EP0376811A1 - Remote actuator with a nozzle-needle system - Google Patents

Abstract

The present invention relates to a remote actuator for a piece of equipment, operating by variation in the flow conditions of a possibly incompressible fluid, comprising an actuating piston (12) and a nozzle-needle unit (20, 21; 53, 57). This actuator is characterised in that one of these two elements (20, 21; 53, 57) is mounted so as to slide in the said piston (12), and in that it comprises means (24) for returning the said slidably mounted element to a predetermined position relative to the said cylinder. <IMAGE>

Description

The present invention relates to a device for remote actuation of equipment used in connection with conduits in which a fluid circulates.

In the field of oil drilling, it is often necessary to actuate tools located in the drilled well remotely.

The actuation of such tools requires high powers.

According to the prior art, an annular piston having two faces and a throttle member comprising a needle nozzle with variable passage section is used. One side of this piston is subjected to the pressure forces existing on one side of the throttle member, the other face is subjected to the pressure forces existing on the other side of the throttle member.

Generally, the nozzle is carried by the piston and the needle is fixed relative to a conduit containing the assembly and in which the piston can move to effect the desired actuation. The piston has return means which keep it in a rest position corresponding to a relatively large cross-section of the throttle member causing a low pressure drop for service flows.

When it is desired to actuate the equipment, the flow is increased, which increases the pressure drop on either side of the throttle member and therefore the piston tends to move while thwarting the return members . In this movement, the nozzle enters more and more into the needle resulting in the decrease in the cross-section of the throttle member, hence an increase in the greater pressure drop providing the power for the actuation of equipment.

The prior art can be illustrated by patent FR-2,575,793.

However, such a device has a lack of precision with regard to the threshold flow rate causing the actuation to be triggered. In fact, the assembly constituted by the piston and the return spring, which must react to or transmit significant powers, cannot be sensitive to a given flow threshold in a precise manner, this for example due to friction forces .

The present invention solves this problem by using a nozzle or a needle carried by the piston, but movable relative to this piston.

This nozzle or needle of small size relative to the piston fitted with appropriate return means is sensitive precisely to a flow threshold.

Thus, the present invention relates to a device for the remote actuation of an item of equipment by a variation in the conditions of flow of a fluid, possibly incompressible, comprising an actuating piston, a nozzle-needle assembly.

This device is characterized in that one of these two elements is slidably mounted in said piston and in that it comprises return means for said element slidably mounted in a predetermined position relative to the piston.

The element mounted to slide in said piston could alternatively be either the nozzle or the needle, one excluding the other.

The needle may be hollow and include lights which cooperate with other lights carried by said nozzle.

The apertures may have a shape adapted to gradually reduce the cross-section of the fluid passage over a portion of the travel of said needle.

• - les figures 1, 1A et 1B représentent un mode de réalisation du dispositif duse-aiguille selon la présente invention,
• - les figures 2 et 3 montrent un équipement à actionner qui est un élément coudé à angle variable,
• - la figure 4 illustre un équipement à actionner qui est un stabilisateur à géométrie variable,
• - la figure 5 représente un détail du système d'entraînement de tiges permettant la flexion de ces tiges,
• - les figures 6, 6A et 6B représentent un autre mode de réalisation du dispositif selon l'invention, et
• - les figures 7 et 8 montrent une forme particulière de lumières aménagée dans le système duse-aiguille.

The present invention will be better understood and its advantages will become more clearly apparent from the following description of particular, non-limiting examples illustrated by the appended figures, among which:

• FIGS. 1, 1A and 1B represent an embodiment of the needle-needle device according to the present invention,
• - Figures 2 and 3 show an equipment to be actuated which is a bent element with variable angle,
• FIG. 4 illustrates an item of equipment to be actuated which is a stabilizer with variable geometry,
• FIG. 5 represents a detail of the rod drive system allowing the bending of these rods,
• FIGS. 6, 6A and 6B represent another embodiment of the device according to the invention, and
• - Figures 7 and 8 show a particular form of lights arranged in the nozzle-needle system.

Figures 1 to 5 show exemplary embodiments of the device according to the present invention applied to the control of a variable geometry stabilizer, or a variable angle bent element.

