WO1985000634A1 - Power tong for the connection of drilling pipes - Google Patents

Power tong for the connection of drilling pipes Download PDF

Info

Publication number
WO1985000634A1
WO1985000634A1 PCT/FR1984/000177 FR8400177W WO8500634A1 WO 1985000634 A1 WO1985000634 A1 WO 1985000634A1 FR 8400177 W FR8400177 W FR 8400177W WO 8500634 A1 WO8500634 A1 WO 8500634A1
Authority
WO
WIPO (PCT)
Prior art keywords
clamp
rod
axis
rotation
rods
Prior art date
Application number
PCT/FR1984/000177
Other languages
French (fr)
Inventor
Roland Le Roc'h
Marc Lemaire
Original Assignee
Brissonneau Et Lotz Marine
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Brissonneau Et Lotz Marine filed Critical Brissonneau Et Lotz Marine
Priority to BR8406968A priority Critical patent/BR8406968A/en
Priority to GB08507898A priority patent/GB2156256B/en
Publication of WO1985000634A1 publication Critical patent/WO1985000634A1/en

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Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B19/00—Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables
    • E21B19/16—Connecting or disconnecting pipe couplings or joints
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D311/00—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only hetero atom, condensed with other rings

Definitions

  • the invention relates to a machine for applying a significant screwing or screwing torque to rods screwed end to end, in particular vertical drilling rods.
  • a machine which comprises a lower clamp, fixed in rotation relative to the vertical axis of the drill string, for gripping the upper part of a rod itself constituting the 'upper end of the drill string, and an upper clamp for gripping the lower end of a rod that is to be connected to the upper end of the drill string or disassemble from this upper end.
  • the upper clamp is movable in rotation about the vertical axis of the drill string relative to the lower clamp, in order to apply significant torque to the upper rod on which it is tightened in order to block this rod at the end of screwing or to unlock it at the start of unscrewing.
  • the upper clamp is also movable vertically relative to the lower clamp to allow, when it is moved away from this lower clamp, the application of screwing or quick unscrewing means on the lower end of the rod to be screwed or unscrewed.
  • the upper clamp comprises one or two fixed jaws, intended to be applied to the external surface of the rod or, more precisely, to the external surface of a connection piece by screwing provided at the end of the rod, and two clamping jaws which are pushed onto the external surface of this connection endpiece by hydraulic jacks oriented radially towards the axis of the rod and carried by the rigid frame of the clamp.
  • the angle formed by the radial directions of the two cylinders is of the order of 120 °, and the radial thrust forces developed by these cylinders are very large and can for example be greater than 15,000 decalîewton.
  • the invention aims in particular to avoid this drawback of the prior art. '
  • a machine for applying a torque 5 for screwing or unscrewing to rods screwed end to end comprising two pliers respectively lower and upper each comprising a rigid frame comprising jaws clamping actuated by jacks to grip respectively 0 the upper part of a lower rod and the lower part of an upper rod, the lower clamp being fixed in rotation about the axis of the rods and means being provided for rotate the upper clamp relative to the lower clamp by a determined angle around a vertical axis with a high torque in order to block the two rods at the end of screwing or unlock them at the start of unscrewing, characterized in that the clamping jaws of at least the upper clamp, which comprise at one end jaws intended to be applied under pressure to the rod , are ⁇ levers mounted for rotation about a vertical axis on the chassis
  • any tendency for the upper clamp to slide tightly on the lower end of the rod which could occur due to a decentring of the upper clamp, automatically reinforces the blocking and the tightening of the upper clamp.
  • '' a jaw on the rod, which prevents any slipping.
  • the horizontal tangent to the peripheral surface of the rod in the area of application of the jaw of a jaw on the rod extends between the ti ⁇ e and the axis of rotation of this jaw on the clamp frame and passes in the immediate vicinity of this axis of rotation.
  • the interaction between the actuating jacks of the clamping jaws, during the rotation of the clamp is made negligible.
  • the machine according to the invention can thus function correctly even if the actuating cylinders of the clamping jaws are not completely purged.
  • Figures 1 and 2 schematically show, in plan view and in elevation view, a machine according to the prior art
  • Figure 3 is a schematic plan view with partial cutaway, of a part of a machine according to the invention.
  • FIG. 4 is a partial sectional view along the line IV-IV of FIG. 3.
  • FIGS. 1 and 2. sché ⁇ matically representing the prior art.
  • the reference 10 designates the lower part of an upper rod drilling, provided with a male connection end piece 12 with external thread
  • the reference 14 designates the upper part of a lower rod, provided with a female end piece 16 connection with internal thread.
