EP1492935B1 - Method and device for coring and/or directional drilling - Google Patents

Abstract

The invention concerns a method and a device for coring and/or drilling through a wall of a bore hole, to deflect transversely from a longitudinal direction of the hole, further comprising selecting a core barrel ( 1 ) equipped with a core bit ( 3 ) having an inner gauge bore ( 5 ), an arrangement, in the core barrel ( 1 ), of an abrasion resistant internal guide ( 7 ), which is internal at least with respect to the bore ( 5 ) so that the bit ( 3 ) can move along guide ( 7 ), and is designed to deflect the bit ( 3 ) along a desired deflected path, start-up of the coring process with bit ( 3 ) and guiding the bit ( 3 ) through co-operation between its bore ( 5 ) and the guide ( 7 ).

Description

The present invention relates to a method of coring and / or drilling through a wall of a borehole which has been cored or drilled in a subterranean formation, for core drilling and / or transversely deflected drilling from and relative to at a longitudinal direction of the borehole.

Methods and devices of this type are known in which deflection means are provided in the borehole which act on the outside of the drill bit or coring ring. Placing these means in precise locations and orientations of the borehole is complicated and expensive.

Also known is a method and apparatus for milling a hole in a borehole metal casing (see WO98 / 04804).

The object of the present invention is to remedy the problem stated above and to propose a method in which a corer carries, at least the time of carrying out the deflection operation, its own guiding means. Thus, by directly adjusting the depth at which the corer is lowered to begin the deviation, the place from which a deflected core can begin can be set immediately.

For this purpose, the method of the invention comprises, besides a selection of a corer provided with a coring ring having a bore of internal gauge, an arrangement, in the corer, of an inner guide which is made of a material resistant to abrasion of the crown; in addition, before initiating a deviated coring, said guide is internal to at least the bore of internal gauge, so that the crown can circulate along the inner guide. The guide extends in front of the crown, in a coring direction thereof, and is arranged to progressively deflect the ring from said longitudinal direction to the wall, in a desired deflected path direction. The method then comprises starting the coring with said ring and guiding the ring by its inner bore bore cooperating with the inner guide, to penetrate into said wall and into the formation to a desired depth according to the deviated course.

Also detachable to the crown, and in front of it according to its direction of advance of coring, a destructible element which is in a material chosen to be destroyed by the crown, being cored along the deflected path, and which is of a size chosen to pass in the borehole. In the destructible element, a guide means arranged to give the path direction deviated to the inner guide is fixed.

According to an advantageous embodiment of the invention, the aforesaid internal guide is used as a guiding means in the destructible element, and the destructible element is fixed to the borehole wall in a location chosen for a deflected core. . Next, the detachable attachment between the crown and the destructible element is broken, and the crown is rotated and pushed forward to follow the deviated path given by the internal guide, destroying the part of the destructible element that it meets and penetrating into said wall and into the formation to a desired depth.

Note that in this case the inner guide is fixed in the borehole by the destructible element, until the crown has completely detached from the destructible element.

According to another advantageous embodiment of the invention, the method comprises, before the deviated coring proper, an arrangement, as a guide means in the destructible element, of a guide channel whose one end is substantially coaxial with the bore of internal gauge and whose path corresponds to the desired deviated path. Then there is available, in particular in stages, a drill rig, carried by a drill string, through the corer and the bore of internal caliber and along the guide channel. A drilling is carried out by the machine in the wall of the borehole according to the deviated path given by said channel, the drill string having a length chosen so that, when the drill rig is driven into the wall to a depth of d anchoring chosen, the drill string is still engaged in at least the bore of inner caliber of the crown. Then, it provokes a break of the detachable attachment between the crown and the destructible element, and is rotated and pushed forward the crown following the deflected path given by the drill string and the drill rig, to destroy the portion of the destructible element and said guide channel that it meets and to penetrate into said wall and into the formation to a desired depth.

Note that in this case the inner guide is previously sent and stuck in the wall of the borehole, to fix it, before the crown is put into action. Then, the crown actuated will be advanced along the inner guide to release it from its fixation in said wall. We can then provide a withdrawal of said inner guide through the corer when it has been deflected.

According to yet another advantageous embodiment of the invention, the method comprises, before the deviated coring itself, an arrangement, as a guide means in the destructible element, of a guide channel, one of which end is substantially coaxial with the bore of internal gauge and whose path corresponds to the desired deviated path. In this case, the destructible element is fixed to said borehole wall at the location chosen for the deflection. A drilling apparatus, carried by a drill string, is arranged through the corer and the bore of internal gauge and that it follows the guide channel towards said wall. The drilling machine is fixed to the corer, so that it projects from a determined distance out of the crown into the guide channel. The detachable fastener between the crown and the destructible element is broken and the crown and the drill rig are rotated and pushed forward and a drilling is carried out by the machine in the wall of the vehicle. borehole, according to said deflected path given by the guide channel, and core coring according to the deflected path given by the drill string and the drill, destroying the portion of the destructible element and said channel guide it meets and penetrating into said wall and into the formation to a desired depth.

Note that in this case the inner guide moves forward of the crown, at the same time, and in principle of the same value, as the crown but can also organize a withdrawal of said inner guide through the corer when it will have been diverted.

The invention also relates to a device for coring and / or drilling through a wall of a borehole which has been cored or drilled beforehand into an underground formation, for core drilling and / or transversely deflected drilling from and through relative to a longitudinal direction of the borehole.

The device of the invention comprises a corer, provided with a coring ring having an internal bore, and an inner guide which is made of a material resistant to abrasion of the crown, which, before initiating a coring deflected, is interior to at least the bore of internal caliber, so that the crown can circulate along the inner guide, which extends in front of the crown, in a direction of advance of coring thereof , a destructible element (9), which is detachably secured in front of the ring gear (3) in the coring direction thereof, is of a material selected to be destroyed by the ring gear (3) being coring and / or deviated drilling, and is of a size chosen to pass into the borehole, and in which is fixed a guide means (11) arranged to give a deviated path direction to the inner guide extending in front of the crown, the inner guide being, during the coring and / or deflected drilling, held fixed so as to give the crown (3) said desired deflected path direction and to progressively deflect the ring (3) from said longitudinal direction towards the wall .

