , preferably PDC cutting members, is preferably along the profile of the core bit 248 distributed.

The body part 256 preferably has a lower bore 257 on. At least one inside cutter 226 , and preferably two or three such circumferentially spaced cutting members 226 extend inward from the bottom hole 257 the core bit 248 limiting surface to cut an internal dimension, ie the outer diameter of a core 28 , Every single custom cutter 226 is preferably with a flattening 264 formed on Kalibriermaß that is smaller than the bore 257 , Thus, an annular apron or pilot section can 262 of the core drill shoe 246 extend down into such a position that its tip 266 immediately at the top 268 the cutting members 226 in the annulus adjacent to that of the cutting members 226 between the different ones of the flattenings 246 and the lower hole 257 limited diameters is formed. The core bit 248 has on its inner surface over the lower bore 257 a plant 258 on that from the support surface 260 thereby forming a constriction and, ideally, substantially a fluid seal between the rotating drill bit and the stationary core tube. With this configuration, the core outside is precisely cut and the core 28 enters the core drill 246 immediately upon exiting the upper edges of the cutting member flats 246 one. The preferred profile 251 in connection with the orientation and arrangement of the outputs of the channels 252 away from the inner calibration area of the core bit 248 promotes improved flushing of the cuttings and minimizes the effect of the flushing fluid on the core, thereby increasing both the mechanical and chemical integrity of the core sample. It is understood by those skilled in the art that the embodiment according to 2 can be modified to a construction with a shallow penetration profile, that the inner Kalibrierbereich the core bit 24 differently designed and an extended shoe with a pilot area is used, as it is in 5 is shown. The inner case 64 the storage unit 36 may be embodied with channels arranged and oriented in such a way that the flushing medium is guided to channels which guide the flushing liquid to the drill bit end face instead of to the neck or inner calibration area. Of course, the channels would 204 at the inner calibration area, as in 4 shown, omitted.

6 illustrates a first preferred embodiment of a core drilling apparatus 300 with the ability to acquire various data related to different wellbore parameters (well data) during core drilling. The device 300 includes a core tube 302 with a core bit attached to its lower end 304 and an inner tube unit 306 in the longitudinal bore 308 of the core tube 302 in alignment with the neck 310 the core bit is arranged. As stated, it is preferable that the core bit 304 is formed by a PDC core bit, in a particularly preferred manner of a stabilized core bit. The core drilling device 300 is in a borehole from a drill collar 312 through a typical API threaded connection 314 supported downwards.

The core tube 302 has a detent coupling 320 on top of its inside, with which the locking unit 322 the inner tube unit can be releasably engaged to the inner tube unit 306 via a catch coupling 324 or the like. To catch the catch, the bell of a return mechanism such as a catch 326 or the like. Gear at the end of a rope 328 is to capture. The main part of the inner tube unit 306 is rotatably facing downward from the upper locked part by a known rotary bearing unit 330 supported. Possibly. may also include a bearing unit (not shown) at the bit end, as described above, for stabilizing the lower end of the inner tube unit 306 be used. The storage unit 330 and the optional applicable bearing unit at the bit end allow rotation of the core tube 302 around the inner tube unit 306 below the storage unit 330 to cut a core of formation material without its rotational stress, as is well known to those skilled in the art.

The core drill pipe 332 with open mouth 333 at its lower end is positioned so that a through the Bohrkronenhals 310 throughgoing formation core is received. An instrument outflow in the form of an instrument and data transfer module 334 is above the core tube 332 and below the storage unit 330 arranged, the module 334 a pressure housing may be included in which an electronic instrumentation for obtaining well data and at least part of the data transmission device.

By way of example only, the module 334 an instrumentation 336 for determining the wellbore position and orientation (azimuth, inclination, etc.), hereinafter generally referred to as directional instrumentation, and instrumentation 338 for obtaining formation texture data, such as wellbore temperature, wellbore pressure, formation resistance, formation gamma radiation, nuclear magnetic resonance, density, and porosity, hereinafter referred to as formation evaluation instrumentation. The mentioned instrumentations are typically with at least a certain processor capability and with an electronic machine-readable memory, both with 340 designated for storing the obtained data and are in communication with a data transmission device 342 for transmitting real-time data to the earth's surface.

In the device 300 can the data transmission device 342 a mud pulse telemetry unit, an acoustic telemetry unit or a short-cut radio transmitter for transmitting data to another remote data transmitter 344 above the core drilling device 300 for retransmission to the surface of the earth, the remote sending means comprising drilling mud pulse, acoustic and electromagnetic telemetry. Finally, the data transmission device 342 a transmitter for sending data to the earth's surface via the cable connection 328 by a wet bond or other physical or electromagnetic compound as known to those skilled in the art.

