EP0055675B1 - Method and apparatus for determining the stuck point of drill pipes in a borehole - Google Patents

Method and apparatus for determining the stuck point of drill pipes in a borehole Download PDF

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Publication number
EP0055675B1
EP0055675B1 EP81402090A EP81402090A EP0055675B1 EP 0055675 B1 EP0055675 B1 EP 0055675B1 EP 81402090 A EP81402090 A EP 81402090A EP 81402090 A EP81402090 A EP 81402090A EP 0055675 B1 EP0055675 B1 EP 0055675B1
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EP
European Patent Office
Prior art keywords
parts
detecting
anchoring
conduit
movements
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
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EP81402090A
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German (de)
French (fr)
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EP0055675A1 (en
Inventor
Jean-Michel Hache
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Services Petroliers Schlumberger SA
Schlumberger NV
Schlumberger Ltd USA
Original Assignee
Societe de Prospection Electrique Schlumberger SA
Schlumberger NV
Schlumberger Ltd USA
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Application filed by Societe de Prospection Electrique Schlumberger SA, Schlumberger NV, Schlumberger Ltd USA filed Critical Societe de Prospection Electrique Schlumberger SA
Publication of EP0055675A1 publication Critical patent/EP0055675A1/en
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Publication of EP0055675B1 publication Critical patent/EP0055675B1/en
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    • E—FIXED CONSTRUCTIONS
    • E21—EARTH DRILLING; MINING
    • E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B47/00—Survey of boreholes or wells
    • E21B47/09—Locating or determining the position of objects in boreholes or wells, e.g. the position of an extending arm; Identifying the free or blocked portions of pipes