  • a lower clamp 18. fixed in rotation relative to the vertical axis of the rods 10 and 14, is clamped on the female end-piece 16 of the rod 14.
  • a clamp 20 movable in rotation around the axis of the rods, is clamped on the end piece 12 of the rod 10.
  • Hydraulic jacks allow the upper clamp 20 to rotate around the axis 13 of the rods by a determined angle with a significant torque, to block the rods one on the other at the end of the screwing and unlock them at the start of the unscrewing.
  • the upper clamp 20 comprises a rigid chassis 22 substantially in a U shape, surrounding on three sides the end piece 12 of the rod 10.
  • This chassis 22 carries one or two fixed jaws 24 and two mobi ⁇ jaws the 26 mounted at the ends of the piston rods of two hydraulic cylinders 28 oriented radially towards the axis 13 of the rods.
  • the upper clamp 20 is mounted floating in a horizontal plane so as to be able to center automatically on the axis 13 of the rods when the jacks 28 are supplied with hydraulic fluid under pressure.
  • the radial thrust forces developed by the two jacks 28 are not always, in practice, strictly equal to each other and, when the upper clamp 20 is rotated around the axis 13 of the rods, the force developed by one of the jacks 28 acts on the other jack, hence a risk of decentering of the clamp 20 relative to the drilling rods and of sliding of the jaws of this clamp on the end piece 12 of the upper rod 10.
  • the machine according to the invention comprises, as in the prior art, a lower clamp fixed in rotation and an upper clamp intended to be driven in rotation about the axis of the rods for locking at the end of screwing and unlocking in start of unscrewing.
  • the lower clamp 30 is fixedly mounted on a frame or a lower support, not shown, - and comprises, on one side, a yoke 32 for supporting the vertical axis 34 of rotation of the cylinder 36 of a hydraulic cylinder 38 horizontal and. on the other hand, a yoke 40 for supporting the vertical axis of rotation 42 of the end of the piston rod 44 of a horizontal hydraulic cylinder 46 identical to the cylinder 38.
  • the end 48 of the piston rod of the first cylinder 38 is movable in rotation about a vertical axis 50 carried by a yoke 52 of the rigid frame 54 of the upper clamp 56, while the cylinder 58 of the second cylinder 46 is mobile about a vertical axis of rotation 60 carried by a yoke 62 of the chassis 54 of the upper clamp 56.
  • the vertical axes of rotation 34, 42, 50, 60 of the jacks 38 and 46 and of the ends of their piston rods are at the same distance from the axis 13 of the rods when the two clamps are tightened on the connection ends of these rods, so that, when the jacks 3 and 46 are supplied with pressure, they rotate the upper clamp 56 around the vertical axis 13 of the rods, in one direction or the other.
  • the rigid frame 54 of the upper clamp 56 forms a box inside which are housed two identical hydrau- lic cylinders 64 and two identical clamping jaws 66 which are symmetrically arranged relative to a median vertical plane 67 passing through the axis r stems 13.
  • Each clamping jaw 66 is mounted for rotation about a vertical axis 68 carried by the chassis 54 and comprises at one end, a jaw 70 suitable for being applied to the connection end piece 12 of the upper rod 20.
  • each jaw 66 forms a yoke carrying the vertical axis of rotation 72 of the end of the piston rod of the associated jack 64 which, at the opposite end of its cylinder, is mounted for rotation about a vertical axis 74 carried by the frame 54 of the upper clamp.
  • the axes of rotation 74 of the jacks 64 on the chassis 54 are adjacent to each other and the longitudinal axes of these two jacks form an angle of approximately 45 ° between them.
  • Each jaw 66 is mounted so as to be self-locking on the connection end piece of a rod for a determined direction of rotation of the upper clamp relative to the axis of the rod, that is to say that when the jaw 70 of a jaw is applied to the end piece of the rod, the horizontal tangent to the cylindrical surface of the end piece in the area of application of the jaw 70 extends between this end piece and the axis of rotation 68 of the clamping jaw.
  • the two clamping jaws 66 are symmetrical with respect to the median vertical plane 67 of the clamp, one of the jaws is self-locking on the end of the rod for a determined direction of rotation of the clamp around the axis 13 beyond rod and the other jaw is self-locking in the opposite direction of rotation about this axis.
  • the axis of rotation 68 of one of the clamping jaws 66 ends at its lower part by a cylindrical finger, which is received and guided in a curved groove 80 formed in the upper horizontal face of the chassis of the lower clamp. 30 and which is centered on the axis 13 of the rods.
  • the machine according to the invention comprising the lower 30 and upper 56 clamps, is used as in the prior art.
  • any tendency to slip is eliminated and the actuators 64 for actuating the clamping jaws no longer have an action on each other even if the actuators are not perfectly purged, and if one of the end pieces is slightly ovalized, so that the machine according to the invention is much more reliable than the corresponding machines of the prior art.
  • the machine according to the invention operates satisfactorily with rods having different outside diameters, for example between 7 and 22 cm.