• Les figures 1 à 20 représentent schématiquement, sans échelles déterminées, en coupe suivant l'axe longitudinal et avec brisures différents tronçons successifs de trois différentes formes de réalisation d'un dispositif suivant l'invention. Lesdites figures sont orientées dans un même sens, l'extrémité antérieure d'un tronçon étant dans le bas du dessin, l'extrémité postérieure étant dans le haut. Dans une même forme de réalisation, l'extrémité postérieure d'un tronçon d'une figure est à faire suivre par l'extrémité antérieure du tronçon de la figure suivante, l'endroit de fixation de l'élément destructible à la couronne étant reproduit sur deux figures consécutives.
• Les figures 1 à 4 montrent la première forme de réalisation, la figure 1 en montrant l'extrémité antérieure, la figure 2 montrant un tronçon suivant dans le sens vers l'extrémité postérieure, la figure 3 montrant le tronçon suivant celui de la figure 2, la figure 4 montrant le tronçon postérieur à raccorder à un train de tiges.
• Les figures 5 à 9 montrent d'une même manière la seconde forme de réalisation dans son montage de guidage de déviation, la figure 5 montrant l'extrémité antérieure du dispositif et la figure 9 montrant le tronçon postérieur à raccorder à un train de tiges.
• Les figures 10 à 12 montrent d'une même manière la seconde forme de réalisation dans son montage de carottage.
• Les figures 13 à 17 montrent d'une même manière la troisième forme de réalisation dans son montage de guidage de déviation, la figure 13 montrant l'extrémité antérieure du dispositif et la figure 17 montrant le tronçon postérieur à raccorder à un train de tiges.
• Les figures 18 à 20 montrent d'une même manière la troisième forme de réalisation dans son montage de carottage.
• Les figures 21 à 23 montrent à d'autres échelles des coupes transversales de détails de construction, prises respectivement suivant les plans de coupe XXI-XXI de la figure 8, XXII-XXII de la figure 7 et XXIII-XXIII de cette même figure 7.

Other details and particularities of the invention will emerge from the secondary claims and the description of the drawings which are appended to the present document and which illustrate, by way of non-limiting examples, the method and particular embodiments of the device according to the invention. 'invention.

• Figures 1 to 20 show schematically, without scales determined in section along the longitudinal axis and with broken different successive sections of three different embodiments of a device according to the invention. Said figures are oriented in the same direction, the front end of a section being in the bottom of the drawing, the rear end being at the top. In the same embodiment, the rear end of a section of a figure is to be followed by the front end of the section of the following figure, the location of attachment of the destructible element to the crown being reproduced in two consecutive figures.
• FIGS. 1 to 4 show the first embodiment, FIG. 1 showing the front end, FIG. 2 showing a following section in the direction towards the posterior end, FIG. 3 showing the section following that of FIG. 2. , Figure 4 showing the posterior section to be connected to a drill string.
• Figures 5 to 9 similarly show the second embodiment in its deflection guide assembly, Figure 5 showing the front end of the device and Figure 9 showing the rear section to be connected to a drill string.
• Figures 10 to 12 show in a similar manner the second embodiment in its coring assembly.
• Figures 13 to 17 similarly show the third embodiment in its deflection guide mounting, Figure 13 showing the front end of the device and Figure 17 showing the rear section to be connected to a drill string.
• Figures 18 to 20 show in a similar manner the third embodiment in its coring assembly.
• FIGS. 21 to 23 show at other scales transverse sections of construction details taken respectively along the sectional planes XXI-XXI of FIG. 8, XXII-XXII of FIG. 7 and XXIII-XXIII of this same FIG. .

In the various figures, the same reference notations designate identical or similar elements. However, in the third embodiment, certain elements of the same kind and / or function as those of the second embodiment, but different in their design, will receive the same completed number of the letter "t".

For the sake of clarity, the device of the invention intended for coring and / or deflected drilling is first described, through a wall of a borehole (not shown) which has been cored or drilled beforehand. in an underground formation (not shown)

According to one of its embodiments, the device of the invention (FIGS. 1 to 4) comprises, on the one hand, a corer 1 provided with a coring ring 3 (FIG. 1) having a bore of internal caliber 5 and, on the other hand, an internal guide 7 which is made of a material resistant to abrasion of the ring gear 3, in particular to that of the abrasive elements usually arranged in its internal bore bore 5. Before starting a deflected core , the inner guide 7 is arranged inside at least the internal bore bore 5, so that the ring 3 can circulate along the inner guide 7. In addition, the inner guide 7 s' extends in front of the ring gear 3, in a coring direction thereof, and is arranged to progressively deflect the ring gear 3, from said longitudinal direction of the previously-formed borehole, to the wall of said borehole. The inner guide 7 is held fixed relative to said wall to give the crown 3 the desired direction of deflection.

Hereinafter, by the front end of an element, we designate the one closest to the bottom of the borehole when the corer 1 is disposed in the coring position, and the rear end of an element, the one closest to a derrick which is connected to said corer 1 for coring.

Said device of the invention may further comprise a destructible element 9 which is detachably fixed in front of the ring 3, in the direction of the coring advance thereof, and which is made of a material chosen to be destroyed by the crown 3 being cored along the deflected path. The destructible element 9 is of a size chosen to pass into the borehole.

The destructible element 9 can be made of any known material, composite or not, that the crown 3 can destroy in its passage without it wearing down unnecessarily, but which can keep the guide means 11 and / or or the internal guide 7. It may be for this purpose a block of cement, polyester, a composite material, etc..

In the destructible element 9 is fixed a guide means 11 arranged to give the deviated path direction that the crown 3 must follow.

The destructible element 9 may include means 13 for its selective attachment to the wall of the borehole.

Said selective attachment means 13 may comprise an annular sleeve 15 of elastic material, which is mounted on a peripheral side surface portion of the destructible element 9 and whose outside diameter at rest passes freely in the borehole but may be selectively expanded to lock against the wall of the borehole, means 17 being provided to cause this expansion and to preserve it. The annular sleeve 15 is for example fixed by one of its ends 15A to the destructible element 9 while its other end 15B is arranged to be able to slide sealingly along said destructible element 9.

The means 17 designed to cause the expansion may comprise an annular chamber 19, between the annular sleeve 15 and the destructible element 9, means 21 for supplying fluid to this annular chamber 19 as well as locking means 23, in particular a valve 23 ball and spring, arranged to selectively lock in the annular chamber 19 the fluid that has been fed.

Other suitable selective attachment means 13 different from those described can be used for the implementation of the invention.