• A. par le moteur de fond 5 représenté sur la figure 2 sous forme d'un moteur volumétrique multilobes de type Moineau, mais pouvant être tout type de moteur de fond (volumétrique ou turbine) couramment utilisé pour la foration terrestre et qui ne feront donc pas l'objet d'une description détaillée.
• B. par un mécanisme de télécommande 6 ayant pour fonction de capter l'information de changement de position et de provoquer la rotation différentielle du corps tubulaire 7 relativement au corps tubulaire 8.
• C. par un mécanisme 9 d'entraînement et d'encaissement des efforts axiaux et latéraux reliant le moteur de fond 5 à l'arbre de sortie 3 qui ne sera pas décrit ici, car il est connu de l'homme de métier.
• D. par un mécanisme de variation de la géométrie 10 basé sur la rotation du corps tubulaire 7. La référence 11 désigne un joint universel. Celui-ci est utile lorsque le moteur est de type Moineau ou/et lorsqu'il est utilisé un élément coudé 10.

Figures 1, 2 and 3 show a particularly advantageous embodiment of a variable angle bent element. According to this embodiment, a tubular element has in its upper part a thread 1 allowing the mechanical connection to the drill string and in its lower part a thread 2 on the output shaft 3, in order to screw the tool drilling 4. The main functions are ensured:

• A. by the downhole motor 5 represented in FIG. 2 in the form of a multi-lobe volumetric motor of the Sparrow type, but which can be any type of downhole motor (volumetric or turbine) commonly used for land drilling and which therefore will not not the subject of a detailed description.
• B. by a remote control mechanism 6 having the function of picking up the information of change of position and of causing the differential rotation of the tubular body 7 relative to the tubular body 8.
• C. by a mechanism 9 for driving and collecting the axial and lateral forces connecting the downhole motor 5 to the output shaft 3 which will not be described here, as it is known to those skilled in the art.
• D. by a mechanism for varying the geometry 10 based on the rotation of the tubular body 7. The reference 11 designates a universal joint. This is useful when the motor is of the sparrow type and / or when a bent element 10 is used.

The remote control mechanism consists of a shaft 12, forming a piston, which can slide in its upper part in the bore 13 of the body 8 and can slide in its lower part in the bore 14 of the body 7. This shaft has grooves male 15 meshing in female grooves of the body 8, grooves 16 alternately straight (parallel to the axis of the tubular body) and oblique (inclined with respect to the axis of the tubular body 8) in which fingers 17 engage sliding along an axis perpendicular to that of the displacement of the shaft 12 and kept in contact with the shaft by springs 18, male splines 19 meshing with female splines of the body 7 only when the shaft 12 is in the high position.

The shaft 12 is equipped in its lower part with a bore 20 opposite which is a needle 21 coaxial with the movement of the shaft 12. A return spring 22 maintains the shaft in the high position, the splines 19 meshing in the equivalent female grooves of the body 7.

According to the present invention, the nozzle 20 is slidably mounted in a housing 23 integral with the shaft 12.

The bodies 7 and 8 are free to rotate at the level of the rotating surface 30 coaxial with the axes of the bodies 7 and 8 and composed of rows of cylindrical rollers 31 inserted in their raceways and extractable through the orifices 32 by dismantling the door 33.

The nozzle 20 and the needle 21 form means for detecting information in this case a flow threshold. The shaft 12 with its arrangements constitutes the power means for activating the bent element 9 via the tubular body 7 which constitutes a transmission element.

A reserve of oil 34 is maintained at the pressure of the drilling fluid by means of an annular free piston 35. The oil lubricates the sliding surfaces of the shaft 12 via the passage 36.

The shaft 12 is machined so that an axial bore 79 allows the passage of the drilling fluid according to the arrow f.

A spring 24 keeps the usage 20 in a high position which corresponds to a rest position. This position is considered relative to the shaft 12. The spring 24 bears on a collar 25 integral with the bore 20 on the one hand, and on a shoulder 26 integral with the shaft 12. In the case of FIG. 1, the guidance of the bore is ensured by a bore 27 in which the collar 25 slides as well as by the circular body 28 of the bore which slides in the orifice 29.