Definitions

  • the invention relates to methods and devices used in soundings, for detecting the point of jamming of a column of rods in a sounding.
  • a conventional method for determining the depth of the pinch point is to apply twists and pulls to the column on the surface, and determine to what depth these deformations are transmitted.
  • a device is used which is lowered into the column at the end of a cable and placed at successive depths.
  • a conventional sticking point detection device described for example in US Patent No. 3,686,943 to WD Smith, comprises a body having an upper part and a lower part mounted so that they can be moved one by one. compared to each other. Upper and lower anchoring members mounted respectively on these upper and lower parts immobilize each of the body parts in two zones longitudinally spaced from the column. Electric motors controlled by the cable are used to separate and bring the anchoring members closer to the body. Detection means, mounted between the parts of the body, measure the relative movements between these parts when the column is elastically deformed by stresses applied on the surface.
  • An improved anchoring process described in U.S. Patent No. 4,104,911 (J.C. Lavigne and Y. Nicolas), involves first anchoring the upper part of the body. The lower part is then anchored after having released the cable tension.
  • the advantage of this process is that it does not compress the moving parts of the body for measurement. During this measurement, however, it is necessary that the two parts of the body be longitudinally in the contracted position in order to be able to move away from each other when applying pulls to the column of rods.
  • the apparatus generally comprises an elastic member or spring which applies a restoring force to the parts of the body to urge them towards each other.
  • This restoring force is opposed to the relative longitudinal movements between the two parts of the body during detection.
  • a first object of the invention is to minimize such a longitudinal restoring force during the measurement.
  • the apparatus For the detection of movements between the parts of the body, it is advantageous to use a sensor described in the prior French patent No. 24 81 737 and EP-A-39 278 (inventor P. Moutin), which provides two output signals, one independent of rotations and the other independent of longitudinal displacements between parts of the body.
  • the apparatus then comprises a reset system for placing the detection means in an initial angular position before the measurement. A complicated sequence of operations is necessary to order this reset.
  • the angular reset system comprises a spring, or any other elastic means, the restoring torque of which prevents rotation between the two parts of the body during detection.
  • a second object of the invention is to provide an automatic angular reset system that does not exhibit a restoring torque during the measurement.
  • a usual reset system is generally driven by a motor member which is specific to it and controlled separately.
  • Another object of the invention is a device, the resetting of which takes place automatically after anchoring of the lower part of the body.
  • the restoring force is applied beforehand between the second part of the body and a movable member coupled, before the anchoring step, to the first part of the body but disconnectable from the latter. After the anchoring step, this member is decoupled from the first part of the body to decouple the restoring force from the first part.
  • a device for detecting the point of jamming of the rods in a borehole comprises a body adapted to be suspended from a cable and having two parts mounted movable relative to each other. Each part can be anchored inside the rods by a surface control and means detect the relative movements between said parts when the rods are deformed by applying them on the surface of the constraints. Return means are provided to apply to the body parts a longitudinal return force which biases them towards each other.
  • a device of this type is already known from US-A-41 04911.
  • disconnectable connecting means which connect the return means to a first of said body parts are decoupled by motor means after anchoring of the two parts inside the rods in order to suppress the application of the restoring force between said parts during detection.
  • the connecting means preferably comprise a member mounted movable between a first position connected to the first part of the body and a second position decoupled from the first part.
  • the return means are arranged between the second part and this member to urge this member towards the first position and then apply the return force to the first part of the body.
  • the drive means arranged in the second part of the body, move the movable member to the second position to decouple this member from the first part.
  • the movable member is preferably blocked relative to the second part of the body in the second position and decoupled from this second part in the first position.
  • the detection means are arranged on this member and the first part of the body to be sensitive to angular movements between this member and the second part.
  • Reset means place the movable member relative to the first part of the body when this member is in the first position so that the angular detection means are substantially at zero.
  • the reset means comprise oblique ramps for placing the sleeve in the zero position under the action of the return means.
  • Longitudinal movement detection means are preferably arranged on said movable member and the first part of the body to detect longitudinal extension movements between this first part and this member.
  • the drive means are adapted to anchor the lower part of the body in the rods before moving the sleeve towards the second position.
  • a jamming point detection device comprises a bottom device 10 suspended in a column of rods 11 at the end of a cable 12.
  • the rods 11 disposed in a borehole 13 are trapped by the terrain formations at a point 14 whose depth is to be determined.
  • the rods are suspended on the surface in a known manner from a drilling tower (not shown) equipped with mechanisms making it possible to apply tensile and torsional forces to these rods.
  • the cable 12 comprises one or more electrical conductors connected to a surface device 15. This device is suitable for sending an electrical supply current and electrical control signals to the downhole device and for receiving the signals coming from this device. to process, display and save them.
  • the downhole apparatus 10 generally comprises an electronic section 20 formed by a sealed envelope containing electronic circuits, and a mechanical section 21. At the bottom of the mechanical section is fixed a support 22 adapted to receive an explosive as for example several lengths of detonating cord intended to be ignited at a selected joint of the rods. The purpose of this explosion is to unscrew all of the rods located above the joint selected during an operation called "back off" by specialists.
  • the mechanical section 21 comprises a body produced in two parts 23 and 24 mounted movable relative to one another with limited displacements longitudinally and angularly. Each part is equipped with several anchoring arms such as 25 for the upper part and 26 for the lower part. The anchoring arms are articulated on the body and can be moved apart by a surface control to come to anchor inside the rods.
  • the mechanical section is shown in more detail in Figures 2A and 2B.
  • the sealed envelope 30 of the electronic section is fixed by a threaded ring 31 to the upper part 23 of the body.
  • the electrical connections between the electronic and mechanical sections are provided by plug-in connectors 32 which pass through a sealed and isolated head 33 fixed in the upper part 23 of the body.
  • a first chamber 35 below the head 33 is made inside the upper part 23 of the body.
  • the chamber 35 is filled with a hydraulic fluid maintained substantially at the prssion of the borehole as will be seen later.
  • a bore 36 in which is slidably mounted an actuating rod 37 fitted with an O-ring 38.
  • the part 23 of the body carries cutouts 40 adapted to receive three arms d anchor 25 mounted to rotate about pivots 41.
  • On each anchoring arm is mounted rotating a pin 42 which engages in a transverse groove of the actuating rod 37 so that a longitudinal movement of this rod rotates the arms around pivots 41.
  • the actuating rod 37 crosses at its lower part a longitudinal bore 43 produced in part 23 of the body.
  • An O-ring 44 mounted on this rod, seals this crossing.
  • the rod 37 thus enters a second chamber 45 which communicates with the first 35 via a longitudinal passage 46 produced in the axis of the rod 37.
  • a housing 46 which contains motor members for longitudinally moving the actuating rod 37.
  • an assembly 50 formed by an alternating current motor and a reduction gear.
  • the gear unit output shaft is connected by an Oldham seal 51 to a ball bearing 52 and then to a ball screw 53.
  • the nut element of the ball screw 53 is fixed to the enlarged lower end of the actuating rod 37.
  • the chamber 45 communicates with the interior of the housing through a passage 54, so that the free spaces are occupied by hydraulic fluid which bathes the motor 50, the stop 52 and the ball screw 53. Passages are provided between the housing 47 and the body to allow the wiring of the electrical conductors from the connectors 32 to the bottom of the chamber 45.
  • the body comprises an axial tube 54 the interior of which communicates with the chamber 45.
  • the body also has a cylindrical wall 55 around the tube 54 so as to delimit an annular chamber 56 in which a floating piston 57 slides, pressure equalizer.
  • the annular chamber 56 filled with hydraulic fluid, communicates with the interior of the tube 54 by a passage 60.
  • the underside of the piston 57 is in contact with the probing fluids by a passage 61.
  • the seal between the piston and the tube 54 is produced by a seal 62 and that between the piston and the cylindrical wall 55 by a seal 63.
  • the upper part 23 of the body extends downwards, below the annular chamber 56, by a mandrel 65 which penetrates into the lower part 24 of the body.
  • a seal 66 seals between this lower part 24 and an annular end 67 of the upper part 23.
  • the lower part 24 of the body can move away and rotate relative to the annular end 67 at the level of the shoulder 59 In the lower part 24.
  • a sleeve 70 is movably mounted between a high position (FIG. 2B) and a low position (FIG. 4).
  • the mandrel 65 is pierced with an axial channel 68 which places the chamber 45 in communication with the interior of the tube 54 with another chamber 69 produced in the lower part of the body.
  • Channel 68 also serves as a passage for electrical conductors.
  • FIG. 2B is a section along line 5-5 of FIG. 3.
  • diametrically opposed lugs 72 having two sides parallel to the longitudinal direction and a upper edge in an inverted V shape.
  • windows 73 having oblique ramps at their upper part.
  • the pins 72 are placed in the windows 73, the dimensions of which are chosen to allow, in the upper position of the sleeve, limited movements longitudinally and angularly, of the mandrel 65 relative to the sleeve 70.
  • the upper edges of the pins 78 and windows 73 form ramps which immobilize the sleeve 70 downwards in a first position angularly corresponding to the zero of the angular detection means.
  • the sleeve has an upper part of smaller diameter around which is placed a helical spring 74 mounted in compression between this sleeve and a shoulder 75 of the lower part of the body.
  • a helical spring 74 mounted in compression between this sleeve and a shoulder 75 of the lower part of the body.
  • the apparatus includes means for detecting longitudinal and angular movements between the sleeve and the mandrel.
  • These detection means include two differential transformers.
  • a first transformer with axial coils comprises a primary 80 fixed to the mandrel and a secondary formed by two coils 81 and 82 fixed to the sleeve. This first transformer detects longitudinal movements between parts of the body while being insensitive to angular movements.
  • a second transformer with radial coils comprising a primary 83 fixed to the mandrel and a secondary formed by two coils 84 and 85 fixed to the sleeve, detects angular movements but is insensitive to longitudinal movements between the parts of the body.
  • the primary 80 of the first transformer is centered between the two coils 81 and 82 of the secondary as shown in FIG. 2B.
  • the primary 83 of the second transformer has its axis perpendicular to that of the coils 84 and 85 of the secondary.
  • the sleeve and the mandrel are placed before the measurement in this initial position by the interaction of the pins 72 and the windows 73.
  • a housing 86 containing driving members is slidably mounted in the lower part 24 of the body below the sleeve 70.
  • the interior of the housing communicates with the chamber 69 through a passage 88.
  • an assembly 87 constituted by a alternating current electric motor and a reducer.
  • the output shaft 90 of the reducer mounted rotatably in the housing by a ball bearing 91, is connected to the threaded shaft of a ball screw 92.
  • the nut member of the ball screw 92 is fixed to a actuating rod 93 which leaves the housing 86 and passes through a transverse partition 94 of the body closing down the chamber 69 filled with hydraulic fluid.
  • the seal between the actuating rod 93 and the transverse partition 94 is ensured by a seal 95.
  • the body has cutouts 96 in which are arranged three anchoring arms 26 articulated on pivots 97.
  • the actuating rod 93 passes through a bore 100 made in the axis of the body to open into a chamber 101.
  • a seal 102 seals between the rod 93 and the body.
  • the actuating rod has a triangular cross section with three transverse grooves 103.
  • On each anchoring arm 26 is mounted rotating a pin 104 having a projecting rib which engages in one of the grooves 103.
  • the motor-reduction unit can be supplied with electric current so as to move the actuating rod 93, either downwards or upwards, relative to the housing 86.
  • a longitudinal channel 105 cut out in the actuating rod 98 communicates the chamber 69 with the chamber 101.
  • An electrical conductor placed in the channel 105 is connected to a connector 106 mounted in an isolated and sealed manner at the bottom of the lower part 24 of the body. On this end is fixed by screws 107 the upper part 108 of the support 22 of explosives.
  • An electric detonator (not shown) for igniting this explosive is connected to connector 106.
  • the bottom device 10 To perform a jamming point measurement, first connect the bottom device 10 to the cable 12 in order to lower it into the rods 11.
  • the upper 25 and lower 26 anchoring arms are closed and the various members contained. in the lower part of the body are in the position shown in FIG. 4.
  • the housing 86 In particular, the housing 86 is in bottom abutment against the transverse partition 94.
  • the actuating rod 93 in the high position in the housing 86, keeps the lower anchoring arm 26.
  • the sleeve 70 pushed back by the spring 74, is in the low position, immobilized by the pins 72 which bear on the top of the windows 73.
  • the angular motion detector formed by the coils 83, 84 and 85 is thus placed in its angular position of zero.
  • the spring 74 also applies to the lower part of the body an ascending restoring force which maintains the two parts 23 and 24 in the retracted position.
  • the apparatus 10 is then lowered into the borehole to a first depth where it is desired to determine whether the rods are free.
  • the motor 50 is supplied with current (FIG. 2A), so as to separate the upper anchoring arms 25.
  • the motor 50 After anchoring of the upper part of the body 23 and after having released the tension of the cable 12, running the motor 87.
  • the lower anchoring arms move away from the body until they bear against the internal wall of the rods 11.
  • the housing 86 rises slightly in the lower part of the body until it comes to bear on the bottom of the sleeve 70.
  • the lateral force of application of the anchoring arms 26 is determined by the longitudinal return force of the spring 24, transmitted by the sleeve 70 and the housing 86 to the actuating rod 93.
  • the anchoring arm 26 having reached their maximum spacing in the rods, stop the movement of the actuating rod 93 relative to the lower part 24 of the body.
  • the housing 86 moves upward, causing the sleeve 70 which compresses the spring 74. This movement continues until the upper end of the sleeve 70 comes to bear against the shoulder 75. The sleeve 70 is then locked in the high position in the lower part 24 of the body. During this movement, the oblique contact surfaces of the windows and the pins move away from each other, which decouples the connection between the sleeve 70 and the mandrel 65. With respect to the mandrel 65, the sleeve 70, blocked at this instant in the lower part 24 of the body, is free to move with limited movements angularly to the right or to the left and longitudinally in extension.
  • FIG. 2B This upper position of the sleeve, for which the angular and longitudinal detection means are substantially at zero, is shown in FIG. 2B.
  • the device is then ready to carry out a measurement, that is to say to detect movements between the parts of the body when tensile or torsional stresses are applied to the rods at the surface.
  • the motors 87 and 50 are supplied with current to close the upper and lower anchoring arms.
  • the bottom device can then be moved using the cable 12 to carry out other measurements at different depths.
  • the sleeve 70 is held on the mandrel 65 in a low position for which the angular movement detector is substantially at zero.
  • the longitudinal movement detector indicates a maximum elongation.
  • the coil 80 is offset upwards by a distance d from the midpoint of the coils 81 and 82.
  • the sleeve 70 After anchoring of the two parts of the body, the sleeve 70 is brought, relative to the mandrel, in its high position which, angularly, is not modified from the previous low position. For this position, the longitudinal movement detector is substantially at zero. From this position, the sleeve 70 secured to the lower part of the body is decoupled from the upper part. Any restoring force tending to oppose longitudinal or angular movements between the parts of the body is eliminated during the measurement. In addition, the indication provided by the longitudinal movement detector when the device is anchored can be followed on the surface to ensure that it functions properly.
  • the detection means can be produced in a form different from the electromagnetic sensor described above.

Description

L'invention se rapporte aux procédés et dispositifs utilisés dans les sondages, pour détecter le point de coincement d'une colonne de tiges dans un sondage.The invention relates to methods and devices used in soundings, for detecting the point of jamming of a column of rods in a sounding.