Preferably, the detachable fastener between the destructible element 9 and the ring gear 3 is arranged to detach itself by relative rotation of the ring gear 3 with respect to the destructible element 9 fixed beforehand to said wall.

For this purpose, said detachable attachment between the destructible element 9 and the ring gear 3 may comprise at least one and preferably several pins 25 fixed each time through a nozzle 27, the ring 3, provided as an output of coring fluid on the front face of the crown 3. This pin 25 is advantageously partially tubular and open at its end facing the inside of the ring 3, its inner hollow extending beyond the nozzle 27 to the outside of the crown 3. The pin 25 is closed at its end outside the ring 3. It is arranged to break, during said relative rotation, between the ring 3 and the destructible element 9, there wherein it is hollow, and is preferably of a material that can be removed, for example by wear, from the coring fluid passing through the tubular pin 25 broken and / or in the corresponding nozzle 27. In the example of Figures 2 and 3, the pin 25 has a thickening 25A at its inner end to the ring 3, so as to be locked in the nozzle 27 when it is pushed in to exit outside of the crown 3 and pass into the destructible element 9. At its other end, the pin 25 can receive a washer of elastic material 28 and a nut 28A for locking the destructible element 9 on the crown 3. The pin 25 can be made in particular of synthetic material, aluminum or alloy thereof.

The pins 25 which serve to detachably fasten between the ring 3 and the destructible element 9 thus clog all the nozzles 27 in the present embodiment of the invention.

According to this first embodiment of the invention, represented in FIGS. 1 to 4, said guide means 11 is the aforementioned internal guide 7 fixed in the destructible element 9.

In the case of example of Figure 3, the inner guide 7 has a rear end 29 inserted coaxially in an inner tube 31 of the corer 1, which is mounted in a known manner in an outer tube 33 of the same corer 1. The guide 7 passes through the internal bore bore 5 and (Figures 3 and 2) extends first coaxially into the rear end 35 of the destructible element 9 and then curved towards, and up to , the lateral surface 37 of the destructible element 9 where the inner guide 7 is preferably shaped to fit into the outer shape of said lateral surface 37. The rear end 29 of the inner guide 7 and at least a part of it are pierced with a longitudinal channel 39 preferably of the same axis as the longitudinal axis 41 of the corer 1 and the destructible element 9, this longitudinal channel 39 being extended along the same direction to the so upape 23 fastening means 13 to the wall of the borehole. As shown in FIG. 2, the longitudinal channel 39 thus progressively leaves the internal guide 7 and leaves it because of the curvature of the latter and the rectilinear pattern of said channel 39. Notably for this purpose, said longitudinal channel 39 can be drilled. in the inner guide 7 and destructible element 9 previously assembled.

The outer tubes 33 and inner 31 are usually formed each of several successive sections fixed in known manner to one another.

The internal space 43 (FIG. 4) of the inner tube 31 may advantageously comprise a piston system 45 which separates this inner space 43 in an upper space 47 in which coring fluid can be brought to controlled pressure from the inside. terrestrial surface, and a lower space 49 in which a different particular fluid can be enclosed before lowering the corer 1 into the borehole. This particular fluid may be a carrot protection fluid, which may be used, as explained hereinafter, to inflate the annular sleeve 15. For this purpose, this particular fluid preferably does not contain particles that could impede the smooth operation. of the valve 23 in particular.

• à travers la paroi du tube intérieur 31, un passage muni d'un bouchon 51,
• sur le pourtour du piston 45, un dégagement annulaire 53 délimité par deux joints toriques 55, et par ladite paroi du tube intérieur 31,
• dans le piston 45, un passage transversal 57 entre ce dégagement annulaire 53 et une soupape 59 à bille et ressort,
• une sortie de fluide de la soupape 59 vers l'espace inférieur 49,
• dans le piston 45, un passage longitudinal 61 entre l'espace inférieur 49 et une soupape 63 à bille et ressort destinée à l'évacuation d'un surplus de fluide particulier, et
• une sortie 65 du fluide de la soupape 63 vers l'espace intérieur 43 et plus particulièrement vers son espace supérieur 47.

For the introduction of the particular fluid into the lower space 49 when the piston system 45 is in the position shown in FIG. 4, it can be provided

• through the wall of the inner tube 31, a passage provided with a plug 51,
• on the periphery of the piston 45, an annular clearance 53 delimited by two O-rings 55, and by said wall of the inner tube 31,
• in the piston 45, a transverse passage 57 between this annular clearance 53 and a ball valve 59 and spring,
• a fluid outlet of the valve 59 to the lower space 49,
• in the piston 45, a longitudinal passage 61 between the lower space 49 and a ball and spring valve 63 for discharging a particular excess fluid, and
• an outlet 65 of the fluid of the valve 63 towards the interior space 43 and more particularly towards its upper space 47.

This particular fluid is introduced by this path into said lower space 49 before putting the inner tube 31 in the outer tube 33.

The inner tube 31 is suspended in known manner in the outer tube 33 by means of a thrust ball system 67 (Figure 4).

Coring fluid can be passed through the stop system 67 and can flow to the gap 69 between the outer and inner tubes 33 through openings 71 and to the top of the piston 45 through an orifice 73 as long as the it was not closed by a ball 75.

A first embodiment of the method of the invention may be described using the device of the invention according to the embodiment described above, without however being limited to the use of this device.

In addition to a usual selection, according to the work to be done, of a corer 1 provided with a coring ring 3, an internal guide 7 of the type described is arranged in the corer 1, which, before initiating a deviated coring, is arranged inside at least said bore of internal caliber 5, so that the ring 3 can circulate along the inner guide 7. The latter is arranged to extend in front of the ring 3, following a direction of coring advance thereof, and is arranged to progressively deflect the ring 3 from said longitudinal direction of the borehole to the wall thereof.

The inner guide 7 is held fixed with respect to the wall of the borehole to provide the crown 3 with a desired deflected path direction. The coring is started with said ring 3 thus equipped and it is allowed to carry out a guide of the ring 3 by its bore of internal gauge 5 along the inner guide 7, to penetrate into said wall and in the formation until to a desired depth following the deflected path.

In a variant of the method of the invention, to fix the position of the inner guide 7 relative to said borehole wall, it is advantageously releasably attached to the crown 3, in front of it in its direction of advance of coring, the destructible element 9 aforesaid, in particular using the pins 25 described.