The angle variation mechanism itself which is the member to be actuated in this example comprises a tubular body 38 which is rotationally integral with the tubular body 7 by means of a coupling 39. The tubular body 38 can rotate relative to the tubular body 8 at the level of the rotating surface 10 comprising rollers 39A and having an oblique axis with respect to the axes of the tubular bodies 8 and 38.

A possible embodiment for the coupling 39 is shown in FIG. 5.

The operation of the remote control mechanism is described below. This type of remote control is based on a threshold value of the flow through the mechanism according to the arrow f.

When a flow Q crosses the shaft 12 there occurs a pressure difference Δ P between the upstream part 40 and the downstream part 41 of the nozzle or nozzle 20. This pressure difference increases when the flow Q increases according to a law of variation of the type Δ P = kQ ⁿ , k being a constant and n ranging between 1.5 and 2.0 according to the characteristics of the drilling fluid. This pressure difference Δ P applies to the section S of the nozzle 20 and creates a force F tending to move the nozzle 20 downwards by compressing the return spring 24. For a threshold value of the flow rate this force F will become large enough to overcome the return force of the spring and cause a translation of the usage 20. The calibration of the spring 24 is adjusted as a function of the flow threshold value which it is desired to obtain.

Due to this translation, the nozzle 20 will surround the needle 21 which will cause a large decrease in the cross-section of the drilling fluid and therefore a large increase in the pressure difference Δ P and therefore a significant increase in the force F ′ exerted on the shaft 12 and ensuring the complete descent of this shaft 12, despite the increase in the return force of the spring 22 due to its compression and to the friction forces opposing its movement.

Thus, it appears that it is the only displacement of the movable bore 20 without the displacement of the shaft 12, as illustrated in FIG. 3, which precisely detects the flow threshold value and subsequently causes a significant loss load causing the descent of the shaft 12, as shown in Figure 4. This descent of the shaft 12 actuates equipment such as a variable angle elbow. Thus, mobile usage acts in a way like an electrical relay.

Due to the shape of the machining of the grooves 16 described in patent FR-2,432,079, the fingers 17 will follow the oblique part of the grooves 16 during the downward stroke of the shaft 12 and will therefore cause the body to rotate tubular 7 relative to the tubular body 8, which is made possible by the fact that the male splines 19 will disengage from the corresponding female splines of the body 7 at the start of the downward stroke of the shaft 12.

The shaft having arrived at the bottom stop, cutting the flow will allow the return spring 22 to push the shaft 12 upwards. It is the same for the usage 20 which is pushed upwards by the return spring 24.

The fingers 17 will follow, during this ascending stroke, the rectilinear parts of the grooves 16. At the end of the race, the grooves 19 will engage again in order to secure in rotation the tubular bodies 7 and 8.

In order to transmit surface information indicating that the shaft 8 has reached its low position, the needle 21 may include a variation in diameter. In the case of FIG. 1, there is an increase in diameter 44. Thus when the nozzle arrives at this protuberance 44 there is a reduction in the cross-section of the fluid which results in a constant flow rate. overpressure in the drilling fluid.

This overpressure is detectable on the surface. The position of the protrusion 44 is such that the overpressure only appears when the shaft 12 is at the low end of travel.

FIG. 5 is a developed illustration of parts 42 and 43 which make it possible to transmit the rotation of the tubular body 7 to the tubular body 38 while allowing relative angular movement of these two tubular bodies.

The part 42 comprises housings 45 in which rods 46 having spheres 47 come to cooperate. Thus, although the tubular body integral with the part 42 flexes relative to the tubular body integral with the part 43. There is a rotation drive of a body tubular or the other. Thus these two parts have the same role as a hollow universal joint.

The variation of the angle is obtained by the rotation of the tubular body 7 relative to the tubular body 8 which causes, through the drive mechanism 39, the rotation of the tubular body 38 relative to this same tubular body 8. This rotation is doing around an axis oblique to the two axes of the bodies 8 and 38 will cause a change in the angle formed by the axes of the bodies 8 and 38. This change in angle is detailed in patent FR-2,432,079. Figure 3 shows the same part of the device as that shown in Figure 2, but in a geometrically different position.