Lorsqu'une colonne de tiges, comme par exemple un train de tiges de forage, est coincée dans un sondage, un procédé classique pour déterminer la profondeur du point de coincement consiste à appliquer à la colonne en surface des torsions et des tractions, et à déterminer jusqu'à quelle profondeur se transmettent ces déformations. Pour détecter ces déformations, on utilise un appareil descendu dans la colonne à l'extrémité d'un câble et mis en place à des profondeurs successives.When a column of rods, such as a drill string, is stuck in a borehole, a conventional method for determining the depth of the pinch point is to apply twists and pulls to the column on the surface, and determine to what depth these deformations are transmitted. To detect these deformations, a device is used which is lowered into the column at the end of a cable and placed at successive depths.

Un appareil classique de détection de point de coincement, décrit par exemple dans le brevet des Etats-Unis d'Amérique No. 3 686 943 accordé à W.D. Smith, comprend un corps ayant une partie supérieure et une partie inférieure montées mobiles l'une par rapport à l'autre. Des organes d'ancrage supérieurs et inférieurs montés respectivement sur ces parties supérieure et inférieure immobilisent chacune des parties du corps en deux zones longitudinalement espacées de la colonne. Des moteurs électriques commandés par l'intermédiaire du câble servent à écarter et rapprocher du corps les organes d'ancrage. Des moyens de détection, montés entre les parties du corps, mesurent les mouvements relatifs entre ces paries lorsqu'on déforme élastiquement la colonne par des contraintes appliquées en surface.A conventional sticking point detection device, described for example in US Patent No. 3,686,943 to WD Smith, comprises a body having an upper part and a lower part mounted so that they can be moved one by one. compared to each other. Upper and lower anchoring members mounted respectively on these upper and lower parts immobilize each of the body parts in two zones longitudinally spaced from the column. Electric motors controlled by the cable are used to separate and bring the anchoring members closer to the body. Detection means, mounted between the parts of the body, measure the relative movements between these parts when the column is elastically deformed by stresses applied on the surface.

Un procédé d'ancrage perfectioné, décrit dans le brevet des Etats-Unis d'Amérique No. 4104 911 (J.C. Lavigne et Y. Nicolas), consiste à ancrer tout d'abord la partie supérieure du corps. On ancre ensuite la partie inférieure, après avoir relâché la tension du câble. L'avantage de ce processus est de ne pas mettre en compression les parties mobiles du corps pour la mesure. Pendant cette mesure, il est nécessaire toutefois que les deux parties du corps soient longitudinalement en position contractée pour pouvoir s'éloigner l'une de l'autre lorsqu'on applique des tractions à la colonne dé tiges. Dans ce but, l'appareil comprend généralement un organe élastique ou ressort qui applique une force de rappel aux parties du corps pour les solliciter l'une vers l'autre. L'inconvénient des appareils connus est que cette force de rappel s'oppose aux déplacements longitudinaux relatifs entre les deux parties du corps pendant la détection.An improved anchoring process, described in U.S. Patent No. 4,104,911 (J.C. Lavigne and Y. Nicolas), involves first anchoring the upper part of the body. The lower part is then anchored after having released the cable tension. The advantage of this process is that it does not compress the moving parts of the body for measurement. During this measurement, however, it is necessary that the two parts of the body be longitudinally in the contracted position in order to be able to move away from each other when applying pulls to the column of rods. For this purpose, the apparatus generally comprises an elastic member or spring which applies a restoring force to the parts of the body to urge them towards each other. The disadvantage of known devices is that this restoring force is opposed to the relative longitudinal movements between the two parts of the body during detection.

Un premier objet de l'invention est de minimiser une telle force de rappel longitudinale pendant la mesure.A first object of the invention is to minimize such a longitudinal restoring force during the measurement.

Pour la détection des mouvements entre les parties du corps, il est intéressant d'utiliser un capteur décrit dans le brevet français autérieur No. 24 81 737 et la EP-A-39 278 (inventeur P.Mou- tin), qui fournit deux signaux de sortie l'un indépendant des rotations et l'autre indépendant des déplacements longitudinaux entre les parties du corps. L'appareil comprend alors un système de remise à zéro pour placer les moyens de détection dans une position angulaire initiale avant la mesure. Une suite compliquée d'opérations est nécessaire pour commander cette remise à zéro. Dans d'autres appareils connus, le système de remise à zéro angulaire comprend un ressort, ou tout autre moyen élastique, dont le couple de rappel s'oppose aux rotations entre les deux parties du corps pendant la détection.For the detection of movements between the parts of the body, it is advantageous to use a sensor described in the prior French patent No. 24 81 737 and EP-A-39 278 (inventor P. Moutin), which provides two output signals, one independent of rotations and the other independent of longitudinal displacements between parts of the body. The apparatus then comprises a reset system for placing the detection means in an initial angular position before the measurement. A complicated sequence of operations is necessary to order this reset. In other known devices, the angular reset system comprises a spring, or any other elastic means, the restoring torque of which prevents rotation between the two parts of the body during detection.

Un deuxième objet de l'invention est de réaliser un système automatique de remise à zéro angulaire ne présentant pas de couple de rappel pendant la mesure.A second object of the invention is to provide an automatic angular reset system that does not exhibit a restoring torque during the measurement.

Enfin un système de remise à zéro usuel est généralement entraïné par un organe moteur qui lui est propre et commandé de façon distincte.Finally, a usual reset system is generally driven by a motor member which is specific to it and controlled separately.

Un autre objet de l'invention est un dispositif dont la remise à zéro s'effectue automatiquement après ancrage de la partie inférieure du corps.Another object of the invention is a device, the resetting of which takes place automatically after anchoring of the lower part of the body.

Selon un aspect de l'invention, un procédé pour détecter le point de coincement des tiges dans un sondage comprend les étapes suivantes:

  • - descendre dans les tiges un dispositif comprenant un corps en deux parties montées mobiles l'une par rapport à l'autre et normalement sollicitées l'une vers l'autre par une force de rappel;
  • - ancrer chacune desdites parties à l'intérieur des tiges par une commande de surface; et
  • - détecter, par des moyens de détection, les mouvements relatifs entre lesdites parties lorsqu'on déforme les tiges en leur appliquant des contraintes en surface. Ce procédé connu du US-A-41 04 911 comprend selon l'invention de plus l'étape consistant à découpler la force de rappel de la première desdites parties du corps après l'étape d'ancrage et avant l'étape de détection afin de supprimer l'application de cette force entre lesdites parties pendant la détection.
According to one aspect of the invention, a method for detecting the point of jamming of the rods in a borehole comprises the following steps:
  • - descend into the rods a device comprising a body in two parts mounted movable relative to one another and normally biased towards one another by a restoring force;
  • - anchoring each of said parts inside the rods by a surface control; and
  • - Detecting, by detection means, the relative movements between said parts when the rods are deformed by applying surface stresses to them. This method known from US-A-41 04 911 according to the invention further comprises the step of decoupling the restoring force from the first of said body parts after the anchoring step and before the detection step in order to to suppress the application of this force between said parts during detection.

La force de rappel est prétérablement appliquée entre la deuxième partie du corps et un organe mobile couplé, avant l'étape d'ancrage, à la première partie du corps mais déconnectable de cette dernière. Après l'étape d'ancrage, cet organe est découplé de la première partie du corps pour découpler la force de rappel de la première partie.The restoring force is applied beforehand between the second part of the body and a movable member coupled, before the anchoring step, to the first part of the body but disconnectable from the latter. After the anchoring step, this member is decoupled from the first part of the body to decouple the restoring force from the first part.

Le procédé comprend préférablement de plus les étapes suivantes:

  • - avant l'étape d'ancrage, maintenir, dans une position de zéro les moyens de détection angulaires découplés d'une deuxième desdites parties du corps; et
  • - coupler les moyens de détection angulaires à ladite deuxième partie après l'étape d'ancrage et avant l'étape de détection sans changer sensiblement la position de zéro desdits moyens de détection.
The method preferably further comprises the following steps:
  • - before the anchoring step, maintain, in a position of zero, the angular detection means decoupled from a second of said parts of the body; and
  • - Coupling the angular detection means to said second part after the anchoring step and before the detection step without substantially changing the zero position of said detection means.