Then fixed in this destructible element 9 a guide means arranged to give the deviated path direction.

In particular, it is possible to directly use the internal guide 7 as aforesaid as guide means 11 in the destructible element 9 or vice versa, the inner guide 7 and the guide means 11 being merged into one piece.

The particular fluid mentioned above can be introduced into the interior space 43 only at the moment when the destructible element 9 and the internal guide 7 are attached to the corer 1, so as to also fill the longitudinal channel 39 to at least the valve 23, and preferably into the annular chamber 19, purging the air that would be there.

The corer 1 can then be lowered into the borehole and the destructible element 9 to be fixed to the borehole wall at a location chosen for a deviated core. For this purpose, drilling fluid that is sent under pressure in the corer 1 and can not flow through the nozzles 27 blocked by the pins 25, is forced to pass through the orifice 73 and act on the face of the piston 45. The piston 45 thus urged pushes the particular fluid through the longitudinal channel 39 so that this fluid opens the valve 23 and passes through holes 24 in the annular chamber. 19 to fill the latter and thus push the annular sleeve 15 into a most intimate contact with the wall of the borehole. This blocks in the borehole destructible element 9 and corer 1 attached thereto. When the pressure of the coring fluid is reduced or temporarily canceled, the piston 45 releases the pressure of the particular fluid and the valve 23 is closed by the action of its spring as well as possibly by a reverse pressure caused by the annular sleeve 15. The annular chamber 19 remains filled and the annular sleeve 15 remains in blocking contact to maintain fixed in translation and in rotation the position of the destructible element 9 in the borehole.

So that the pressure of the coring fluid no longer solicits the piston 45, it is advantageous to launch in the corer 1, as is known, a closing ball 75 (FIG. 4) calibrated to reach the orifice 73 and seal this one.

As the destructible element 9 is thus fixed in the borehole, when the ring gear 3 is rotated through the outer tube 33, the pins 25 are caused to break. The coring fluid can now pass through the tubular portion of each spindle 25 remaining in its respective nozzle 27, and abrade this tubular portion until sufficient or all of said nozzle 27 is released.

It is then necessary to continue the rotation of the ring 3 and push it forward so that it follows the deviated path given by the internal guide 7 thus fixed to the wall of the borehole, destroying the part of the destructible element 9 that it encounters and penetrating into said wall and into the formation to a desired depth.

Said particular fluid remaining in the interior space 43 or more precisely in the lower space 49 can serve, if it has been chosen for this purpose, to coat the core as it enters this lower space 49, the surplus this fluid can escape for example through the valve 63 and, by pushing the ball 75, mix with the coring fluid in the gap 69.

It is understood that the curvature that can be given to the inner guide 7 is of a very large radius, and that consequently the length of this inner guide 7 is important, because the deviation that it can give the corer 1 is weak because of the rigidity of the latter. When selecting the corer 1, this length will therefore be taken into account in the calculation of that of the interior space 43 in which the internal guide 7 will enter and remain. For this purpose, the inner guide 7 may advantageously have, outside the destructible element 9, a certain flexibility so as to be able to recover slightly when it arrives and is in the inner tube 31.

In FIG. 2, it can be seen that the internal guide 7 opens, from the inside of the destructible element 9 towards the lateral surface thereof, between two stabilizing wings 77. It could equally well lead through such a wing 77.

It appears that, for example, the anterior portion of the destructible element 9, which carries the fastening means 13 (sleeve 15) to the wall, remains substantially in place in the borehole when removing the corer 1 after the deviated coring. This portion, profiled in the corner by the action of the ring 3 can therefore serve as a guide to reintroduce according to the same deviation the same corer 1 or another or even a drilling device. This same wedge-shaped front portion may, however, be subsequently detached from the wall and / or destroyed to allow for a coring and / or drilling operation deviated to a deeper level in the same starting borehole.

In a second embodiment of the invention (FIGS. 5 to 12 and 21 to 23), said guide means 11, formed in the destructible element 9, is a guide channel 79, in particular of cylindrical tubular shape, one of which end is substantially coaxial with the internal bore bore 5 of the crown 3 and whose path corresponds to the desired deviated path, to open, cut obliquely, the lateral surface of the destructible element 9, as shown in the Figures 5 and 6, so as not to overflow this side surface.

In this second embodiment of the invention, an intermediate guide tube 81 can be arranged in the outer tube 33, in order to temporarily accommodate, on the one hand, a removable assembly 83 comprising the internal guide 7 which will cause the desired deviation and, secondly, then an inner tube 31 which will later receive a core. A gear coupling 84 (FIGS. 7 and 22) can be provided between the intermediate and outer tubes 81 to secure them with respect to their rotation. It will be noted the passages for the fluid, formed between the teeth carried by the intermediate tube 81 and the bottoms of the recesses between the teeth of the outer tube 33. The intermediate tube 81 may include known centering means 85 (FIGS. 8 and 11), having longitudinal passages for fluid. The removable assembly 83 comprises, in order to be able to remove it from the corer 1 (FIG. 9), a hooking stud 86.

The inner guide 7 itself comprises a drilling device 87 (FIG. 6) carried by a drill string 89 (FIGS. 7 and 8), and is arranged to be passed through the corer 1 into the intermediate tube 81. through the bore of inner bore 5 and following guide channel 79 so as to be able to drill and penetrate into the wall of the borehole according to said deflected path given by guide channel 79. The drill string 89 has a length chosen so that, when the drill rig 87 is driven into said wall according to a chosen anchoring depth, the drill string 89 is still engaged in at least the bore of internal gauge 5. For example, the drill rig 87 comprises a drilling head 91 and, to rotate it, a hydraulic motor 93 known per se, fed with drilling fluid at its rear end 95, through the drill string 89 hollow, from the outer tube 33.

In the case described here, the destructible element 9 (FIGS. 5 and 6) is not equipped with the means 13 shown in FIG. 1 (and described above) for the selective attachment to the borehole wall, and this means is not necessary in said second embodiment. As a result, there is no need to close all nozzles 27 by pins 25 (Figure 6).

In the case of the second embodiment, the removable assembly 83, which is proposed by way of example for manipulating the inner guide 7 in the intermediate tube 81, may comprise a removable tube 97 arranged to slide in the intermediate tube 81 and in which is housed the drill string 89 of the drill rig 87.