It is obviously necessary that some form of power supply 346 is mounted in the inner tube unit for powering the downhole data instrumentation and the data transfer device, and may be formed by batteries (optionally in rechargeable design) and a mud rinse turbine, or a combination thereof, as known in the art. Instead, the current can pass through the cable harness 328 However, such training is less preferred because it is the constant presence of the rope strand 328 required in the drill string during core drilling.

It will be understood by those skilled in the art that the directional instrumentation as well as for use in controlling the wellbore course may also be used to develop and maintain a record of the orientation of the core during its cutting (and desirably is used) such that the core data is correlated with the data in FIG Relationship can be set, which from the the core drill 300 surrounding formation, from which the core sample is cut out.

7 illustrates a second preferred embodiment of a core drilling apparatus 300a in which the previously referring to 6 Components and features described are identified by the same reference numerals. Accordingly, only significant differences between the two core drilling devices in the description of the device 300a cited. In the device 300a is the formation evaluation 338 in the wall of the core tube 302 housed and can be a series of circumferentially around the pipe 302 comprise distributed pressure housings or an uninterrupted annular pressure housing. How through in and out of the instrumentation 338 Directed arrows facilitate such a configuration, the simultaneous recording of formation evaluation data from the surrounding formation and from a core 350 when he's in the mouth 333 of the core drill pipe 332 enters and in this realtiv moves upwards (due to the forward or downward movement of the core drilling unit). Any or all of the above-mentioned types of formation evaluation instrumentation may be used, it being understood that gamma-ray emission, porosity, density, resistance, nuclear magnetic resonance, and sound measurements are particularly suited to the properties of the core 350 be valid. The core tube 302 and the wall and its exterior may thus be rendered transparent to incident and (in some cases) outgoing fields, waves, subatomic particles, and other signals used in making such measurements. It is understood that the various bodies responsible for Sensors for measuring the various downhole parameters are shown and described, depending on the logical location for the best data to be obtained can be varied and thus change the units accordingly.

As stated above, it is highly desirable, if not essential, to determine the orientation of the core (azimuth, vertical angle) both in an absolute sense and for correlation with the measured environmental formation. Other deviations of the device 300a from the device 300 include the arrangement of a processor or processors and an electrical memory 340a as well as a power source 346 in the core tube 302 and the use of the telemetry transmitter 354 to transfer data to a receiver 356 in the inner tube unit 306 for retransmission to the surface via the data transmission or telemetry device 342 which may be a mud pulse generator or other type of system noted above. Furthermore, in the inner tube unit 306 another power source 346 for powering not only the data transmission device 342 , but also the additional processors and the memory 340b as well as the directional elements 336 accommodated. Thus, both formation and direction data may be sent to the surface in real time, and the one or both data may be stored in memory as desired 340b for a periodic removal with the inner tube unit 306 stored for delivery to the surface. It should also be noted that the arrangement of the formation evaluation instrumentation 338 directly on the core bit 304 an extremely advantageous location for the bore parameter instruments 360 to monitor such features as torque, rotational speed, bit weight, vibration and pressure, and directional parameters as discussed above, the latter being for overall control of the borehole path as well as accurately determining the location and orientation of potential zones or layers Interest are beneficial. As shown, the directional instrumentation 336 optionally in the core tube 302 be housed instead of the inner tube unit 306 to be supported.

8th shows a third preferred embodiment 300b a core drilling apparatus according to the invention. As in the embodiment 300a For example, the features and components described above are identified by the same reference numerals and only the differences between the apparatus 300b and those described earlier will be discussed in detail. As shown, the device comprises 300b an instrument tube section 370 above the core tube 302 containing one or more direction, formation evaluation and drilling parameter instrumentation facilities 336 . 338 and 360 presents. The pipe section 370 may include a modified reservoir navigation tool available from the Applicant's INTEQ operating unit. The pipe section 370 contains a power source 346 as well as data processing and storage electronics 340a , Data from the pipe section 370 be via a short-term transmitter / receiver combination 354 and 356 to a data transmission unit 342 in the inner tube unit 306 transmit, which is also a power source 346 and preferably at least one memory 340b if processing capability is not otherwise required in the recoverable unit. Further, as shown, the directional instrumentation 336 in the inner tube unit 306 instead of the pipe section 370 be included, and an additional power source 346 can the directional instrumentation 336 Food. A transmission connection 362 by the directional instrumentation 336 and the memory 340b may be a hardwired connection that uses a slip ring coupling to the bearing unit 360 to pass through or a short-range electromagnetic radio link. Another option is a telemetry unit 342 in the pipe section 370 and to the surface of this data from the instruments in the inner tube unit 306 transferred, in short-circuit connection with the pipe section 370 in an arrangement opposite to the one shown.