Selon un autre aspect de l'invention, un dispositif pour détecter le point de coincement des tiges dans un sondage, comprend un corps adapté à être suspendu à un câble et ayant deux parties montées mobiles l'une par rapport à l'autre. Chaque partie peut être ancrée à l'intérieur des tiges par une commande de surface et des moyens détectent les mouvements relatifs entre lesdites parties lorsqu'on déforme les tiges en leur appliquant en surface des contraintes. Des moyens de rappel sont prévus pour appliquer aux parties du corps une force de rappel longitudinale qui les sollicite l'une vers l'autre. Un dispositif de ce type est déjà connu du US-A-41 04911. Selon l'invention, des moyens de liaison déconnectables qui relient les moyens de rappel à une première desdites parties du corps sont découplés par des moyens moteurs après ancrage des deux parties à l'intérieur des tiges afin de supprimer l'application de la force de rappel entre lesdites parties pendant la détection.According to another aspect of the invention, a device for detecting the point of jamming of the rods in a borehole, comprises a body adapted to be suspended from a cable and having two parts mounted movable relative to each other. Each part can be anchored inside the rods by a surface control and means detect the relative movements between said parts when the rods are deformed by applying them on the surface of the constraints. Return means are provided to apply to the body parts a longitudinal return force which biases them towards each other. A device of this type is already known from US-A-41 04911. According to the invention, disconnectable connecting means which connect the return means to a first of said body parts are decoupled by motor means after anchoring of the two parts inside the rods in order to suppress the application of the restoring force between said parts during detection.

Les moyens de liaison comprennent préférablement un organe monté mobile entre une première position reliée à la première partie du corps et une deuxième postition découplée de la première partie. Les moyens de rappel sont disposés entre la deuxième partie et cet organe pour solliciter cet organe vers la première position et appliquer alors la force de rappel à la première partie du corps. Les moyens moteurs, disposés dans la deuxième partie du corps, déplacent l'organe mobile vers la deuxième position pour découpler cet organe de la première partie.The connecting means preferably comprise a member mounted movable between a first position connected to the first part of the body and a second position decoupled from the first part. The return means are arranged between the second part and this member to urge this member towards the first position and then apply the return force to the first part of the body. The drive means, arranged in the second part of the body, move the movable member to the second position to decouple this member from the first part.

L'organe mobile est préférablement bloqué par rapport à la deuxième partie du corps dans la deuxième position et découplé de cette deuxième partie dans la première position. Les moyens de détection sont disposés sur cet organe et la première partie du corps pour être sensibles aux mouvements angulaires entre cet organe et la deuxième partie. Des moyens de remise à zéro placent l'organe mobile par rapport à la première partie du corps lorsque cet organe est dans la première position de façon que les moyens de détection angulaires soient sensiblement au zéro. Les moyens de remise à zéro comprennent des rampes obliques pour placer le manchon en position de zéro sous l'action des moyens de rappel.The movable member is preferably blocked relative to the second part of the body in the second position and decoupled from this second part in the first position. The detection means are arranged on this member and the first part of the body to be sensitive to angular movements between this member and the second part. Reset means place the movable member relative to the first part of the body when this member is in the first position so that the angular detection means are substantially at zero. The reset means comprise oblique ramps for placing the sleeve in the zero position under the action of the return means.

Des moyens de détection de mouvements longitudinaux sont de préférance disposés sur ledit organe mobile et la première partie du corps pour détecter les mouvements longitudinaux d'extension entre cette première partie et cet organe. Les moyens moteurs sont adaptés à ancrer la partie inférieure du corps dans les tiges avant de déplacer le manchon vers la deuxième position.Longitudinal movement detection means are preferably arranged on said movable member and the first part of the body to detect longitudinal extension movements between this first part and this member. The drive means are adapted to anchor the lower part of the body in the rods before moving the sleeve towards the second position.

Autres caractéristiques et les avantages de l'invention ressortiront d'ailleurs mieux de la description qui va suivre donnée à titre d'exemple non limitatif en référence aux dessins annexés dans lesquels:

  • - la figure 1 est une vue en cours d'opération, d'un dispositif selon l'invention pour détecter le point de coincement d'une colonne de tiges dans un sondage;
  • - les figures 2A et 2B sont des coupes longitudinales de l'appareil de fond de la figure 1;
  • - la figure 3 est une coupe transversale selon la ligne 3-3 de la figure 2B; et
  • - la figure 4 est une coupe longitudinale similaire à celle de la figure 2B mais dans laquelle les organes internes sont en position de descente dans le sondage.
Other characteristics and advantages of the invention will emerge more clearly from the description which follows, given by way of nonlimiting example with reference to the appended drawings in which:
  • - Figure 1 is a view during operation, of a device according to the invention for detecting the point of jamming of a column of rods in a borehole;
  • - Figures 2A and 2B are longitudinal sections of the bottom apparatus of Figure 1;
  • - Figure 3 is a cross section along line 3-3 of Figure 2B; and
  • - Figure 4 is a longitudinal section similar to that of Figure 2B but in which the internal organs are in the lowering position in the borehole.

En référence à la figure 1, un dispositif de détection de point de coincement comprend un appareil de fond 10 suspendu dans une colonne de tiges 11 à l'extrémité d'un câble 12. Les tiges 11 disposées dans un sondage 13 sont coincées par les formations de terrain en un point 14 dont on désire déterminer la profondeur. Les tiges sont suspendues en surface d'une façon connue à une tour de forage (non représentée) équipée de mécanismes permettant d'appliquer à ces tiges des efforts de traction et de torsion. Le câble 12 comporte un ou plusieurs conducteurs électriques reliés à un appareillage de surface 15. Cet appareillage est adapté à envoyer vers l'appareil de fond un courant électrique d'alimentation et des signaux électriques de commande et à recevoir les signaux provenant de cet appareil pour les traiter, les afficher et les enregistrer.Referring to Figure 1, a jamming point detection device comprises a bottom device 10 suspended in a column of rods 11 at the end of a cable 12. The rods 11 disposed in a borehole 13 are trapped by the terrain formations at a point 14 whose depth is to be determined. The rods are suspended on the surface in a known manner from a drilling tower (not shown) equipped with mechanisms making it possible to apply tensile and torsional forces to these rods. The cable 12 comprises one or more electrical conductors connected to a surface device 15. This device is suitable for sending an electrical supply current and electrical control signals to the downhole device and for receiving the signals coming from this device. to process, display and save them.

L'appareil de fond 10 comprend d'une façon générale une section électronique 20 formée par une enveloppe étanche contenant des circuits électroniques, et une section mécanique 21. A la partie inférieure de la section mécanique est fixé un support 22 adapté à recevoir un explosif comme par exemple plusieurs longueurs de cordeau détonant destinées à être mises à feu au niveau d'un joint sélectionné des tiges. Cette explosion a pour objet de dévisser l'ensemble des tiges situées au-dessus du joint sélectionné au cours d'une opération appelée «back off» par les spécialistes.The downhole apparatus 10 generally comprises an electronic section 20 formed by a sealed envelope containing electronic circuits, and a mechanical section 21. At the bottom of the mechanical section is fixed a support 22 adapted to receive an explosive as for example several lengths of detonating cord intended to be ignited at a selected joint of the rods. The purpose of this explosion is to unscrew all of the rods located above the joint selected during an operation called "back off" by specialists.

La section mécanique 21 comprend un corps réalisé en deux parties 23 et 24 montées mobiles l'une par rapport à l'autre avec des déplacements limités longitudinalement et angulairement. Chaque partie est équipée de plusieurs bras d'ancrage tels que 25 pour la partie supérieure et 26 pour la partie inférieure. Les bras d'ancrage sont articulés sur le corps et peuvent être écartés par une commande de surface pour venir s'ancrer à l'intérieur des tiges.The mechanical section 21 comprises a body produced in two parts 23 and 24 mounted movable relative to one another with limited displacements longitudinally and angularly. Each part is equipped with several anchoring arms such as 25 for the upper part and 26 for the lower part. The anchoring arms are articulated on the body and can be moved apart by a surface control to come to anchor inside the rods.

La section mécanique est représentée plus en détail sur les figures 2A et 2B. L'enveloppe étanche 30 de la section électronique est fixée par une bague filetée 31 à la partie supérieure 23 du corps. Les liaisons électriques entre les sections électronique et mécanique sont assurées par des connecteurs enfichables 32 qui traversent de façon étanche et isolée une tête 33 fixée dans la partie supérieure 23 du corps. A l'intérieur de la partie supérieure 23 du corps est réalisée une première chambre 35 en dessous de la tête 33. La chambre 35 est remplie d'un fluide hydraulique maintenu sensiblement à la prssion du sondage comme on le verra par la suite.The mechanical section is shown in more detail in Figures 2A and 2B. The sealed envelope 30 of the electronic section is fixed by a threaded ring 31 to the upper part 23 of the body. The electrical connections between the electronic and mechanical sections are provided by plug-in connectors 32 which pass through a sealed and isolated head 33 fixed in the upper part 23 of the body. Inside the upper part 23 of the body is made a first chamber 35 below the head 33. The chamber 35 is filled with a hydraulic fluid maintained substantially at the prssion of the borehole as will be seen later.