The method associated with said second embodiment may then comprise an arrangement, as guiding means 11 in the destructible element 9, of the guide channel 79 arranged as explained above.

For example, at the coring assembly 1, the drill rig 87, carried by its string of rods 89, through the corer 1 and the internal bore bore 5, so that it follows the guide channel 79, preferably so that the drill head 91 is positioned (as shown in Figure 6) at a still laterally closed position of said guide channel 79 but close to the front end thereof.

For this purpose, the drill string 89 to which the drill rig 87 is suspended is held by a breakable pin 99 (FIGS. 7 and 23) which passes through the drill string 89 in a transverse sealing tube 101 which is fixed thereto sealing. The breakable pin 99 can be retained on both sides in the removable tube 97 which is arranged (indirectly) to abut against the inside of the ring gear 3. The body of the motor 93 is prevented from rotating by its attachment to the gear train. rods 89 which, in the exemplary embodiment, comprises on its external surface two longitudinal grooves 103 cooperating with two inner projections 105 of the removable tube 97. The removable tube 97 itself is prevented from rotating for example by a spring pawl 106 (Figure 9) that it comprises and which cooperates for this purpose with a longitudinal groove 107 cut in the intermediate tube 81 locked in rotation on its side by the gear coupling 84 in the outer tube 33 which does not rotate during this phase of operation.

Drilling or coring fluid is sent under pressure into the corer 1 from its posterior end 109 (FIG. 9) and passes into the intermediate tube 81 which it simultaneously pushes against (directly or indirectly) against the crown 3. This fluid passes along the attachment pin 86 and the spring pawl 106, through passages 111, and through a selector piston 113 held by a breakable pin 115 in a position shown in Figure 9. From there, the fluid flows through a nozzle 117 and inside the removable tube 97 and (Figure 8) arrives at the posterior end of the drill string 89 which is arranged in a kind of piston in the removable tube 97 and is provided with a nozzle 117 for restricting the passage of the fluid. Said fluid pushes by its pressure on the drill string 89 and, traversing this drill string 89, reaches (Figure 7) the motor 93 which it rotates to rotate the drill head 91. The breakable pin 99 is broken under a controlled pressure of the fluid and the drill rig 87 can then advance to the wall of the borehole.

Thus is caused a drilling by the machine 87 in the wall of the borehole according to said deviated path given by the guide channel 79. The drill string 89 has a length selected so that when the drill rig 87 is pressed into said wall according to a chosen anchoring depth, the drill string 89 is still engaged in at least the bore of internal caliber 5 of the crown 3.

Advantageously, (FIGS. 8 and 21) an outer sleeve 119 is slidably and sealingly mounted on the drill string 89, in a position depending on the chosen anchoring depth, and is fixed to said train 89, in the drawn position, by a breakable pin 121 which passes through the train 89 into another transverse sealing tube 122 similar to the previous tube 101. This outer sleeve 119 closes in this position one or more orifices 125 formed through the wall of the drill string 89.

When the drill string 89 has traveled in the removable tube 97 the distance chosen for anchoring, said outer sleeve 119 abuts (FIG. 7) against a stop shoulder 123 and, under the force exerted by the pressure of the fluid pushing said train 89, the breakable pin 121 breaks and the drill string 89 still advances, in particular in said sleeve 119 (Figure 8), a predetermined length. By this movement, the sleeve 119 releases the orifices 125 and this makes the pressure of the fluid fall in the corer 1. As a result, the motor 93 no longer has the force to drill the head 91 and simultaneously the operator of the corer 1 can see the pressure drop on a manometer on the surface and understand that this drilling is completed.

At this stage of the operations with the second embodiment of the invention, the destructible element 9 (FIGS. 5 and 6) is fixed in the borehole by the drill rig 87 driven in the manner of a nail into the training (position not shown).

For example, a sudden sudden rise in pressure of the fluid is caused at this moment and it acts on the selector piston 113 (FIG. 9) with a force which causes the rupture of its breakable pin 115 and the displacement of said selector piston 113 in the room he occupies, towards the crown 3, until opening a passage for said fluid through orifices 127 which lead it into the space 129 between the outer tubes 33 and intermediate 81, so that this fluid arrives by this path to the nozzles 27 to be able to start l deflected core operation itself.

It is necessary to cause at this moment the rupture of the detachable fastener between the ring gear 3 and the destructible element 9. For this purpose in particular, the ring gear 3 is rotated by means of the outer tube 33, the element destructible 9 being locked in rotation by the drill rig 87 stuck in the formation. This breaks the pins 25. It retains said rotation and is pushed forward the corer 1 which can only follow the deviated path given by the drill string 89 and the drill rig 87, destroying the part of the destructible element 9 and said guide channel 79 that the ring 3 encounters and penetrates into said wall and into the formation around the borehole to a desired depth.

At this stage of operations, it can for example remove the removable assembly 83, thus said inner guide 7 formed by the drill rig 87 and its accessories, catching in known manner the hooking nipple 86 of this assembly. It is then possible to introduce into the corer 1, more precisely into its intermediate tube 81, an ordinary inner tube 31 (FIGS. 10 to 12) using a hooking stud 86 thereof.

In the example described hereinbefore, the internal space 131 (FIGS. 10 and 11) of the inner tube 31 may be filled beforehand and in a known manner with another fluid, in particular for the protection of the core that will enter it. The front end (FIG. 10) of this interior space 131 may then be provided with a piston 133 for distributing this other fluid around the perimeter of the core. For this purpose, the piston 133 may comprise a valve 135 whose rod 137 bears on the top of the core at the beginning of the entry thereof into the inner tube 31 and whose displacement releases a passage for the fluid to through the distribution channels of the piston 133 which open to the top of the carrot, as the carrot enters.

At the rear end of said interior space 131 (FIG. 11), it may be provided, for example, a ball 138 arranged to allow the other fluid, contained in the inner space 131 and in surplus when the core penetrates into it, to be able to to escape and to prevent the pressure coring fluid coming from outside this interior space 131 enters it.

In a third embodiment (FIGS. 13 to 20) of the device of the invention, said guide means 11 (FIGS. 13 and 14), in the destructible element 9, is also a guide channel 79 whose end is substantially coaxial with the inner bore bore 5 of the ring 3 and whose path corresponds to the desired deviated path. The inner guide 7 also comprises a drill rig 87t carried by a drill string 89t and arranged through the corer 1 and the internal bore bore 5 and following the guide channel 79 towards said wall. The drill rig 87t and its drill string 89t are mounted in the corer 1 so that the machine 87t projects from a predetermined distance out of the ring 3 into the guide channel 79. The drill head 91t the machine 87t could also be rotated by a motor as in the second embodiment.