Landscapes

  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Mechanical Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Earth Drilling (AREA)
  • Clamps And Clips (AREA)
  • Lubricants (AREA)
  • Mutual Connection Of Rods And Tubes (AREA)

Abstract

Machine enabling to apply a high rotation torque to pipes connected end to end in order to lock them at the end of the screwing or to unlock them at the beginning of the unscrewing. Each tong of the machine comprises two fixed jaws (76) applied to the extremity of a pipe and two clamping jaws (76) which are rotatingly mounted about a vertical axis of the tong and actuated by a hydraulic jack (64) one clamping jaw being self-locking for one rotation direction of the tong about the axis of the pipe, and the other clamping jaw being self-locking in the opposite rotation direction. The invention may be particularly applied to the assembly and disassembly of drill pipe strings.

Description

PINCE DE PUISSANCE POUR LE VISSAGE DES TIGES DE FORAGE POWER CLAMP FOR SCREWING DRILL RODS
L'invention concerne une machine pour appliquer un couple important de vissage ou de vissage à des tiges vissées bout à bout, en particulier des tiges verticales de forage.The invention relates to a machine for applying a significant screwing or screwing torque to rods screwed end to end, in particular vertical drilling rods.
Les opérations de vissage bout à bout des tiges et de dévis¬ sage doivent être répétées un très grand nombre de fois lorsqu'il faut constituer un train de tiges ayant une longueu de plusieurs milliers de mètres lors de la descente de ce train dans un puits de forage, ou bien pour démonter ce train de tiges lorsqu'on le remonte pour changer le trépan équipant l'extrémité inférieure du train ou pour effectuer des mesures ou des opérations de coffrage dans le puits.The operations of end-to-end screwing of the rods and unscrewing must be repeated a very large number of times when it is necessary to constitute a train of rods having a length of several thousand meters when the train is lowered into a well drilling, or to disassemble this drill string when it is reassembled to change the drill bit equipping the lower end of the train or to carry out measurements or formwork operations in the well.
On a déjà proposé d'automatiser ces opérations au moyen d'une machine qui comprend une pince inférieure, fixe en rotation par rapport à l'axe vertical du train de tiges, pour saisir la partie supérieure d'une tige constituant elle-même l'extré mité supérieure du train de tiges , et une pince supérieure destinée à saisir l'extrémité inférieure d'une tige que l'on veut raccorder à l'extrémité supérieure du train de tiges ou démonter de cette extrémité supérieure. La pince supé¬ rieure est mobile en rotation autour de l'axe vertical du train de tiges par rapport à la pince inférieure, pour appli¬ quer un couple important à la tige supérieure sur laquelle elle est serrée, afin de bloquer cette tige en fin de vissage ou la débloquer en début de dévissage. La pince supérieure est également déplaçable verticalement par rapport à la pince inférieure pour permettre, quand elle est écartée de cette pince inférieure, l'application de moyens de vissage ou de dévissage rapide sur l'extrémité inférieure de la tige à visser ou dévisser. rIt has already been proposed to automate these operations by means of a machine which comprises a lower clamp, fixed in rotation relative to the vertical axis of the drill string, for gripping the upper part of a rod itself constituting the 'upper end of the drill string, and an upper clamp for gripping the lower end of a rod that is to be connected to the upper end of the drill string or disassemble from this upper end. The upper clamp is movable in rotation about the vertical axis of the drill string relative to the lower clamp, in order to apply significant torque to the upper rod on which it is tightened in order to block this rod at the end of screwing or to unlock it at the start of unscrewing. The upper clamp is also movable vertically relative to the lower clamp to allow, when it is moved away from this lower clamp, the application of screwing or quick unscrewing means on the lower end of the rod to be screwed or unscrewed. r
Dans la technique actuelle, la pince supérieure comprend un ou deux mors fixes, destinés à être appliqués sur la surface extérieure de la tige ou, plus exactement, sur la surface extérieure d'un embout .de connexion par vissage prévu à l'extrémité de la tige, et deux mors de serrage qui sont poussés sur la surface extérieure de cet embout de connexion par des vérins hydrauliques orientés radialement vers l'axe de la tige et portés par le châssis rigide de la pince. L'angle formé par les directions radiales des deux vérins est de l'ordre de 120°, et les forces de poussée radiale dévelop¬ pées par ces vérins sont très importantes et peuvent être par exemple supérieures à 15 000 decalîewton. Ces forces de serrage très importantes de la tige dans la pince permettent d'appliquer un couple très important à cette tige pour son blocage sur le train de tiges en fin de vissage ou son dé¬ blocage en début de dévissage.In the current technique, the upper clamp comprises one or two fixed jaws, intended to be applied to the external surface of the rod or, more precisely, to the external surface of a connection piece by screwing provided at the end of the rod, and two clamping jaws which are pushed onto the external surface of this connection endpiece by hydraulic jacks oriented radially towards the axis of the rod and carried by the rigid frame of the clamp. The angle formed by the radial directions of the two cylinders is of the order of 120 °, and the radial thrust forces developed by these cylinders are very large and can for example be greater than 15,000 decalîewton. These very large clamping forces of the rod in the clamp make it possible to apply a very large torque to this rod for its blocking on the drill string at the end of screwing or its de¬ blocking at the start of unscrewing.