A la partie inférieure de la chambre 35 est réalisé un alésage 36 dans lequel est monté coulissante de façon étanche une tige d'actionnement 37 équipée d'un joint torique 38. La partie 23 du corps porte des découpes 40 adaptées à recevoir trois bras d'ancrage 25 montés tournants autour de pivots 41. Sur chaque bras d'ancrage est monté tournant un pion 42 qui s'engage dans une rainure transversale de la tige d'actionnement 37 de façon qu'un mouvement longitudinal de cette tige fasse tourner les bras autour des pivots 41. La tige d'actionnement 37 traverse à sa partie inférieure un alésage longitudinal 43 réalisé dans la partie 23 du corps. Un joint torique 44, monté sur cette tige, assure l'étanchéité de cette traversée. La tige 37 pénètre ainsi dans une deuxième chambre 45 qui communique avec la première 35 par un passage longitudinal 46 réalisé dans l'axe de la tige 37.At the lower part of the chamber 35 is produced a bore 36 in which is slidably mounted an actuating rod 37 fitted with an O-ring 38. The part 23 of the body carries cutouts 40 adapted to receive three arms d anchor 25 mounted to rotate about pivots 41. On each anchoring arm is mounted rotating a pin 42 which engages in a transverse groove of the actuating rod 37 so that a longitudinal movement of this rod rotates the arms around pivots 41. The actuating rod 37 crosses at its lower part a longitudinal bore 43 produced in part 23 of the body. An O-ring 44, mounted on this rod, seals this crossing. The rod 37 thus enters a second chamber 45 which communicates with the first 35 via a longitudinal passage 46 produced in the axis of the rod 37.

Dans la deuxième chambre 45, est placé un boîtier 46 qui contient des organes moteurs pour déplacer longitudinalement la tige d'actionnement 37. A la partie inférieure du boîtier 47 est fixé un ensemble 50 formé par un moteur à courant alternatif et un réducteur. L'arbre de sortie du réducteur est relié par un joint d'Oldham 51 à une butée à billes 52 puis à une vis à billes 53. L'élément écrou de la vis à billes 53 est fixé à l'extrémité inférieure élargie de la tige d'actionnement 37. Lorsqu'on alimente en courant le moteur 50, l'arbre de sortie du réducteur tourne, entraînant la vis à billes 53 laquelle déplace longitudinalement la tige d'actionnement 37. Le moteur peut être commandé depuis la surface pour tourner dans l'un ou l'autre sens de façon à ouvrir ou fermer les bras d'ancrage 25. La chambre 45 communique avec l'intérieur du boîtier par un passage 54, de façon que les espaces libres soient occupés par du fluide hydraulique qui baigne le moteur 50, la butée 52 et la vis à billes 53. Des passages sont prévus entre le boîtier 47 et le corps pour permettre le câblage des conducteurs électriques depuis les connecteurs 32 jusqu'au bas de la chambre 45.In the second chamber 45, is placed a housing 46 which contains motor members for longitudinally moving the actuating rod 37. To the lower part of the housing 47 is fixed an assembly 50 formed by an alternating current motor and a reduction gear. The gear unit output shaft is connected by an Oldham seal 51 to a ball bearing 52 and then to a ball screw 53. The nut element of the ball screw 53 is fixed to the enlarged lower end of the actuating rod 37. When the motor 50 is supplied with current, the output shaft of the reduction gear rotates, driving the ball screw 53 which moves the actuating rod 37 longitudinally. The motor can be controlled from the surface to rotate in either direction so as to open or close the anchoring arms 25. The chamber 45 communicates with the interior of the housing through a passage 54, so that the free spaces are occupied by hydraulic fluid which bathes the motor 50, the stop 52 and the ball screw 53. Passages are provided between the housing 47 and the body to allow the wiring of the electrical conductors from the connectors 32 to the bottom of the chamber 45.

A la partie inférieure de la chambre 45, le corps comprend un tube axial 54 dont l'intérieur communique avec la chambre 45. A sa périphérie, le corps comporte de plus une paroi cylindrique 55 autour du tube 54 de façon à délimiter une chambre annulaire 56 dans laquelle coulisse un piston flottant 57, égalisateur de pression. Au-dessus du piston flottant 57, la chambre annulaire 56, remplie de fluide hydraulique, communique avec l'intérieur du tube 54 par un passage 60. La face inférieure du piston 57 est en contact avec les fluides du sondage par un passage 61. L'étanchéité entre le piston et le tube 54 est réalisée par un joint 62 et celle entre le piston et la paroi cylindrique 55 par un joint 63.At the lower part of the chamber 45, the body comprises an axial tube 54 the interior of which communicates with the chamber 45. At its periphery, the body also has a cylindrical wall 55 around the tube 54 so as to delimit an annular chamber 56 in which a floating piston 57 slides, pressure equalizer. Above the floating piston 57, the annular chamber 56, filled with hydraulic fluid, communicates with the interior of the tube 54 by a passage 60. The underside of the piston 57 is in contact with the probing fluids by a passage 61. The seal between the piston and the tube 54 is produced by a seal 62 and that between the piston and the cylindrical wall 55 by a seal 63.

La partie supérieure 23 du corps se prolonge vers le bas, en dessous de la chambre annulaire 56, par un mandrin 65 qui pénètre dans la partie inférieure 24 du corps. Un joint 66 assure l'étanchéité entre cette partie inférieure 24 et une extrémité annulaire 67 de la partie supérieure 23. La partie inférieure 24 du corps peut s'écarter et tourner par rapport à l'extrémité annulaire 67 au niveau de l'épaulement 59. Dans la partie inférieure 24.du corps et autour du mandrin 65, est monté mobile un manchon 70 entre une position haute (figure 2B) et une position basse (figure 4). Le mandrin 65 est percé d'un canal axial 68 qui met en communication par l'intérieur du tube 54 la chambre 45 avec une autre chambre 69 réalisée dans la partie inférieure du corps. Le canal 68 sert aussi de passage pour les conducteurs électriques.The upper part 23 of the body extends downwards, below the annular chamber 56, by a mandrel 65 which penetrates into the lower part 24 of the body. A seal 66 seals between this lower part 24 and an annular end 67 of the upper part 23. The lower part 24 of the body can move away and rotate relative to the annular end 67 at the level of the shoulder 59 In the lower part 24. Of the body and around the mandrel 65, a sleeve 70 is movably mounted between a high position (FIG. 2B) and a low position (FIG. 4). The mandrel 65 is pierced with an axial channel 68 which places the chamber 45 in communication with the interior of the tube 54 with another chamber 69 produced in the lower part of the body. Channel 68 also serves as a passage for electrical conductors.

Une liaison déconnectable relie le manchon, en position basse, à la partie supérieure du corps. Au niveau de cette liaison, la figure 2B est une coupe selon la ligne 5-5 de la figure 3. Sur le mandrin 65 sont fixés, par des vis 71, des ergots 72 diamétralement opposés ayant deux côtés parallèles à la direction longitudinale et un bord supérieur en forme de V renversé. Dans le manchon 70 sont découpées des fenêtres 73 opposées ayant des rampes obliques à leur partie supérieure. Les ergots 72 sont placés dans les fenêtres 73 dont les dimensions sont choisies pour permettre, en position haute du manchon, des mouvements limités longitudinalement et angulairement, du mandrin 65 par rapport au manchon 70. Les bords supérieurs des ergots 78 et des fenêtres 73 forment des rampes qui immobilisent vers le bas le manchon 70 dans une première position correspondant angulairement au zéro des moyens de détection angulaires.A disconnectable link connects the sleeve, in the low position, to the upper part of the body. At this connection, FIG. 2B is a section along line 5-5 of FIG. 3. On the mandrel 65 are fixed, by screws 71, diametrically opposed lugs 72 having two sides parallel to the longitudinal direction and a upper edge in an inverted V shape. In the sleeve 70 are cut opposite windows 73 having oblique ramps at their upper part. The pins 72 are placed in the windows 73, the dimensions of which are chosen to allow, in the upper position of the sleeve, limited movements longitudinally and angularly, of the mandrel 65 relative to the sleeve 70. The upper edges of the pins 78 and windows 73 form ramps which immobilize the sleeve 70 downwards in a first position angularly corresponding to the zero of the angular detection means.