However, in the example of Figures 14 to 17, said drill head 91t does not have a motor but is coupled by the drill string 89t to the ring 3 of the corer 1 as explained below.

For this purpose, the drill rig 87t and its drill string 89t form a removable assembly 83t that is installed in the intermediate tube 81 to come directly or indirectly to stop against a stop in the ring 3, so that that the drilling head 91t is at the desired distance ahead of the crown 3. A spring pawl 139 (Figure 15), which is part of the removable assembly 83t, engages in a longitudinal groove 141 cut in the tube intermediate 81 so that it, when rotated by the outer tube 33 via the gear coupling 84, rotates the removable assembly 83t and thus the drill head 91t which is part thereof and is also attached to it for rotation.

In the case currently described, since the ring gear 3 must rotate to ensure the rotation of the drill head 91t, it is necessary to fix the destructible element 9 (FIGS. 13 and 14) accordingly to the wall of the borehole, for example with the same elements, such as the inflatable annular sleeve and its accessories, and in the same manner as in the case of the first embodiment.

To supply inflation fluid to the sleeve 15, the supply means 21 (FIGS. 13 to 15) may comprise, besides the valve 23 and the through-holes 24 described previously in the first embodiment, a conduit 143 arranged parallel to the longitudinal axis 41 and connecting for the fluid the interior of the guide channel 79 to the valve 23. In order for said inflation fluid to pass into this conduit 143 at the desired moment, the guide channel 79 is closed by a hermetic plug 145 disposed temporarily in front of the drill head 91t (Figure 14).

The method of the invention, applied in the context of this third Embodiment of the corer 1 may include the following steps, some of which are essential to the invention and others are only necessary for understanding (as is also the case for the other forms and embodiments).

For example, a corer 1 is mounted as shown in FIGS. 13 to 17 and the guiding channel 79 arranged as explained above is arranged as guide means 11 in the destructible element 9. During this assembly, the drill rig 87t, carried by the drill string 89t, is arranged, in particular, through the core drill 1 and the bore of internal gauge 5 and following the guide channel 79 towards the said wall. drill. The drill rig 87t is fixed to the corer 1, so that it projects from a determined distance out of the ring gear 3 into the guide channel 79. This attachment will presently be the result of the pressure of the drilling / coring fluid. on the removable assembly 83t, pushing the latter against the inside of the ring 3.

It is then possible to pour into the intermediate tube 81 a fluid that is preferably particular, without particles so as not to hinder the proper functioning of the valve 23, so that a sufficient quantity of this fluid is stored in the conduit 143, the channel guide 79 closed by the plug 145 and the drill string 89t to subsequently ensure proper inflation of the sleeve 15.

The corer 1 can then be lowered into the borehole and positioned where the deflected core is desired. The destructible element 9 is then attached to said wall of the borehole, as already described, by inflating the sleeve 15 with the particular fluid subjected to a sufficient pressure sent into the corer 1 from the derrick. , in particular using a coring / drilling fluid pressing on the particular fluid.

It is necessary to cause at this time a rupture of the detachable fastener between the ring 3 and the destructible element 9. For this purpose, it puts in this case the ring 3 in rotation and, the destructible element 9 being blocked by the fastening means 13 in the borehole, the pins 25 break. It will be appreciated that in order to pressurize the fluids, all the nozzles have been plugged by pins 25 of the type described above.

We can continue the rotation of the ring 3 and push it forward through the destructible element 9 it destroys in its path, along with the guide channel 79 therein. The ring 3 drives in its stroke the drill rig 87t which precedes it, the core drilling fluid / drilling forward the train of rods 89t. The drill head 91t drills and first removes the plug 145 and can then drill the wall of the borehole along said deflected path given by the guide channel 79. The ring 3 then follows the deflected path given by the drill string. 89t and the drill rig 87t, penetrating into said wall and into the formation to a desired depth.

It can be seen in FIG. 14 a membrane 147 which, when intact in its drawn position, prevents the fluid or fluids from passing towards the outside of the destructible element 9. In fact, when the sleeve 15 has been sufficiently inflated, the fluid can be given a momentary overpressure capable of piercing this membrane 147 so that, from this moment, fluid can escape at this point and rise towards the crown 3

At this stage of operations, the detachable assembly 83t which comprises the drilling rig 87t can be removed by means of the pin 86 and replace this assembly 83t, as in the case of the second embodiment above, by a usual inner core tube 31 (FIGS. 18 to 20) already described.

As an alternative of the third embodiment, when the drill rig has penetrated a desired depth into the wall of the borehole, it may be chosen to reduce the pressure of the coring fluid in the core core 1 so that the drill rig 87t is no longer pushed forward in the formation and the head 91t no longer drills or barely. Under these conditions, if the ring 3 continues to progress in the destructible element 9 and / or in the formation, the removable assembly 83t enters the corer 1 in the intermediate tube 81. The ratchet system 139 and longitudinal groove 141 can be arranged so that from a retracted position of the removable assembly 83t, the pawl 139 comes out of this groove 141. As a result, the head 91t is then no longer rotated and does not progress any further. everything in training. If the ring 3 is still driven in rotation and pushed forward, it can progress while being guided by the drill rig 87t and / or its drill string 89t.

It appears to those skilled in the art that the second and third embodiments of the invention give the crown 3 guiding greater than that given in the first embodiment, since the internal guide 7 of these two cases is available until beyond the interface between the destructible element 9 and the formation.

In addition, in the second and third embodiments, if the drill rig 87 or 87t is passed deep enough into the borehole wall formation, then the cut core will be fully formed. and not a first portion consisting of debris of the destructible element 9 and a second portion consisting of said formation with, between these two parts, an interface surface oblique to the coring direction.

It should be understood that the invention is not limited to the embodiments described and that many modifications can be made to them without departing from the scope of the claims.

In the description and the claims, the indicated order of the process steps currently seems favorable. However, modifications of this kind must be considered as falling within the scope of the claims.

The stabilizing wings 77 of the destructible element 9 are shown extending parallel to the longitudinal axis 41. However, they can be of helical shape.