Toutefois, il arrive très souvent en pratique que les for¬ ces de poussée radiale développées par les vérins ne soient pas exactement égales l'une à l'autre, d'où il résulte un risque de décentre ent de la pince supérieure par rapport à l'axe du train de tiges, et un risque de glissement de cette pince lorsqu'elle est entraînée en rotation pour l'ap¬ plication du couple de vissage ou de dévissage. Ce risque de décentrement, qui peut être accentué par une faible ova- lisation de l'embout de connexion monté à lrextrémité de la tige, vient essentiellement de ce quril est très difficile de purger parfaitement ces vérins hydrauliques dont les cy¬ lindres contiennent souvent un volume d'air résiduel. Lorsque les vérins sont alimentés en pression, ces volumes d'air son comprimés à une pression qui est er. équilibre avec la pres¬ sion d'huile d'alimentation άes vérins. Lorsque la pince est ensuite entraînée en rotation, une partie de la force de 5 poussée radiale développée par l'un des vérins est transmise, par l'intermédiaire de la tige, à l'autre vérin dont le volu¬ me d'air résiduel est alors comprimé davantage et dont le mors a tendance à glisser sur la surface de l'embout de connexion monté à l'extrémité de la tige. 0However, it very often happens in practice that the radial thrust for¬ developed by the cylinders are not exactly equal to each other, which results in a risk of decentering ent of the upper clamp relative to the axis of the drill string, and a risk of sliding of this clamp when it is rotated for the application of the screwing or unscrewing torque. This risk of shift, which may be accentuated by a low ova- lisation of the connection fitting mounted at the end r of the rod, essentially just that r it is very difficult to perfectly purge these hydraulic cylinders whose cy¬ Linders often contain a residual volume of air. When the cylinders are supplied with pressure, these volumes of air are compressed to a pressure which is er. balance with the supply oil pressure on the cylinders. When the clamp is then driven in rotation, part of the radial thrust force developed by one of the cylinders is transmitted, via the rod, to the other cylinder whose volume of residual air is then further compressed and the jaw tends to slide on the surface of the connection end piece mounted at the end of the rod. 0
L'invention vise notamment à éviter cet inconvénient de la technique antérieure.'The invention aims in particular to avoid this drawback of the prior art. '
Elle propose à cet effet une machine pour appliquer un couple 5 de vissage ou de dévissage à des tiges vissées bout à bout, en particulier des tiges verticales de forage, comprenant deux pinces respectivement inférieure et supérieure compre¬ nant chacune un châssis rigide comportant des mâchoires de serrage actionnées par des vérins pour saisir respectivement 0 la partie supérieure d'une tige inférieure et la partie infé¬ rieure d'une tige supérieure, la pince inférieure étant fixe en rotation autour de l'axe des tiges et des moyens étant prévus pour faire tourner la pince supérieure par rapport à la pince inférieure d'un angle déterminé autour 5 d'un axe vertical avec un couple important afin de bloquer les deux tiges en fin de vissage ou les débloquer en début de dévissage, caractérisée en ce que les mâchoires de serra¬ ge d'au moins la pince supérieure, qui comprennent à une extrémité des mors destinés à être appliqués à pression sur la tige, sont Û des leviers montés à rotation autour d'un axe vertical sur le châssisTo this end, it proposes a machine for applying a torque 5 for screwing or unscrewing to rods screwed end to end, in particular vertical drilling rods, comprising two pliers respectively lower and upper each comprising a rigid frame comprising jaws clamping actuated by jacks to grip respectively 0 the upper part of a lower rod and the lower part of an upper rod, the lower clamp being fixed in rotation about the axis of the rods and means being provided for rotate the upper clamp relative to the lower clamp by a determined angle around a vertical axis with a high torque in order to block the two rods at the end of screwing or unlock them at the start of unscrewing, characterized in that the clamping jaws of at least the upper clamp, which comprise at one end jaws intended to be applied under pressure to the rod , are Û levers mounted for rotation about a vertical axis on the chassis
.rigide de la pince, et en ce que les vérins d'actionneirent de ces mâchoir - sont montés d'une part à rotation autour d'un axe vertical sur le châssis rigide et, d'autre part, à rotation autour d'un autre axe vertical sur le leviers correspondants, l'une des mâchoires de serrage étant auto-blocant sur la tige pour un sens déterminé de rotation de la pince par rapport à l'axe de la tige, et une autre mâchoire étant autoblocante sur la tige pour le sens inverse de rotation..rigid of the clamp, and in that the actuating cylinders of these jaws - are mounted on the one hand to rotate about a vertical axis on the rigid frame and, on the other hand, to rotate around a another vertical axis on the corresponding levers, one of the clamping jaws being self-locking on the rod for a determined direction of rotation of the clamp relative to the axis of the rod, and another jaw being self-locking on the rod for the opposite direction of rotation.
OMP Ainsi, selon l'invention, toute tendance au glissement de la pince supérieure serrée sur l'extrémité inférieure de la tige, qui pourrait se produire en raison d'un décentre¬ ment de la pince supérieure, renforce automatiquement le blocage et le serrage d'une mâchoire sur la tige, ce qui interdit tout glissement.OMP Thus, according to the invention, any tendency for the upper clamp to slide tightly on the lower end of the rod, which could occur due to a decentring of the upper clamp, automatically reinforces the blocking and the tightening of the upper clamp. '' a jaw on the rod, which prevents any slipping.
Selon une autre caractéristique de l'invention, la tangente horizontale à la surface périphérique de la tige dans la zone d'application du mors d'une mâchoire sur la tige, s'étend entre la tiσe et l'axe de rotation de cette mâchoire sur le châssis de la pince et passe au voisinage immédiat de cet axe de rotation.According to another characteristic of the invention, the horizontal tangent to the peripheral surface of the rod in the area of application of the jaw of a jaw on the rod, extends between the tiσe and the axis of rotation of this jaw on the clamp frame and passes in the immediate vicinity of this axis of rotation.
Grâce à cette disposition, l'interaction entre les vérins d'actionnement des mâchoires de serrage, lors de la rotation de la pince, est rendue négligeable. La machine selon l'inven tion peut ainsi fonctionner correctement même si les vérins d'actionnement des mâchoires de serrage ne sont pas parfai- tentent purgés.Thanks to this arrangement, the interaction between the actuating jacks of the clamping jaws, during the rotation of the clamp, is made negligible. The machine according to the invention can thus function correctly even if the actuating cylinders of the clamping jaws are not completely purged.
Dans la description qui suit, faite à titre d'exemple, on se réfère aux dessins annexés, dans lesquels :In the description which follows, given by way of example, reference is made to the appended drawings, in which:
les figures 1 et 2 représentent schématiquement, en vue en plan et en vue en élévation, une machine selon la technique antérieure;Figures 1 and 2 schematically show, in plan view and in elevation view, a machine according to the prior art;
la figure 3 est une vue schématique en plan.avec arrachement partiel, d'une partie d'une machine selon l'invention;Figure 3 is a schematic plan view with partial cutaway, of a part of a machine according to the invention;
la figure 4 est une vue partielle en coupe selon la ligne IV-IV de la figure 3.FIG. 4 is a partial sectional view along the line IV-IV of FIG. 3.