9 describes a fourth preferred embodiment 300c the core drilling apparatus according to the invention. As in the earlier figures, the features and elements will, if possible, be referred to by reference numerals already used, and only to significant differences in the apparatus 9 will be described in detail. The device 300c uses a telemetry tube 380 above the core tube 302 , being in the pipe section 380 preferably an acoustic or electromagnetic telemetry or data transmission device 342 is housed. The formation evaluation instrumentation 338 and the drilling parameter instrumentation 360 are in the core tube 302 housed and, as in the embodiment according to 7 , the formation evaluation instrumentation may have the ability to take a survey of a core sample 350 when they are in the core tube 332 emotional. A hardwired telemetry connection 382 can be used to transfer data from the core tube-based instruments to the telemetry tube section 380 via couplings between the core tube and the pipe section 380 as is known per se, or a short-cut radio device may be used. In the same way, the directional instrumentation 336 , (optionally either in the inner tube unit 306 or in the core tube 302 under brought) in short stages to the Telemetrierohrabschnitt 380 Transfers carry out, wherein such a device preferably at a hard-wired connection between the inner tube unit 306 and the core tube 302 or the telemetry section 380 he follows.

It is understood that, as above with respect to 3 described a central plug for drilling the full diameter borehole against the inner tube unit 306 can be exchanged until the interval to be kerned is reached. Furthermore, such a central plug with a data transfer device, an electronic memory and a short-path receiver can be used to transfer data to the surface of the formation evaluation instrumentation 338 , the drilling parameters instrumentation 360 or even from the core tube 302 contained directional instrumentation 336 as above in the embodiments of the 6 to 9 described to transfer. Thus, by real-time evaluation of the formation properties during wellbore drilling, a suitable site for commencement of core drilling in a potential zone or layer of interest can be identified virtually directly and with relatively great precision compared to the prior art techniques. At such point, the central plug is retrieved and an inner tube unit 306 into the core tube 302 used in its place. Likewise, and with appropriate formation evaluation instrumentation during the core drilling operation, a relatively accurate termination of the interval or zone of interest may be determined. At such point, core drilling can be completed, the last core retrieved, and a center plug re-inserted into the core tube to drill forward without core removal. In this way, a plurality of zones of interest can be located and drilled with nucleation, while the intervals between the zones of interest are merely measured and drilled without core removal.

As in 10 As shown, it may be desirable to use the core drilling apparatus of the invention in one embodiment 400 , here with a central plug 402 shown in place, so that the formation evaluation instrumentation 338 within the actual neck 310 the drill bit 304 itself and immediately adjacent to the leading surface 404 of the plug 402 in which cutting members 406 are arranged, is provided. Such sensor proximity to the formation in front of the core drilling apparatus may alter the inner mud channels 408 the core bit 304 , as shown, may not be possible (see the central plug 80 and the channel 86 to 3 ) to guide such channels through the end of the central plug. The channels 408 are only at a central stopper 402 in operation, which is shut off by a corresponding design of the inner tube unit, so as to avoid contamination of the core. Of course, as noted above, the directional and / or drilling parameter instrumentation may also be incorporated into a central plug such as the closure device 80 or 402 be involved.

Although short and long distance telemetry systems have been described above with reference to a single transmitter and receiver for the sake of simplicity, it is readily understood that two way transmission may be desirable in many instances, such as to activate or deactivate the instrumentation Switch instrumentation to another mode or interrogate the instrumentation for calibration or testing purposes. Further, while the above-described instrumentation is all disposed downhole as part of the core drilling apparatus of the present invention, it will be apparent to those skilled in the art that surface instrumentation may be performed on or below the drilling platform to monitor bore related parameters associated with the data received from the downhole instrumentation Relationship can be set and used in conjunction with these. Thus, a surface instrumentation 500 , as in 6 shown in conjunction with a computer 502 and with data being used from the borehole through a receiver 504 be received to the operator data through a display 506 darzubieten. The display may be a digital or graphic display in transient form (such as on a video screen) or permanent (paper, film, electronic storage including magnetic or optical storage, etc.) and, if necessary, by landline, radio telemetry or satellite link to another location be transferred again for further evaluation.