• être disposé entre le tube extérieur 33 et le tube intérieur 31 ou respectivement intermédiaire 81,
• présenter une grande chambre annulaire 153,
• présenter une petite chambre annulaire 155 reliée à la grande chambre 153 et qui est ouverte au moins localement du côté de la carotte,
• être en appui ou fixé contre l'intérieur de la couronne 3.

FIGS. 3, 7, 10, 15, and 18 will show an apparatus 151, which is not detailed and can be mounted as a variant or omitted, and which can

• be disposed between the outer tube 33 and the inner tube 31 or respectively intermediate 81,
• present a large annular chamber 153,
• have a small annular chamber 155 connected to the large chamber 153 and which is open at least locally on the side of the core,
• be in support or fixed against the inside of the crown 3.

This apparatus 151 may comprise in the small annular chamber 155 sensors of different types known in the art to make detections and / or particularly electrical measurements on a core that enters the corer 1. The large annular chamber 153 is intended to receive apparatus for detecting, measuring and / or recording or even transmitting data to the operators, connected to these sensors, not shown.

The particular fluid aforesaid may then be selected and / or arranged to have electrical characteristics matching the operation of these sensors, as is known.

Thus, from the moment a core penetrates the corer and before raising it to the surface, it is possible to carry out one or more measurements and / or detections of parameters of this core at the level of the crown 3 and a recording and / or a transmission to an operator of these measurements and / or detections. These can be exploited to decide the actions to be taken during deviated coring.

The means 11 or guide channel 79 is mainly represented in the form of a tube in a major part of its length. It can however be any shaped element to give the result described.

Legend of figures

1

corer

3

coring crown of 1

5

bore of internal caliber of 2

7

internal guide

9

destructible element

11

guide way

13

means of fixing 9 to the wall

15

annular sleeve

15A

one end of 15

15B

other end of 15

17

expansion means of 10

19

annular chamber of 9

21

fluid supply means 13

23

locking means or valve

24

through holes to 19

25

pin between 3 and 9

25A

thickening of 25

27

nozzle of 3

28

washer on 25

28A

nut on 25

29

posterior end of 7

31

inner tube of 1

33

outer tube of 1

35

posterior end of 9

37

side area of 9

39

longitudinal canal of 7 and 9

41

longitudinal axis of 1

43

interior space of 31

45

piston and piston system

47

upper space 43

49

lower space of 43

51

stopper in a passage in 31

53

annular clearance of 45

55

O-rings on 45

57

transverse passage in 45

59

valve to 49

61

longitudinal passage in 45

63

surplus valve

65

surplus fluid outlet through 45

67

thrust ball system

69

gap between 31 and 33

71

orifices to 69

73

orifice to 45

75

closing ball of 73

77

stabilization wing

79

guide channel

81

intermediate guide tube

83

removable set

84

toothed coupling

85

centering means

86

hooking pin

87

drilling rig

89

string of stems

91

drill head

93

87 engine

95

posterior end of 93

97

removable tube

99

breakable pin

101

transverse sealing tube

103

longitudinal grooves

105

internal growths of 97

106

spring ratchet

107

longitudinal groove

109

posterior end of 1

111

crossings

113

selector piston

115

breakable pin

117

nozzle

119

outer sleeve

121

breakable pin

122

transverse sealing tube

123

shoulder of stop

125

orifices in 89

127

holes

129

space between 33 and 81

131

interior space of 31

133

distribution piston

135

133 valve

137

135 stem

138

ball

139

spring ratchet

141

longitudinal groove in 81

143

pipe

145

79 cap

147

membrane

151

equipment

153

large annular chamber

155

small annular chamber

Claims (16)

1. Method for coring and/or drilling through a wall of a bore hole which has been cored or drilled previously in an underground formation, in order to carry out coring and/or drilling deviated transversely from and with respect to a longitudinal direction of the bore hole, the method being characterised in that it comprises:

   - besides selection of a core barrel (1) provided with a core bit (3) having an inner gauge bore(5),

   - arrangement, in the core barrel (1), of an internal guide (7)

   - which is made of a material resistant to the abrasion of the bit (3),

   - which, before beginning a deviated coring, is inside at least the inner gauge bore (5), so that the bit (3) can move along this internal guide (7),

   - which extends in front of the bit (3), according to a forward direction of coring thereof,

   - detachable fixing to the bit (3), and in front thereof according to its forward direction of coring, of a destructible element (9)

   - which is made of a material chosen so that it can be destroyed by the bit (3) in the process of deviated coring and/or drilling, and

   - which has dimensions chosen in order to go into the bore hole, and

   - in the destructible element (9), fixing of a guidance means (11) arranged to give a deviated path direction to the internal guide extending in front of the bit,

   - start-up of the coring with said bit (3) and

   - guidance of the bit (3) through cooperation between its inner gauge bore (5) and the internal guide (7), with progressive deviation of the bit (3) from said longitudinal direction towards the wall, following said desired deviated path direction, until said wall and the formation are penetrated to a desired depth following the deviated path.
2. Method according to Claim 1, characterised in that it comprises

   - use of the above-mentioned internal guide (7) as the guidance means (11) in the destructible element (9),

   - fixing of the destructible element (9) to the wall of the bore hole at a location chosen for a deviated coring,

   - next, breaking of the detachable fixing between the bit (3) and the destructible element (9), and

   - setting into rotation and pushing forward of the bit (3) in order to follow the deviated path given by the internal guide (7), destroying the part of the destructible element (9) which it encounters and penetrating said wall and the formation to a desired depth.
3. Method according to Claim 1, characterised in that it comprises

   - arrangement, as the guidance means (11) in the destructible element (9), of a guidance channel (79), one end of which is substantially coaxial with the inner gauge bore (5) and whose line corresponds to the desired deviated path,

   - disposition of the internal guide (7) comprising a drilling machine (87), carried by a drilling string (89), through the core barrel (1) and the inner gauge bore (5) and following the guidance channel (79),

   - drilling by the machine (87) in the wall of the bore hole according to said deviated path given by the guidance channel (79), the drilling string (89) having a length chosen in order that, when the drilling machine (87) is driven into the wall according to a chosen anchorage depth, the drilling string (89) is still engaged in at least the inner gauge bore (5) of the bit (3),

   - next, breaking of the detachable fixing between the bit (3) and the destructible element (9), and