Le manchon a une partie supérieure de diamètre plus faible autour de laquelle est placé un ressort hélicoïdal 74 monté en compression entre ce manchon et un épaulement 75 de la partie inférieure du corps. Lorsque les fenêtres viennent en appui sur le haut des ergots (figure 4), le manchon 70 est immobilisé en position basse par rapport au mandrin 65 et le ressort 74 applique aux deux parties dù corps une force de rappel qui les sollicite l'une vers l'autre. Cette force de rappel est suffisante pour maintenir les deux parties du corps en position rétractée lorsque l'appareil est suspendu par le câble 12 lors de sa descente dans le sondage. Le mouvement vers le haut du manchon 70 est limité par l'épaulement 75 de la partie inférieure du corps contre lequel vient en butée l'extrémité supérieure du manchon.The sleeve has an upper part of smaller diameter around which is placed a helical spring 74 mounted in compression between this sleeve and a shoulder 75 of the lower part of the body. When the windows come to bear on the top of the lugs (FIG. 4), the sleeve 70 is immobilized in the low position relative to the mandrel 65 and the spring 74 applies to the two parts of the body a restoring force which biases them one towards the other. This restoring force is sufficient to maintain the two parts of the body in the retracted position when the device is suspended by the cable 12 when it descends into the borehole. The upward movement of the sleeve 70 is limited by the shoulder 75 of the lower part of the body against which the upper end of the sleeve abuts.

L'appareil comprend des moyens de détection des mouvements longitudinaux et angulaires entre le manchon et le mandrin. Ces moyens de détection, décrits en détail dans le brevet français antérieur déjà cité No. 24 81 737 du 30 avril 1980 et la EP-A-39 278, comprennent deux transformateurs différentiels. Un premier transformateur à bobines axiales comporte un primaire 80 fixé au mandrin et un secondaire formé de deux bobines 81 et 82 fixées au manchon. Ce premier transformateur détecte les mouvements longitudinaux entre les parties du corps tout en étant insensible aux mouvements angulaires. Un deuxième transformateur à bobines radiales comportant un primaire 83 fixé au mandrin et un secondaire formé de deux bobines 84 et 85 fixées au manchon, détecte les mouvements angulaires mais est insensible aux mouvements longitudinaux entre les parties du corps. Au zéro des moyens de détection longitudinaux, le primaire 80 du premier transformateur est centré entre les deux bobines 81 et 82 du secondaire comme représenté sur la figure 2B. Au zéro des moyens de détection angulaires le primaire 83 du deuxième transformateur a son axe perpendiculaire à celui des bobines 84 et 85 du secondaire. Le manchon et le mandrin sont placés avant la mesure dans cette position initiale par l'interaction des ergots 72 et des fenêtres 73.The apparatus includes means for detecting longitudinal and angular movements between the sleeve and the mandrel. These detection means, described in detail in the previously cited French patent No. 24 81 737 of April 30, 1980 and EP-A-39 278, include two differential transformers. A first transformer with axial coils comprises a primary 80 fixed to the mandrel and a secondary formed by two coils 81 and 82 fixed to the sleeve. This first transformer detects longitudinal movements between parts of the body while being insensitive to angular movements. A second transformer with radial coils comprising a primary 83 fixed to the mandrel and a secondary formed by two coils 84 and 85 fixed to the sleeve, detects angular movements but is insensitive to longitudinal movements between the parts of the body. At zero of the longitudinal detection means, the primary 80 of the first transformer is centered between the two coils 81 and 82 of the secondary as shown in FIG. 2B. At zero of the angular detection means the primary 83 of the second transformer has its axis perpendicular to that of the coils 84 and 85 of the secondary. The sleeve and the mandrel are placed before the measurement in this initial position by the interaction of the pins 72 and the windows 73.

Un boîtier 86 contenant des organes moteurs est monté coulissant dans la partie inférieure 24 du corps en dessous du manchon 70. L'intérieur du boîtier communique avec la chambre 69 par un passage 88. Dans le boîtier 86 est fixé un ensemble 87 constitué par un moteur électique à courant alternatif et un réducteur. L'arbre de sortie 90 du réducteur, monté tournant dans le boîtier par une butée à billes 91, est connecté à l'arbre fileté d'une vis à bille 92. L'organe écrou de la vis à bille 92 est fixé à une tige d'actionnement 93 qui sort du boîtier 86 et traverse une cloison transversale 94 du corps fermant vers le bas la chambre 69 remplie de fluide hydraulique. L'étanchéité entre la tige d'actionnement 93 et la cloison transversale 94 est assurée par un joint 95. En dessous de la cloison transversale 94, le corps comporte des découpes 96 dans lesquelles sont disposés trois bras d'ancrage 26 articulés sur des pivots 97. En dessous des découpes 96, la tige d'actionnement 93 traverse un alésage 100 réalisé dans l'axe du corps pour déboucher dans une chambre 101. Un joint 102 assure l'étanchéité entre la tige 93 et le corps. Entre les joints 95 et 102, la tige d'actionnement a une section transversale triangulaire avec trois rainures transversales 103. Sur chaque bras d'ancrage 26 est monté tournant un pion 104 ayant une nervure en saillie qui s'engage dans l'une des rainures 103.A housing 86 containing driving members is slidably mounted in the lower part 24 of the body below the sleeve 70. The interior of the housing communicates with the chamber 69 through a passage 88. In the housing 86 is fixed an assembly 87 constituted by a alternating current electric motor and a reducer. The output shaft 90 of the reducer, mounted rotatably in the housing by a ball bearing 91, is connected to the threaded shaft of a ball screw 92. The nut member of the ball screw 92 is fixed to a actuating rod 93 which leaves the housing 86 and passes through a transverse partition 94 of the body closing down the chamber 69 filled with hydraulic fluid. The seal between the actuating rod 93 and the transverse partition 94 is ensured by a seal 95. Below the transverse partition 94, the body has cutouts 96 in which are arranged three anchoring arms 26 articulated on pivots 97. Below the cutouts 96, the actuating rod 93 passes through a bore 100 made in the axis of the body to open into a chamber 101. A seal 102 seals between the rod 93 and the body. Between the seals 95 and 102, the actuating rod has a triangular cross section with three transverse grooves 103. On each anchoring arm 26 is mounted rotating a pin 104 having a projecting rib which engages in one of the grooves 103.

L'ensemble moteur-réducteur peut être alimenté en courant électrique de façon à déplacer la tige d'actionnement 93, soit vers le bas, soit vers le haut, par rapport au boîtier 86. Un canal longitudinal 105 découpé dans la tige d'actionnement 98 fait communiquer la chambre 69 avec la chambre 101. Un conducteur électrique placé dans le canal 105 est relié à un connecteur 106 monté de façon isolée et étanche au bas de la partie inférieure 24 du coprs. Sur cette extrémité est fixée par des vis 107 la partie supérieure 108 du support 22 d'explosifs. Un détonateur élecrique (non représenté) pour la mise à feu de cet explosif est relié au connecteur 106.The motor-reduction unit can be supplied with electric current so as to move the actuating rod 93, either downwards or upwards, relative to the housing 86. A longitudinal channel 105 cut out in the actuating rod 98 communicates the chamber 69 with the chamber 101. An electrical conductor placed in the channel 105 is connected to a connector 106 mounted in an isolated and sealed manner at the bottom of the lower part 24 of the body. On this end is fixed by screws 107 the upper part 108 of the support 22 of explosives. An electric detonator (not shown) for igniting this explosive is connected to connector 106.

Pour effectuer une mesure de point de coincement, on connecte tout d'abord l'appareil de fond 10 au câble 12 afin de le descendre dans les tiges 11. Les bras d'ancrage supérieurs 25 et inférieurs 26 sont refermés et les différents organes contenus dans la partie inférieure du corps sont dans la position représentée sur la figure 4. En particulier, le boîtier 86 est en butée basse contre la cloison transversale 94. La tige d'actionnement 93, en position haute dans le boîtier 86, maintient fermés les bras d'ancrage inférieurs 26. Le manchon 70, repoussé par le ressort 74, est en position basse, immobilisé par les ergots 72 sur lesquels vient en appui le haut des fenêtres 73. Le détecteur de mouvements angulaires formé par les bobines 83, 84 et 85 est ainsi placé dans sa position angulaire de zéro. Le ressort 74 applique aussi à la partie inférieure du corps une force de rappel ascendante qui maintient les deux parties 23 et 24 en position rétractée.To perform a jamming point measurement, first connect the bottom device 10 to the cable 12 in order to lower it into the rods 11. The upper 25 and lower 26 anchoring arms are closed and the various members contained. in the lower part of the body are in the position shown in FIG. 4. In particular, the housing 86 is in bottom abutment against the transverse partition 94. The actuating rod 93, in the high position in the housing 86, keeps the lower anchoring arm 26. The sleeve 70, pushed back by the spring 74, is in the low position, immobilized by the pins 72 which bear on the top of the windows 73. The angular motion detector formed by the coils 83, 84 and 85 is thus placed in its angular position of zero. The spring 74 also applies to the lower part of the body an ascending restoring force which maintains the two parts 23 and 24 in the retracted position.

