FR2597544A1 - Device for anchoring a measuring and recording instrument on the walls of a well - Google Patents

Abstract

The invention relates to the field of measurement for monitoring an oil-producing well. The device comprises a clock mechanism, a hydraulic lock, a laying tool and an anchoring block which comprises anchoring blades 70 articulated to the two ends by a pair of connection rods 74, 76 and arranged in a protective casing 72, one end of the connection rods 74 being fixed to a first sliding assembly comprising an external casing 38 and the other end 77 of the connection rods being fixed to a hollow shaft 80 coaxial with the said casing. The external casing 38 is fixed to the connection rods via a housing 50 with inclined ramps 55 for the catches 51, whereas the upper end of the hollow shaft 80 bears on the free end of catches forced open by a spring 54. The invention makes it possible to position recorders in wells and to leave them in position by removing the winch cable and then to fish them out by means of a suitable tool.

Description

The present invention relates to an anchoring device on the cased walls of a well at a determined height of an item of equipment such as a measuring and recording apparatus, making it possible to leave such equipment in place, without that it is permanently supported by suspension means from the surface.

In oil or gas producing wells, measurements are regularly made to control a certain number of parameters essential for monitoring the deposit. Measuring instruments are usually lowered into the well by means of a winch cable, positioned at a given level and left in place for the time necessary to enter information, for example pressure measurements, then reassembled by means of the same cable, when the measurements are completed.

In some cases, the cable is removed for safety reasons, leaving the measuring instruments in the well, also because of the risk involved in reassembling them.

The disadvantage of this technique lies in the fact that the measuring instruments are always placed at the same level and that, when it is a question of positioning them at the level of the perforations, the risks of loss of the equipment are significant, as long with regard to the material as the entire facility and the environment.

There is therefore a need to have means for recording to be carried out without requiring the permanent support, in place, of the support system for the measurement and recording equipment at the bottom of the well.

Such a recording method is especially important when dealing with deposits in the process of depletion for which any measurement entered is incomparably more precise than a calculation by extrapolation.

The present invention therefore relates to a device for positioning the recorders in a cased well, in line with perforations, by passing this equipment through casings of various diameters, and of being able to leave them in place, by removing the cable from the winch, then to fish them out using a suitable fishing tool.

The device according to the invention comprises a clock system, a setting tool for setting up the equipment or a recovery tool for recovering the equipment controlled by said clock system and a set of anchoring and locking, in particular making it possible to keep the device in place and to avoid its descent under the weight of the equipment or its ascent under the effect of the pressure of the effluent produced by the well.

The anchoring system itself ensures good stability of the assembly and perfect centering in the axis of the well.

The anchoring device on the walls of a well according to the invention is characterized in that it comprises a clockwork mechanism, a setting or recovery tool and an anchoring and locking block, said block comprising anchor blades articulated at both ends by a pair of rods and arranged in a protective casing, one end of the rods being secured to a first sliding assembly comprising an outer casing and the other end of the rods being secured to a hollow shaft coaxial with said envelope.

According to a preferred embodiment, the outer shell is secured to the rods by means of a housing with inclined ramps of the pawls, while on the free end of pawls urged in opening by a spring is supported by upper end of the hollow shaft.

Advantageously, the hollow shaft has on its outer face a support for an anchoring spring, the second fulcrum of which is a stop for a ferrule, at the upper end of which one of the connecting rods is fixed.

Preferably, the retention of the pawls and of the leaf springs is carried out by means of an external ferrule disposed inside the external envelope, said ferrule forming with said envelope an annular housing for a locking spring bearing respectively on a shoulder of the ferrule and on a shoulder of the housing of the pawls integral with the outer casing, while a central shaft passing through the outer ferrule forms a housing for balls capable of securing and detaching the ferrule and the shaft.

The fitting tool can be fixed on an inner fitting ferrule contained in the outer casing and sliding relative to the central shaft, said ferrule being provided at its lower part with notches which form with erasure grooves which is provided on the inner face of the outer shell with a housing for the balls, the central shaft being provided with a bulge of obstructing section and freeing the passage of the balls, when this bulge is at the same level as the erasure grooves.

Preferably, the hydraulic lock comprises a lock head in the central bore from which slides a piston and a piston rod, the lower part of the lock head having an enlarged section carrying a circular notch to form with erasure grooves of the casing, a housing for balls, the passage of which is obstructed or released by a bulge in cross section of the piston rod, when this bulge is at the same level as the erasure grooves, in order to secure or separate the outer jacket and the lock head.

The device according to the invention is illustrated by an embodiment presented by way of example and based on drawings, of which
Figures la, lb, lc and 1d show the device in long section
tudinal at the time of its installation in the well,
Figures 2a, 2b, 2c, 2d show the same device at the time of ac
operated by the clockwork mechanism,
Figures 3a, 3b, 3c, 3d show the same device, when accom
pulls on the winch cable to lock, and
Figures 4a, 4b, 4c, 4d show the device during unlocking.

The device is composed of a clockwork mechanism called "Amérada", a fitting and recovery tool and an anchoring and locking block.