   - setting into rotation and pushing forward of the bit (3) following the deviated path given by the drilling string (89) and the drilling machine (87), in order to destroy the part of the destructible element (9) and of said guidance channel (79) which it encounters and to penetrate said wall and the formation to a desired depth.
4. Method according to Claim 1, characterised in that it comprises

   - arrangement, as the guidance means (11) in the destructible element (9), of a guidance channel (79), one end of which is substantially coaxial with the inner gauge bore (5) and whose line corresponds to the desired deviated path,

   - arrangement of the internal guide (7) comprising a drilling machine (87t), carried by a drilling string (89t), through the core barrel (1) and the inner gauge bore (5) and following the guidance channel (79) in the direction of said wall,

   - fixing of the drilling machine (87t) to the core barrel (1), so that it projects by a given distance outside the bit (3) into the guidance channel (79),

   - fixing of the destructible element (9) to said wall of the bore hole,

   - breaking of the detachable fixing between the bit (3) and the destructible element (9),

   - setting into rotation and pushing forward of the bit (3) and the drilling machine (87t),

   - drilling by the machine (87t) in the wall of the bore hole according to said deviated path given by the guidance channel (79),

   - coring by the bit (3) following the deviated path given by the drilling string (89t) and the drilling machine (87t), destroying the part of the destructible element (9) and of said guidance channel (79) which it encounters and penetrating said wall and the formation to a desired depth.
5. Method according to Claim 4, characterised in that it comprises suspension of the pushing and/or rotation of the drilling machine (87t) and continuation of the rotation and pushing forward of the guided bit (3) along the drilling machine (87t) and/or its drilling string (89).
6. Method according to any one of Claims 1 to 5, characterised in that it comprises, from the moment a core enters the core barrel (1) and before raising the latter to the surface, one or more measurements and/or detections of parameters of this core at the level of the bit (3) and recording and/or transmission to an operator of these measurements and/or detections.
7. Device for coring and/or drilling through a wall of a bore hole which has been cored or drilled previously in an underground formation, in order to carry out coring and/or drilling deviated transversely from and with respect to a longitudinal direction of the bore hole, in particular for implementation of the method according to any one of the preceding claims, the device being characterised in that it comprises:

   - a core barrel (1), provided with a core bit (3) having an inner gauge bore (5),

   - an internal guide (7)

   - which is made of a material resistant to the abrasion of the bit (3),

   - which, before beginning a deviated coring, is inside at least the inner gauge bore (5), so that the bit (3) can move along this internal guide (7),

   - which extends in front of the bit (3), according to a forward direction of coring thereof,

   - a destructible element (9) fixed in a detachable manner in front of the bit (3) according to the forward direction of coring thereof,

   - made of a material chosen so that it can be destroyed by the bit (3) in the process of coring and/or drilling along the deviated path,

   - with dimensions chosen in order to go into the bore hole, and

   - in which there is fixed a guidance means (11) arranged to give a deviated path direction to the internal guide extending in front of the bit,

   - the internal guide being, during the deviated coring and/or drilling, kept fixed in order to give to the bit (3) the desired deviation direction, and to progressively deviate the bit (3) from said longitudinal direction towards the wall.
8. Device according to Claim 7, characterised in that the destructible element (9) comprises a means (13) for selective fixing to the wall of the bore hole.
9. Device according to either one of Claims 7 and 8, characterised in that the detachable fixing between the destructible element (9) and the bit (3) is arranged to be detached by relative rotation of the bit (3) with respect to the destructible element (9) fixed to said wall.
10. Device according to Claim 9, characterised in that said detachable fixing comprises at least one rod (25)

    - fixed each time through a nozzle (27) of the bit (3),

    - which is tubular, open at one end turned towards the inside of the bit (3) and as far as beyond the nozzle (27) outside the bit (3), and closed at the other end,

    - breakable between the bit (3) and the destructible element (9), during said rotation, and

    - made of a material that can be removed by coring fluid passing in the broken tubular rod (25) and/or the corresponding nozzle (27).
11. Device according to Claim 8, characterised in that the means (13) for selective fixing to the wall of the bore hole comprise an annular sleeve (15),

    - made of elastic material,

    - mounted on a radial periphery of the destructible element (9),

    - whose external diameter can be expanded selectively until it becomes wedged against the wall of the bore hole, means being provided to cause the expansion and retain it.
12. Device according to Claim 11, characterised in that the means for causing an expansion comprise an annular chamber (19) between the sleeve (15) and the destructible element (9) and means (21) for supplying this chamber with fluid, as well as blocking-up means (23) arranged to selectively block up in the annular chamber (19) the fluid which has been supplied thereto.
13. Device according to any one of Claims 7 to 12, characterised in that said guidance means (11) is the aforementioned internal guide (7) fixed in the destructible element (9).
14. Device according to any one of Claims 7 to 12, characterised in that

    - said guidance means (11) in the destructible element (9) is a guidance channel (79), one end of which is substantially coaxial with the inner gauge bore (5) of the bit (3) and whose line corresponds to the desired deviated path,

    - the above-mentioned internal guide (7) comprises a drilling machine (87) carried by a drilling string (89), and is arranged in order to be conveyed through the core barrel (1) and the inner gauge bore (5) and, following the guidance channel (79), to drill and penetrate the wall of the bore hole according to said deviated path given by the guidance channel (79), the drilling string (89) having a length chosen in order that, when the drilling machine (87) is driven into the wall according to an anchorage depth, the drilling string (89) is still engaged in at least the inner gauge bore (5) of the bit (3).
15. Device according to any one of Claims 8 to 12, characterised in that

    - said guidance means (11), in the destructible element (9), is a guidance channel (79), one end of which is substantially coaxial with the inner gauge bore (5) of the bit (3), and whose line corresponds to the desired deviated path,

    - the internal guide (7) comprises a drilling machine (87t), carried by a drilling string (89t), arranged through the core barrel (1) and the inner gauge bore (5) and following the guidance channel (79) in the direction of said wall,

    - the drilling machine (87t) and its drilling string (89t) are mounted in the core barrel (1) so that said machine (87t) projects by a given distance outside the bit (3) into the guidance channel (79), a means being provided to keep this distance fixed at least temporarily.
16. Device according to Claim 15, characterised in that, for its rotational driving, the drill head (91t) of the drilling machine (87t) is coupled by its drilling string (89t) to the bit (3) of the core barrel (1).

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