On descend ensuite l'appareil 10 dans le sondage jusqu'à une première profondeur où l'on désire déterminer si les tiges sont libres. A cette profondeur, on alimente en courant le moteur 50 (figure 2A), de façon à écarter les bras d'ancrage supérieurs 25. Après ancrage de la partie supérieure du corps 23 et après avoir relâché la tension du câble 12, on alimente en courant le moteur 87. Les bras d'ancrage inférieurs s'écartent du corps jusqu'à venir en appui contre la paroi interne des tiges 11. Le boîtier 86 remonte légèrement dans la partie inférieure du corps jusqu'à venir en appui sur le bas du manchon 70. A cet instant, la force latérale d'application des bras d'ancrage 26 est déterminée par la force longitudinale de rappel du ressort 24, transmise par le manchon 70 et le boîtier 86 à la tige d'actionnement 93. Les bras d'ancrage 26 ayant atteint leur écartement maximal dans les tiges, arrêtent le déplacement de la tige d'actionnement 93 par rapport à la partie inférieure 24 du corps.The apparatus 10 is then lowered into the borehole to a first depth where it is desired to determine whether the rods are free. At this depth, the motor 50 is supplied with current (FIG. 2A), so as to separate the upper anchoring arms 25. After anchoring of the upper part of the body 23 and after having released the tension of the cable 12, running the motor 87. The lower anchoring arms move away from the body until they bear against the internal wall of the rods 11. The housing 86 rises slightly in the lower part of the body until it comes to bear on the bottom of the sleeve 70. At this instant, the lateral force of application of the anchoring arms 26 is determined by the longitudinal return force of the spring 24, transmitted by the sleeve 70 and the housing 86 to the actuating rod 93. The anchoring arm 26 having reached their maximum spacing in the rods, stop the movement of the actuating rod 93 relative to the lower part 24 of the body.

Lorsque le moteur continue à tourner, le boîtier 86 se déplace vers le haut entraînant le manchon 70 qui comprime le ressort 74. Ce mouvement se poursuit jusqu'à ce l'extrémité supérieure du manchon 70 vienne en appui contre l'épaulement 75. Le manchon 70 est alors bloqué en position haute dans la partie inférieure 24 du corps. Au cours de ce mouvement les surfaces de contact obliques des fenêtres et des ergots s'éloignent les unes des autres ce qui découple la liaison entre le manchon 70 et le mandrin 65. Par rapport au mandrin 65, le manchon 70, bloqué à cet instant dans la partie inférieure 24 du corps, est libre de se déplacer avec des mouvements limités angulairement vers la droite ou la gauche et longitudinalement en extension. Cette position haute du manchon, pour laquelle les moyens de détection angulaires et longitudinaux sont sensiblement au zéro, est représentée sur la figure 2B. L'appareil est alors prêt à effectuer une mesure, c'est-à-dire à détecter des mouvements entre les parties du corps lorsqu'on applique aux tiges en surface des contraintes de traction ou de torsion.When the engine continues to run, the housing 86 moves upward, causing the sleeve 70 which compresses the spring 74. This movement continues until the upper end of the sleeve 70 comes to bear against the shoulder 75. The sleeve 70 is then locked in the high position in the lower part 24 of the body. During this movement, the oblique contact surfaces of the windows and the pins move away from each other, which decouples the connection between the sleeve 70 and the mandrel 65. With respect to the mandrel 65, the sleeve 70, blocked at this instant in the lower part 24 of the body, is free to move with limited movements angularly to the right or to the left and longitudinally in extension. This upper position of the sleeve, for which the angular and longitudinal detection means are substantially at zero, is shown in FIG. 2B. The device is then ready to carry out a measurement, that is to say to detect movements between the parts of the body when tensile or torsional stresses are applied to the rods at the surface.

Après une telle mesure, on alimente en courant les moteurs 87 et 50 pour refermer les bras d'ancrage inférieurs et supérieurs. On peut alors déplacer l'appareil de fond au moyen du câble 12 pour effectuer d'autres mesures à différentes profondeurs.After such a measurement, the motors 87 and 50 are supplied with current to close the upper and lower anchoring arms. The bottom device can then be moved using the cable 12 to carry out other measurements at different depths.

Pendant les déplacements de l'appareil dans le sondage (figure 4) le manchon 70 est maintenu sur le mandrin 65 dans une position basse pour laquelle le détecteur de mouvements angulaires est sensiblement au zéro. Par contre, dans cette position du manchon, le détecteur de mouvements longitudinaux indique une élongation maximale. En effet, la bobine 80 est décalée vers le haut d'une distance d par rapport au point milieu des bobines 81 et 82.During the movements of the apparatus in the borehole (FIG. 4) the sleeve 70 is held on the mandrel 65 in a low position for which the angular movement detector is substantially at zero. On the other hand, in this position of the sleeve, the longitudinal movement detector indicates a maximum elongation. In fact, the coil 80 is offset upwards by a distance d from the midpoint of the coils 81 and 82.

Après ancrage des deux parties du corps, le manchon 70 est amené, par rapport au mandrin, dans sa position haute qui, angulairement, n'est pas modifiée depuis la position basse précédente. Pour cette position, le détecteur de mouvements longitudinaux est sensiblement au zéro. A partir de cette position, le manchon 70 solidaire de la partie inférieure du corps est découplé de la partie supérieure. Toute force de rappel tendant à s'opposer à des déplacements longitudinaux ou angulaires entre les parties du corps est supprimée pendant la mesure. En outre, on peut suivre en surface l'indication fournie par le détecteur de mouvements longitudinaux lors de l'ancrage de l'appareil pour s'assurer de son bon fonctionnement. Lorsque ce détecteur indique que les deux parties du corps de sont rapprochées l'une de l'autre depuis une valeur d à une valeur sensiblement nulle, l'opérateur sait que le manchon 70 s'est correctement déplacé dans la partie inférieure du corps de sa position basse à sa position haute. On dispose ainsi d'une information sur le bon fonctionnement du système automatique de remise à zéro de l'appareil.After anchoring of the two parts of the body, the sleeve 70 is brought, relative to the mandrel, in its high position which, angularly, is not modified from the previous low position. For this position, the longitudinal movement detector is substantially at zero. From this position, the sleeve 70 secured to the lower part of the body is decoupled from the upper part. Any restoring force tending to oppose longitudinal or angular movements between the parts of the body is eliminated during the measurement. In addition, the indication provided by the longitudinal movement detector when the device is anchored can be followed on the surface to ensure that it functions properly. When this detector indicates that the two parts of the body are close to each other from a value d to a value substantially zero, the operator knows that the sleeve 70 has moved correctly in the lower part of the body its low position to its high position. This provides information on the proper functioning of the automatic reset system of the device.

Le dispositif qui vient d'être décrit peut évidemment faire l'objet de nombreuses variantes tout en restant dans le cadre de l'invention. En particulier, les moyens de détection peuvent être réalisés sous une forme différente du capteur électromagnétique décrit ci-dessus.The device which has just been described can obviously be the subject of numerous variants while remaining within the scope of the invention. In particular, the detection means can be produced in a form different from the electromagnetic sensor described above.

Claims (18)