On se réfère d'abord aux figures 1 et 2. représentant sché¬ matiquement la technique antérieure. Dans ces fiσures, la référence 10 désigne la partie inférieure d'une tige supérieu de forage, munie d'un embout mâle de connexion 12 à filetage extérieur, et la référence 14 désigne la partie supérieure d'une tige inférieure, munie d'un .embout femelle 16 de connexion à filetaσe intérieur. Une pince inférieure 18. fixe en rotation par rapport à l'axe vertical des tiges 10 et 14, est serrée sur l'embout femelle 16 de la tige 14. tandis qu'une pince 20, mobile en rotation autour de l'axe des tiges, est serrée sur l'embout 12 de la ti e 10. Des vérins hvdrauliques, non représentés, permettent de faire tourner la pince supérieure 20 autour de l'axe 13 des tiges d'un angle déterminé avec un couple important, pour bloquer les tiges l'une sur l'autre en fin de vissage et les débloquer en début de dévissage.Reference is first made to FIGS. 1 and 2. sché¬ matically representing the prior art. In these fiσures, the reference 10 designates the lower part of an upper rod drilling, provided with a male connection end piece 12 with external thread, and the reference 14 designates the upper part of a lower rod, provided with a female end piece 16 connection with internal thread. A lower clamp 18. fixed in rotation relative to the vertical axis of the rods 10 and 14, is clamped on the female end-piece 16 of the rod 14. while a clamp 20, movable in rotation around the axis of the rods, is clamped on the end piece 12 of the rod 10. Hydraulic jacks, not shown, allow the upper clamp 20 to rotate around the axis 13 of the rods by a determined angle with a significant torque, to block the rods one on the other at the end of the screwing and unlock them at the start of the unscrewing.
Comme représenté schématiquement en figure 2, la pince supé¬ rieure 20 comprend un châssis rigide 22 sensiblement en U, entourant sur trois côtés l'embout 12 de la tige 10. Ce châssis 22 porte un ou deux mors fixes 24 et deux mors mobi¬ les 26 montés aux extrémités des tiges de piston de deux vérins hydrauliques 28 orientés radialement vers l'axe 13 des tiges.As shown diagrammatically in FIG. 2, the upper clamp 20 comprises a rigid chassis 22 substantially in a U shape, surrounding on three sides the end piece 12 of the rod 10. This chassis 22 carries one or two fixed jaws 24 and two mobi¬ jaws the 26 mounted at the ends of the piston rods of two hydraulic cylinders 28 oriented radially towards the axis 13 of the rods.
La pince supérieure 20 est montée flottante dans un plan horizontal de façon à pouvoir se centrer automatiquement sur l'axe 13 des tiges lorsque les vérins 28 sont alimentés en liquide hydraulique sous pression. Comme indiqué dans ce qui précède, les forces de poussée radiale développées par les deux vérins 28 ne sont pas toujours, en pratique, stric¬ tement égales l'une à l'autre et, lorsque la pince supérieure 20 est entraînée en rotation autour de l'axe 13 des tiges, la force développée par l'un des vérins 28 agit sur l'autre vérin, d'où un risque de décentrement de la pince 20 par rapport aux tiges de forage et de glissement des mors de cette pince sur l'embout 12 de la tige supérieure 10.The upper clamp 20 is mounted floating in a horizontal plane so as to be able to center automatically on the axis 13 of the rods when the jacks 28 are supplied with hydraulic fluid under pressure. As indicated in the foregoing, the radial thrust forces developed by the two jacks 28 are not always, in practice, strictly equal to each other and, when the upper clamp 20 is rotated around the axis 13 of the rods, the force developed by one of the jacks 28 acts on the other jack, hence a risk of decentering of the clamp 20 relative to the drilling rods and of sliding of the jaws of this clamp on the end piece 12 of the upper rod 10.
L'invention qui va être décrite maintenant en référence aux figures 3 et 4 permet notamment d'éviter ces inconvénients. La machine selon l'invention comprend, comme dans la techni¬ que antérieure, une pince inférieure fixe en rotation et une pince supérieure destinée à être entraînée en rotation autour de l'axe des tiges pour le blocage en fin de vissage et le déblocage en début de dévissage.The invention which will now be described with reference to FIGS. 3 and 4 makes it possible in particular to avoid these drawbacks. The machine according to the invention comprises, as in the prior art, a lower clamp fixed in rotation and an upper clamp intended to be driven in rotation about the axis of the rods for locking at the end of screwing and unlocking in start of unscrewing.
La pince inférieure 30 est montée fixement sur un bâti ou un support inférieur, non représenté,- et comprend, d'un côté, une chape 32 de support de l'axe vertical 34 de rota- tion du cylindre 36 d'un vérin hydraulique 38 horizontal et. d'un autre côté, une chape 40 de support de l'axe vertical de rotation 42 de l'extrémité de la ticre de piston 44 d'un vérin hydraulique horizontal 46 identique au vérin 38.The lower clamp 30 is fixedly mounted on a frame or a lower support, not shown, - and comprises, on one side, a yoke 32 for supporting the vertical axis 34 of rotation of the cylinder 36 of a hydraulic cylinder 38 horizontal and. on the other hand, a yoke 40 for supporting the vertical axis of rotation 42 of the end of the piston rod 44 of a horizontal hydraulic cylinder 46 identical to the cylinder 38.
L'extrémité 48 de la tige de piston du premier vérin 38 est mobile en rotation autour d'un axe vertical 50 porté par une chape 52 du châssis rigide 54 de la pince supérieure 56, tandis que le cylindre 58 du second vérin 46 est mobile autour d'un axe vertical de rotation 60 porté par une chape 62 du châssis 54 de la pince supérieure 56. Les axes verti¬ caux de rotation 34, 42, 50, 60 des vérins 38 et 46 et des extrémités de leurs tiges de piston sont à la même distance de l'axe 13 des tiges lorsque les deux pinces sont serrées sur les embouts de connexion de ces tiges, de telle sorte que, lorsque les vérins 3 et 46 sont alimentés en pression, ils fassent tourner la pince supérieure 56 autour de l'axe vertical 13 des tiges, dans un sens ou dans l'autre.The end 48 of the piston rod of the first cylinder 38 is movable in rotation about a vertical axis 50 carried by a yoke 52 of the rigid frame 54 of the upper clamp 56, while the cylinder 58 of the second cylinder 46 is mobile about a vertical axis of rotation 60 carried by a yoke 62 of the chassis 54 of the upper clamp 56. The vertical axes of rotation 34, 42, 50, 60 of the jacks 38 and 46 and of the ends of their piston rods are at the same distance from the axis 13 of the rods when the two clamps are tightened on the connection ends of these rods, so that, when the jacks 3 and 46 are supplied with pressure, they rotate the upper clamp 56 around the vertical axis 13 of the rods, in one direction or the other.
On va décrire maintenant plus particulièrement la structure de la pince supérieure 56, étant entendu que la structure de la pince inférieure 30 est sensiblement la même.We will now describe more particularly the structure of the upper clamp 56, it being understood that the structure of the lower clamp 30 is substantially the same.