An embodiment is now described in which the member to be actuated is a stabilizer with variable geometry. The remote control mechanism of this stabilizer is the same as that described above.

FIG. 4 describes the mechanism for varying the position of one or more blades of an integrated stabilizer. Figure 4 can be considered as the lower part of Figure 1.

Grooves 48 are machined at the lower end of the body 7, the depth of which differs according to the angular sector concerned. Apply to the bottom of these grooves pushers 49 on which rest blades 50 straight or helical in shape under the action of leaf return springs 51 positioned under protective covers 52.

The operation of the position variation mechanism of one or more blades is shown below.

During the rotation of the tubular body 7 relative to the tubular body 8 caused by the displacement of the shaft 12, the pushers 49 will be on a sector of the groove 48 whose depth will be different. This will cause a translation of the blades, either by moving away, or by approaching the axis of the body.

Figure 4 shows on the right side a blade in the "retracted" position and on the left side a blade in the "extended" position. Several intermediate positions are possible, depending on the angular rotation pitch of the remote-controlled rotation mechanism.

It is the profile of the bottom of the groove 48 which controls the position of the blades. If three blades are ordered from the same groove and on a lathe, the profile is reproduced identically every 120 degrees if the movement of the three blades must be identical.

FIGS. 6, 6A and 6B correspond respectively to FIGS. 1, 1A and 1B as regards the position of the shaft 12 as well as the state of the nozzle-needle system.

However, in these figures, the needle 53 is integral with the shaft 12 and has a passage 54. This needle which is therefore hollow, has slots 55 which cooperate with slots 56 formed in the nozzle 57 which is integral with the body tubular 7.

In FIG. 6, the nozzle 57 is cylindrical and has a closed bottom 58. The needle 53 which is also cylindrical, slides in the nozzle 57.

In the initial position, the apertures 55 of the needle 53 and 56 of the nozzle 57 are opposite and the fluid flows in the direction of the arrows f (Fig. 6).

When a predetermined flow threshold is reached, the pressure difference between the upstream 40 and downstream 41 zones on either side of the needle-nozzle system increases, needle 53 included, spring 24 (Fig. 6) without qu 'there is still displacement of the piston 12.

The passage section left to the fluid due to the cooperation of the lights 55 and 56 decreases and is limited to the clearance between the needle and the nozzle, this is the case in FIG. 6A.

In doing so, the pressure difference between the upstream 57 and 41 of the piston 12 increases sufficiently to actuate the piston 12 which descends to occupy the position shown in FIG. 8.

During this descent, he will have activated the equipment to be controlled.

FIGS. 9 and 10 show in a developed manner, particular shapes of lights 59 of the nozzle 57. These shapes make it possible to achieve a progression of the passage section left to the fluid when the needle 53 moves in the nozzle 57.

Of course, these lights may have a particular shape to indicate that the shaft 12 has reached the end of its travel, this is obtained in the case of the light shown in FIG. 7 when the light 55 supposed to be rectangular exceeds the bottom part 60 of the light 59 of the nozzle 57. In this case, there is an abrupt change in pressure detectable on the surface.

Claims (6)

1. - Device for the remote actuation of an item of equipment by varying the flow conditions of a fluid, possibly incompressible, comprising an actuating piston (12), a needle-needle assembly (20, 21; 53 , 57), characterized in that one of these two elements (20, 21, 53, 57) is slidably mounted in said piston (12) and in that it comprises return means (24) of said mounted element sliding in a predetermined position relative to said piston. 2. - actuation device according to claim 1, characterized in that said element mounted sliding in said piston is the nozzle (Fig. 1). 3. - Device according to claim 1, characterized in that said element mounted sliding in said cylinder is the needle (Fig. 6). 4. - Device according to claim 3, characterized in that said needle (53) is hollow and comprises lights (55) which cooperate with other lights (56) carried by said nozzle (57). 5. - Device according to claim 4, characterized in that said slots (55, 56 and 59) have a shape adapted to gradually reduce the fluid passage section over a portion of the stroke of said needle (53). 6. - Device according to one of claims 4 or 5, characterized in that said lights have a shape adapted to create a variation in section when said piston reaches a low position.

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