Since ropes, gears, snap-in couplings and interlocking devices, core catchers, bearing units, and other core tube components are known in a wide variety of constructions in the art, these elements have not been described in detail. Likewise, various bypass valve assemblies of various constructions can be used with core tubes of the invention to alternately direct drilling mud through or around the inner tube units and permit displacement of the purge through the core. However, since such devices themselves are conventional in every respect, which are generally known to those skilled in the art, they are neither shown nor described here. Finally, the various types of directional and drilling and formation parameter instrumentation mentioned above are well-known known in the art, as well as the associated data transmission and the like. Electronic devices (processors, memory, power sources, etc.), for which therefore also no detailed description is required.

Although the invention has been described with reference to certain preferred embodiments is, it is not limited to these, and numerous changes the illustrated and described embodiments can be performed without departing from the scope of the invention as defined by the claims is.

Claims (18)

Apparatus for drilling earth formations with a longitudinal bore defining drill body, which is at its upper end to a drill string connected to and provided at its lower end with a core bit, and an instrumentation by which well data are simultaneously receivable with the Erbohren a core, characterized characterized in that at least a portion of the instrumentation is disposed within the tubular body between the outside thereof and the longitudinal bore and receivable by the instrumentation as downhole data earth formation parameters and the instrumentation includes at least one sensor for detecting at least one formation feature from the group of wellbore temperature, wellbore pressure characteristics , Formation resistance, formation gamma radiation, nuclear magnetic resonance, density and porosity. Device according to claim 1, characterized in that at least a portion of the instrumentation is located near the drill bit. Device according to Claim 1 or 2, characterized that by means of the instrumentation substantially simultaneously at least one formation data parameter from a core segment and at least one formation data parameter from a formation outside of the tubular body is receivable. Device according to claim 3, characterized in that that at least one formation data parameter from a core segment and a formation data parameter from a formation outside the tubular body are similar. Device according to one of claims 1 to 4, characterized that within the longitudinal bore a catchable inner tube unit is attachable, the lower portion a recording for having a core drilled by the core bit. Device according to one of claims 1 to 5, characterized through a transmitter for transmission of Data to a remote location from the instrumentation. Device according to claim 6, characterized in that that the transmitter above the lower portion of the inner tube unit is arranged. Device according to claim 6 or 7, characterized the transmitter forms part of the inner tube unit. Device according to one of claims 6 to 8, characterized that the transmitter consists of a Bohrspülimpulsgeber, an acoustic Transmitter and an electromagnetic transmitter comprehensive group is selected. Device according to one of claims 1 to 9, characterized that the instrumentation includes a directional instrumentation, by means of the data relating to the Position and orientation of the device are receivable. Device according to one of claims 5 to 10, characterized that the instrumentation and the lower portion of the inner tube unit has a cooperating one Design for providing registration data for the recorded Core. Device according to one of claims 1 to 11, characterized by a machine-readable memory for storing well data in the device. Apparatus according to claim 7, characterized by a device side arranged above the tubular body receiver to Reception of the transmitter transmitted Data and one with the receiver connected second transmitter for retransmission the data to the earth's surface. Device according to one of claims 1 to 13, characterized that the instrumentation at least one sensor device for determining a parameter which is selected from the following group: emissions of formation gamma rays, Formation resistance, nuclear magnetic resonance, pressure and temperature. Apparatus according to any one of claims 1 to 14, characterized by instrumentation at the surface of the earth for drilling data acquisition, a transmitter near the tubular body for transmitting data from the instrumentation equipment to the surface of the earth, a receiver at the surface of the earth for receiving the data from the transmitter and a computer for processing the received data and surface instrumentation data. Device according to one of claims 7 to 9 or 13, characterized in that the transmitter is arranged above the tubular body is. Method of drilling an earth formation, thereby characterized in that a first borehole section in the earth formation is drilled with a drill string and simultaneously borehole data be picked up without removing the drill string from the well, and that a second borehole section terminating from an endpoint of first section is going to be core-drilled while at the same time Borehole data will be recorded. Method of drilling an earth formation, thereby characterized in that a borehole section drilled in the earth formation will, while at the same time a sizing sample along a longitudinal axis the portion of its leading end is drilled and at the same time at least one borehole parameter is recorded from one location, which is immediately adjacent to a location at which the core sample is separated from the formation.