1. A method for detecting the stuck point of a conduit (11) in a borehole (13) comprising the steps of:
- lowering in the conduit (11) an apparatus comprising a body (21) having first and second parts (23, 24) movably mounted with respect to each other and normally biased toward each other by a biasing force (74);
- anchoring each of said parts inside the conduit (11) in response to a control from the surface;
- detecting, by detecting means (80 to 85), the relative movements between said parts when the conduit (11) is deformed by applying stresses from the surface; characterized in that it includes furthermore the step consisting in:
- uncoupling said biasing force (74) from said first part (23) after said anchoring step and before said detecting step to eliminate the aplication of said force (74) between said parts during said detecting step.
2. The method of claim 1, characterized in that it further comprises the steps of:
- applying the biasing force (74) between said second part (24) and a movable member (70) coupled to said first part (23) before the anchoring step, but adapted to be uncoupled from said first part (23); and
- after said anchoring step, uncoupling said movable member (70) form said first part (23) to uncouple the biasing force (74) from said first part (23).
3. The method of claim 2 wherein said detecting means comprise means for detecting angular movements (83, 84, 85) between said parts (23, 24), characterized in that it further comprises the steps of:
- before said anchoring step, maintaining said angular detecting means (83, 84, 85) in a zero position uncoupled from a second of said parts (23, 24) of the body; and
- coupling said angular detecting means (83, 84, 85) to said second part (24) after said anchoring step and before said detecting step, with out substantially changing the zero position of said angular detecting means (83, 84, 85).
4. The method of claim 3, characterized in that it further comprises the steps of:
- detecting by said detecting means (81, 82, 83) the relative movements between said first part (23) of the body and said movable member (70) which is uncoupled from the second part (24) of the body before the anchoring step; - maintaining said member (70) in the zero position with respect tc said first part (23), before the anchoring step; and
- after said anchoring step, blocking said member (70) to said second part (24) of the body while uncoupling said member (70) from said first part (23), to detect the movements between said parts (23, 24) of the body by said detecting means (81 to 85).
5. Apparatus for detecting the stuck point of a conduit (11) in a borehole (13) comprising:
- a body (10) adapted to be suspended from a cable (12) and having two parts (23, 24) movably mounted with respect to each other each part being adapted to be anchored inside the conduit (11) by a control from the surface; - means for detecting (80 to 85) relative movements between said parts (23, 24) when the conduit (11) is deformed by applying stresses from the surface; and
- biasing means (74) in the body member normally applying to said parts (23, 24) of the body member a longitudinal biasing force which loads them toward each other; characterized in that it further comprises:
- disconnectable linking means (65, 70) for linking the biasing means (74) longitudinally to a first of said parts (23, 24) of the body member; and
- driving means (87, 92, 86) in the body member for uncoupling the linking means (65, 70) from the first part (23) of the body, when said parts (23, 24) are anchored inside the conduit (11), in order to eliminate the application of the biasing force between said parts (23, 24) when detecting relative movements.
6. Apparatus according to claim 5, characterized in that said linking means (65, 70) comprise:
- a member movably (70) mounted between a first position coupled to said first part (23) of the body and a second position uncoupled from said first part (23), said biasing means (74) being placed between the second part (24) of the body and said member (70) to load said member (70) toward the first position and apply the biasing force between said first and second parts (23, 24) when said member (70) is in the first position.
7. The apparatus of claim 6 characterized in that said driving means (87, 92, 86) are placed in the second part (24) of the body and adapted for moving said member (70) toward said second position to uncouple said member (70) from said first part (23).
8. The apparatus of claim 7, characterized in that:
- said member (70) is blocked in relation to said second part (24) in the second position and uncoupled from said second part (24) in the first position; and
- said detecting means (80 to 85) are placed on said member (70) and said first part (23) of the body to be sensitive to movements between said member (70) and said first part (23).
9. The apparatus of claim 8, characterized in that said detecting means (80 to 85) comprise means for detecting angular movements (83 to 85) between said member (70) and said first part (24), and in that it further comprises:
- resetting means (72, 73) for angularly placing said member (70) in relation to the first part (23) in a zero position of said angular detecting means (83 to 85) when said member (70) is in the first position.
10. The apparatus of claim 9, characterized in that said resetting means comprise contact surfaces (73,78) between said member (70) and the first part (23) of the body, at least one of said contact surfaces (73, 78) having oblique ramps for placing said member (70) under the action of said biasing means (74), in said zero position in relation to the first part (23) of the body.
11. The apparatus of claim 10, characterized in that it comprises a shoulder (75) placed in the second part (24) of the body so that said driving means (87, 92, 86) immobilize said member (70) in said second position against said shoulder (75).
12. The apparatus of any one of claims 9 to 10, characterized in that said angular movement detecting means (83, 84, 85) comprise a radial-coil transformer having primary (83) and secondary (84, 85) windings fixed respectively to the first part (23) of the body and to said member (70).
13. The apparatus of any one of claims 9 to 10, characterized in that said detecting means (80 to 85) comprise means for detecting longitudinal movements (80, 81, 82) between said first part (23) and said member (70) to indicate the movements of said member (70) produced by said driving means (87,92,86).
14. The apparatus of claim 13, characterized in that said longitudinal movement detecting means (80, 81, 82) comprise an axial-coil transformer having primary (80) and secondary (81, 82) windings fixed respectively to the first part (23) of the body and to said member (70).
15. The apparatus of any one claims 7 to 14, characterized in that said driving means(87, 92, 93) are adapted to anchor the lower part (24) of the body in the conduit (11) before moving said member (70) toward the second position.
16. The apparatus of claim 15, characterized in that said driving means (87, 92) comprise first and second actuating elements (86, 93) movably mounted in the second part (24) of the body member to extend longitudinally from each other, one of said actuating elements (93) being connected to actuate anchoring arms articulated on said second part (24) to move them away from the body and anchor them inside the conduit (11), and said other actuating element (86) being adapted to move said member (70) from the first position to the second position.
17. The apparatus of any one of claims 7 to 16, characterized in that said first and the second. parts (23, 24) of the body, are respectively the upper and the lower parts of the body, said driving means (87, 92) being adapted to move said member (70) after the anchoring of the lower part (24) of the body.
EP81402090A 1980-12-31 1981-12-30 Method and apparatus for determining the stuck point of drill pipes in a borehole Expired EP0055675B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8027868A FR2497266A1 (en) 1980-12-31 1980-12-31 DEVICE FOR DETECTING THE POINT OF ROD ENCLOSURE IN A SURVEY
FR8027868 1980-12-31

Publications (2)

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EP0055675A1 EP0055675A1 (en) 1982-07-07
EP0055675B1 true EP0055675B1 (en) 1985-03-20

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EP81402090A Expired EP0055675B1 (en) 1980-12-31 1981-12-30 Method and apparatus for determining the stuck point of drill pipes in a borehole

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US (1) US4402219A (en)
EP (1) EP0055675B1 (en)
JP (1) JPS57135310A (en)
AU (1) AU547081B2 (en)
BR (1) BR8107932A (en)
CA (1) CA1163190A (en)
DE (1) DE3169492D1 (en)
EG (1) EG14815A (en)
FR (1) FR2497266A1 (en)
IE (1) IE52218B1 (en)
IN (1) IN157830B (en)
MX (1) MX158744A (en)
NO (1) NO155635C (en)
OA (1) OA06977A (en)
PH (1) PH19566A (en)

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US4708204A (en) * 1984-05-04 1987-11-24 Nl Industries, Inc. System for determining the free point of pipe stuck in a borehole
DE3605036A1 (en) * 1985-04-10 1986-10-16 Gerd 3167 Burgdorf Hörmansdörfer METHOD AND DEVICE FOR DETERMINING THE CLAMPING POINT OF A STRING IN A DRILL HOLE
US5375476A (en) * 1993-09-30 1994-12-27 Wetherford U.S., Inc. Stuck pipe locator system
US6851476B2 (en) * 2001-08-03 2005-02-08 Weather/Lamb, Inc. Dual sensor freepoint tool
US7389183B2 (en) * 2001-08-03 2008-06-17 Weatherford/Lamb, Inc. Method for determining a stuck point for pipe, and free point logging tool
US7383876B2 (en) * 2001-08-03 2008-06-10 Weatherford/Lamb, Inc. Cutting tool for use in a wellbore tubular
US7195069B2 (en) * 2003-06-26 2007-03-27 Weatherford/Lamb, Inc. Method and apparatus for backing off a tubular member from a wellbore
US7004021B2 (en) * 2004-03-03 2006-02-28 Halliburton Energy Services, Inc. Method and system for detecting conditions inside a wellbore
US7252143B2 (en) * 2004-05-25 2007-08-07 Computalog Usa Inc. Method and apparatus for anchoring tool in borehole conduit
JP5153534B2 (en) * 2008-09-16 2013-02-27 株式会社ハーモニック・ドライブ・システムズ Drill bit shaft structure of drilling rig
US20110198099A1 (en) * 2010-02-16 2011-08-18 Zierolf Joseph A Anchor apparatus and method
CN104280002B (en) * 2014-10-31 2017-02-08 江苏楷正建设有限公司 Linearity detecting table for drill rod
CN106351646B (en) * 2016-09-23 2020-03-24 北京信息科技大学 Underground card measuring system with fiber grating sensing device
NO343697B1 (en) * 2017-05-23 2019-05-13 Altus Intervention Tech As Method and apparatus for performing a survey of tubing which is stuck in a borehole, e.g. for determining a free point

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Also Published As

Publication number Publication date
FR2497266A1 (en) 1982-07-02
MX158744A (en) 1989-03-10
IE812828L (en) 1982-06-30
FR2497266B1 (en) 1983-12-16
JPS6365798B2 (en) 1988-12-16
EP0055675A1 (en) 1982-07-07
JPS57135310A (en) 1982-08-20
AU7837981A (en) 1982-07-08
US4402219A (en) 1983-09-06
NO155635C (en) 1987-05-06
BR8107932A (en) 1982-09-14
PH19566A (en) 1986-05-21
AU547081B2 (en) 1985-10-03
OA06977A (en) 1983-07-31
IN157830B (en) 1986-07-05
IE52218B1 (en) 1987-08-05
EG14815A (en) 1985-03-31
DE3169492D1 (en) 1985-04-25
NO814303L (en) 1982-07-01
CA1163190A (en) 1984-03-06
NO155635B (en) 1987-01-19

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