Le châssis rigide 54 de la pince supérieure 56 forme un caisson à l'intérieur duquel sont logés deux vérins hydrau- liques identiques 64 et deux mâchoires de serrage identiques 66 qui sont agencés symétriquement par rapport à un plan vertical médian 67 passant par lraxe des tiges 13. Chaque mâchoire de serrage 66 est montée en rotation autour d'un axe vertical 68 porté par le châssis 54 et comprend à une extrémité, un mors 70 propre à être appliqué sur l'embout de connexion 12 de la tige supérieure 20. A son extrémité opposée, chaque mâchoire 66 forme une chape portant l'axe vertical de rotation 72 de l'extrémité de la tige de piston du vérin 64 associé qui, à l'extrémité opposée de son cylindre, est monté à rotation autour d'un axe vertical 74 porté par le châssis 54 de la pince supérieure.The rigid frame 54 of the upper clamp 56 forms a box inside which are housed two identical hydrau- lic cylinders 64 and two identical clamping jaws 66 which are symmetrically arranged relative to a median vertical plane 67 passing through the axis r stems 13. Each clamping jaw 66 is mounted for rotation about a vertical axis 68 carried by the chassis 54 and comprises at one end, a jaw 70 suitable for being applied to the connection end piece 12 of the upper rod 20. At its opposite end , each jaw 66 forms a yoke carrying the vertical axis of rotation 72 of the end of the piston rod of the associated jack 64 which, at the opposite end of its cylinder, is mounted for rotation about a vertical axis 74 carried by the frame 54 of the upper clamp.
Comme on le voit en figure 3, les axes de rotation 74 des vérins 64 sur le châssis 54 sont voisins l'un de l'autre et les axes longitudinaux de ces deux vérins forment entre eux un angle d'environ 45°.As can be seen in FIG. 3, the axes of rotation 74 of the jacks 64 on the chassis 54 are adjacent to each other and the longitudinal axes of these two jacks form an angle of approximately 45 ° between them.
Chaque mâchoire 66 est montée de façon à être auto-bloquante sur l'embout de connexion d'une tige pour un sens déterminé de rotation de la pince supérieure par rapport à l'axe de la tige, c'est-à-dire que, quand le mors 70 d'une mâchoire est appliqué sur l'embout de la tige, la tangente horizontale à la surface cylindrique de l'embout dans la zone d'applica¬ tion du mors 70 s'étend entre cet embout et l'axe de rotation 68 de la mâchoire de serrage. Comme les deux mâchoires de serrage 66 sont symétriques par rapport au plan vertical médian 67 de la pince, une des mâchoires est auto-bloquante sur 1*embout de la tige pour un sens déterminé de rotation de la pince autour de l'axe 13 dela tige et l'autre mâchoire est auto-bloquante dans le sens opposé de rotation autour de cet axe.Each jaw 66 is mounted so as to be self-locking on the connection end piece of a rod for a determined direction of rotation of the upper clamp relative to the axis of the rod, that is to say that when the jaw 70 of a jaw is applied to the end piece of the rod, the horizontal tangent to the cylindrical surface of the end piece in the area of application of the jaw 70 extends between this end piece and the axis of rotation 68 of the clamping jaw. As the two clamping jaws 66 are symmetrical with respect to the median vertical plane 67 of the clamp, one of the jaws is self-locking on the end of the rod for a determined direction of rotation of the clamp around the axis 13 beyond rod and the other jaw is self-locking in the opposite direction of rotation about this axis.
En outre, comme la tangente horizontale précitée à la sur¬ face cylindrique de l'embout dans la zone d'application du mors 70 passe au voisinage, immédiat de l'axe vertical de rotation de la mâchoire de serrage 66, un déséquilibre des contraintes appliquées aux mors 70 sur l'embout 12 d'une tige ne produit qu'un effet négligeable sur le vérin 64 d'actionnement de la mâchoire de serrage. De façon classique, deux mors fixes 76 sont portés par le châssis rigide 54 de la pince supérieure, par l'intermédiaire d'une pièce de fixation 78, et sont écartés angulairement l'un de l'autre de 90° environ pour être sensiblement dia é- tralement opposés aux mors 70 des mâchoires de serrage 66 quand celles-ci sont appliquées sur lrembout de connexion 12 d'une tige* In addition, as the above-mentioned horizontal tangent to the cylindrical surface of the end piece in the area of application of the jaw 70 passes in the immediate vicinity of the vertical axis of rotation of the clamping jaw 66, an imbalance of the stresses applied to the jaws 70 on the end piece 12 of a rod produces only a negligible effect on the actuator 64 for actuating the clamping jaw. Conventionally, two fixed jaws 76 are carried by the rigid frame 54 of the upper clamp, by means of a fixing piece 78, and are spaced angularly from each other by approximately 90 ° so as to be substantially dia e- tralement opposite to the jaws 70 of the clamping jaws 66 when these are applied to the r connection end 12 of a rod *
Avantageusement, l'axe de rotation 68 de l'une des mâchoires de serrage 66 se termine à sa partie inférieure par un doigt cylindrique, qui est reçu et guidé dans une rainure incurvée 80 formée dans la face horizontale supérieure du châssis de la pince inférieure 30 et qui est centrée sur l'axe 13 des tiges.Advantageously, the axis of rotation 68 of one of the clamping jaws 66 ends at its lower part by a cylindrical finger, which is received and guided in a curved groove 80 formed in the upper horizontal face of the chassis of the lower clamp. 30 and which is centered on the axis 13 of the rods.
De f çon générale, la machine selon l'invention, comprenant les pinces inférieure 30 et supérieure 56, est utilisée comme dans la technique antérieure. Toutefois, toute tendance au glissement est supprimée et les vérins 64 d'actionnement des mâchoires de serrage n'ont plus d'action l'un sur l'autre même si les vérins ne sont pas parfaitement purgés, et si un des embouts est légèrement ovalisé, de sorte que la machi¬ ne selon l'invention est beaucoup plus fiable que les machines correspondantes de la technique antérieure.In general, the machine according to the invention, comprising the lower 30 and upper 56 clamps, is used as in the prior art. However, any tendency to slip is eliminated and the actuators 64 for actuating the clamping jaws no longer have an action on each other even if the actuators are not perfectly purged, and if one of the end pieces is slightly ovalized, so that the machine according to the invention is much more reliable than the corresponding machines of the prior art.
La machine selon l'invention fonctionne de façon satisfai¬ sante avec des tiges ayant des diamètres extérieurs diffé¬ rents, compris par exemple entre 7 et 22 cm. The machine according to the invention operates satisfactorily with rods having different outside diameters, for example between 7 and 22 cm.

Claims

Revendications. Claims.
1. Machine pour appliquer un couple de vissage ou de dévissa ge à des tiges vissées bout à bout, en particulier des tiges verticales de forage, comprenant deux pinces respectivement inférieure et supérieure comprenant chacune un châssis rigid portant des;.mâchoires de serrage actionnées par des vérins pour saisir respectivement la partie supérieure d'une tige inférieure et la partie inférieure d'une tige supérieure, la pince inférieure étant fixe en rotation autour de l'axe des tiges et des moyens étant prévus pour faire tourner la pince supérieure par rapport à la pince inférieure d'un angl déterminé autour d'un axe vertical avec un couple important afin de bloquer les deux tiges en fin de vissage ou les débloquer en début de dévissage, caractérisée en ce que les mâchoires de serrage (66) d'au moins la pince supérieure (56) , comprenant à une extrémité des mors (70) destinés à être appliqués sur la tige, sont chacune montées à rotation autour d'un axe vertical (68) sur le châssis rigide (54) de la pince, et en ce que les vérins (64) d'actionnement de ces mâchoires sont chacun montés à rotation d'une part autour d'un axe vertical (74) sur le châssis rigide et, d'autre part, autour d'un axe vertical (72) sur la mâchoire correspondante, l'une de ces mâchoires étant auto-bloquante sur la tige pour un sens déterminé de rotation de la pince (56) autour de l'axe de la tige et une autre mâchoire étant auto-blocante sur la tige pour le sens inverse de rotation.1. Machine for applying a screwing or unscrewing torque to screwed rods end to end, in particular vertical drilling rods, comprising two pliers respectively lower and upper each comprising a rigid frame carrying;. Clamping jaws actuated by jacks for gripping respectively the upper part of a lower rod and the lower part of an upper rod, the lower clamp being fixed in rotation about the axis of the rods and means being provided for rotating the upper clamp relative to the lower clamp of an angled determined around a vertical axis with a large torque in order to block the two rods at the end of screwing or unlock them at the start of unscrewing, characterized in that the clamping jaws (66) of at least the upper clamp (56), comprising at one end jaws (70) intended to be applied to the rod, are each mounted to rotate around a n vertical axis (68) on the rigid frame (54) of the clamp, and in that the actuators (64) for actuating these jaws are each mounted to rotate on the one hand around a vertical axis (74) on the rigid frame and, on the other hand, around a vertical axis (72) on the corresponding jaw, one of these jaws being self-locking on the rod for a determined direction of rotation of the clamp (56) around the axis of the rod and another jaw being self-locking on the rod for the opposite direction of rotation.
2. Machine selon la revendication 1, caractérisée en ce que, pour chaque mâchoire de serrage (66) , la tangente horizon¬ tale à la surface périphérique de la tige dans la zone d'ap¬ plication du mors (70) de cette mâchoire, s'étend entre la tige et l'axe de rotation (68) de la mâchoire sur le châssis (54) de la pince.2. Machine according to claim 1, characterized in that, for each clamping jaw (66), the tangent horizon¬ tal to the peripheral surface of the rod in the area of ap¬ plication of the jaw (70) of this jaw , extends between the rod and the axis of rotation (68) of the jaw on the frame (54) of the clamp.
3. Machine selon la revendication 2, caractérisée en ce que ladite tangente horizontale s'étend au voisinage immédiat3. Machine according to claim 2, characterized in that said horizontal tangent extends in the immediate vicinity
Figure imgf000011_0001
OM de l'axe de rotation (68) de la mâchoire (66) .
Figure imgf000011_0001
OM of the axis of rotation (68) of the jaw (66).
4. Machine selon l'une des revendications précédentes, caractérisée en ce que l'axe de rotation (68) d'une des mâchoires (66) de la pince supérieure est prolongé vers le bas par un téton propre à être reçu et guidé dans une rainure incurvée (80) de la face supérieure du châssis de la pince inférieure (30) .4. Machine according to one of the preceding claims, characterized in that the axis of rotation (68) of one of the jaws (66) of the upper clamp is extended downwards by a stud capable of being received and guided in a curved groove (80) on the upper face of the chassis of the lower clamp (30).
5. Machine selon l'une des revendications précédentes, ca¬ ractérisée en ce que le châssis (54)' de la pince supérieure ou de chaque pince est un caisson dans lequel sont logés les mâchoires de serrage (66) et leurs vérins d'actionnement (64).5. Machine according to one of the preceding claims, ca¬ characterized in that the frame (54) ' of the upper clamp or each clamp is a box in which are housed the clamping jaws (66) and their jacks actuation (64).
6. Machine selon l'une des revendications précédentes, carac¬ térisée en ce que la pince supérieure (56) est reliée à la pince inférieure (30) par des bras articulés autour d'axes verticaux, permettant un centrage de la pince supérieure (56) sur l'axe (13) des tiges, deux de ces bras étant des vérins hydrauliques horizontaux (38, 46) constituant les moyens d'entraînement en rotation de la pince supérieure (56) par rapport à la pince inférieure (30) autour de l'axe des tiges, les cylindres (36, 58) et les extrémités (44, 48) des tiges des "pistons de ces vérins étant montés à rotation autour d'axes verticaux (34, 42, 50, 60) sur la pince inférieure (30) et sur la pince supérieure (56) respectivement.6. Machine according to one of the preceding claims, characterized in that the upper clamp (56) is connected to the lower clamp (30) by arms articulated around vertical axes, allowing centering of the upper clamp ( 56) on the axis (13) of the rods, two of these arms being horizontal hydraulic cylinders (38, 46) constituting the means for driving the upper clamp in rotation (56) relative to the lower clamp (30) around the axis of the rods, the cylinders (36, 58) and the ends (44, 48) of the rods of the "pistons of these jacks being rotatably mounted around vertical axes (34, 42, 50, 60) on the lower clamp (30) and on the upper clamp (56) respectively.
OMP OMP
PCT/FR1984/000177 1983-07-28 1984-07-26 Power tong for the connection of drilling pipes WO1985000634A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
BR8406968A BR8406968A (en) 1983-07-28 1984-07-26 MACHINE FOR APPLYING A TORQUE FOR SCREWING OR UNSCREWING TO RODS, IN PARTICULAR TO DRILLING RODS
GB08507898A GB2156256B (en) 1983-07-28 1984-07-26 Power tong for the connection of drilling pipes

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR83/12449 1983-07-28
FR8312449A FR2549892B1 (en) 1983-07-28 1983-07-28 MACHINE FOR APPLYING A TIGHTENING OR UNSCREWING TORQUE TO RODS, IN PARTICULAR DRILLING RODS

Publications (1)

Publication Number Publication Date
WO1985000634A1 true WO1985000634A1 (en) 1985-02-14

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PCT/FR1984/000177 WO1985000634A1 (en) 1983-07-28 1984-07-26 Power tong for the connection of drilling pipes

Country Status (7)

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JP (1) JPS60501908A (en)
KR (1) KR850001366A (en)
BR (1) BR8406968A (en)
FR (1) FR2549892B1 (en)
GB (1) GB2156256B (en)
NO (1) NO851243L (en)
WO (1) WO1985000634A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU573332B2 (en) * 1985-03-15 1988-06-02 W-N Apache Corporation Drilling tubular elevator including means for defining a passageway for passing drilling mud from a power swivel into the tubular
CN103161414A (en) * 2013-03-26 2013-06-19 重庆松藻煤电有限责任公司 Safe dismantling device of smooth round drill pipe and method thereof

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2989413B1 (en) 2012-04-13 2014-12-19 Soletanche Freyssinet CLAMPING DEVICE AND CLAMPING DEVICE COMPRISING SUCH A THRUST
CN113102988B (en) * 2021-05-24 2021-09-21 瑞安市中力门窗五金有限公司 Automatic screw equipment of beating of door and window hasp

Citations (6)

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Publication number Priority date Publication date Assignee Title
US2737839A (en) * 1952-06-02 1956-03-13 Joy Mfg Co Tongs for coupling and uncoupling drill pipe joints
GB897572A (en) * 1959-05-20 1962-05-30 Dowty Rotol Ltd Improvements relating to a unit for tightening and loosening a screwed pipe joint inearth boring equipment
FR1605191A (en) * 1967-12-26 1973-04-16
FR2269631A1 (en) * 1974-05-02 1975-11-28 Varco Int
US4082017A (en) * 1975-01-07 1978-04-04 Eckel Manufacturing Co. Power operated drill pipe tongs
GB2049518A (en) * 1979-04-30 1980-12-31 Eckel Mfg Co Back-up power tongs

Family Cites Families (1)

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Publication number Priority date Publication date Assignee Title
FR1505761A (en) * 1966-12-16 1967-12-15 Vp Izyskatelskij Ini Gidroproe Well drilling pipe train operating mechanism

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2737839A (en) * 1952-06-02 1956-03-13 Joy Mfg Co Tongs for coupling and uncoupling drill pipe joints
GB897572A (en) * 1959-05-20 1962-05-30 Dowty Rotol Ltd Improvements relating to a unit for tightening and loosening a screwed pipe joint inearth boring equipment
FR1605191A (en) * 1967-12-26 1973-04-16
FR2269631A1 (en) * 1974-05-02 1975-11-28 Varco Int
US4082017A (en) * 1975-01-07 1978-04-04 Eckel Manufacturing Co. Power operated drill pipe tongs
GB2049518A (en) * 1979-04-30 1980-12-31 Eckel Mfg Co Back-up power tongs

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU573332B2 (en) * 1985-03-15 1988-06-02 W-N Apache Corporation Drilling tubular elevator including means for defining a passageway for passing drilling mud from a power swivel into the tubular
CN103161414A (en) * 2013-03-26 2013-06-19 重庆松藻煤电有限责任公司 Safe dismantling device of smooth round drill pipe and method thereof

Also Published As

Publication number Publication date
GB2156256A (en) 1985-10-09
KR850001366A (en) 1985-03-18
GB2156256B (en) 1986-05-29
BR8406968A (en) 1985-06-11
JPS60501908A (en) 1985-11-07
GB8507898D0 (en) 1985-05-01
NO851243L (en) 1985-03-27
FR2549892A1 (en) 1985-02-01
FR2549892B1 (en) 1985-10-18

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