The clockwork mechanisai A is a mechanism universally known in the petroleum field under the name of Amérada and described, for example, in French patent nO 2087013. It consists of a clock, not shown, placed in an envelope t printing a rotary movement & a threaded rod 4 rotating in a nut 3 serving as a flyweight, mounted by means of a lug 13 in a jacket 2. On the side of the lower end of the rod 4, the casing 1 contains a hollow cylinder accommodating a pressurized oil chamber 8 opening axially by means of a calibrated nozzle 9 in an axial duct hollowed out in a support 10 of a pellet 7 closing said duct. On the opposite side, in the vicinity of the patch, opens an axial channel into which is disposed a striker 6, above which is placed a mass 5 serving to support the striker 6 and sheathed with a bellows 12.

Conduits for the oil flow 11 are present in the support 10.

The operation of this mechanism is as follows.

The clock being adjusted so as to ensure the initiation of the operation within a determined period, the rod 4 by turning ensures the descent of the counterweight 3 which, released after a given period of time, falls on the shoulder or t6te striker 5, the latter transmits the impulse to the striker 6 which punctures the pellet 7. The oil under pressure contained in the chamber 8 flows through the calibrated nozzle 9 and the conduits 11 towards the interior of the bellows 12.

The whole anchoring and locking block is made up of several concentric parts which can slide relative to each other. A first concentric piece comprises an envelope 38 in the extension of which is fixed a pawl housing 50, itself integral and extended by an envelope of the pawls 60. The pawls are constituted by fingers 51 arranged concentrically and articulated around the axes 52 pivotally. The heads 53 of pawls 51 are biased in approach by spring blades 54, so that their opposite ends, when they are released from their casing 60 and come up to the level of the housings 50, move apart and come to be housed on the inclined ramp bottoms 55, with which the interior faces of housings 50 are provided.

Anchoring blades 70 three in number concentrically spaced 1200 from one another are contained in a blade protection jacket 72 provided with longitudinal slots for the passage of blades outside said jacket. These blades 70 are mounted at its two ends by articulations 73 at their upper ends to rods 74, themselves fixed by articulations 75 to the pawl casing 60 and by articulations 76 at their lower ends to rods 77 , themselves fixed to a ferrule 78 by joints 71.

Another sliding assembly is constituted by a hollow shaft 80, internal with respect to the assembly described above, and which carries on its periphery several movable stops 85 secured by screws with the shaft 80 and sliding inside the slots of which is fitted with ferrule 78.

The ferrule 78 is carried at one of its ends by a connection integral with the rods, while its other end carries a guide member
gripping.

A fixed outer jacket of the anchoring device 82 accommodates in the annular space which it forms with the ferrule 78 an anchoring spring 83 which bears, on the one hand, on a stop 84 secured to the outer jacket 82, and on the other hand, on the movable stops 85 integral with the hollow shaft 80.

The lower end of the ferrule 78 carries a gripping device 86 used for fixing the equipment to be positioned in the well and sliding relative to the hollow shaft 80.

The fitting and recovery tool part is constituted by a hydraulic lock head 20 temporarily coupled with a jacket 38 of the anchoring and locking block in the manner described below.

The lock head 20 has an axial bore, first of a restricted section in which a piston 24 slides, then of an enlarged section in which slides a rod 23 of the piston provided with a bulge of section 23a corresponding to the enlarged section of the bore.

The upper part of the bore constitutes a cylinder 25 for the piston 24 in communication with the oil pressure chamber 8 of the clockwork mechanism.

The part 22 of the latch head 20 corresponding to the enlarged section of the bore carries a circular notch 27 provided for housing the balls 29.

The hydraulic lock is supplemented by an outer casing 30 which accommodates in its annular space which it forms with the lock head a spring 32 bearing on a shoulder 33 of the lock head and exerting a thrust by means of a shoe 31 on shirt 38.

The envelope 38 is screwed onto the housing of the pawls 50. At its upper part, it forms an enlargement of section corresponding to the erasure grooves 28, which form, with the notches 27 of the lock head, the housing for the balls 29, when they are at the same level and opposite these notches.

The rod 23 of the piston has a shoulder 34 on which a spring 35 bears urging another internal fitting ring 36 contained in the casing 38 and which is temporarily secured to the central shaft 40 by means of a circlip 39 The circlip 39 is housed in an internal groove of the ferrule 36 and in an external groove of the central shaft 40, so as to temporarily prohibit the relative movement of the shaft relative to the ferrule. central 40 pushed from top to bottom abuts against the head 53 of the pawls 51, the circlip 39 emerges from the inner groove of the ferrule 36, which thus released slides downwards and the circlip 39 is found opposite the enlarged section that has the recess in the upper part of the ferrule 36 and, no longer being subjected to compression by the narrow bore of the ferrule, expands to tend towards its normal position at rest, which possibly prevents the shaft 40 from go down during man subsequent works.

The ferrule 36 is temporarily coupled with another ferrule 42 external to the first and which is in its extension, by means of balls 44. The internal ferrule 36 is fitted at its lower part with the notches 41 and is surrounded by the ferrule 42 provided opposite these notches with erasure grooves 43, when they are at the same level and when the bulge in section 40a of the shaft 40 does not obstruct the passage.

A locking spring 62 housed in the annular part between the envelope 38 and the ferrule 42 bears on the housing of the pawls 50 and the latter ferrule.

At the lower part of the ferrule 42 are fixed the spring blades 54 urging the lower ends of the pawls 51 to open.

A spring 45 is housed in the annular space between the jacket 38 and the ferrule 36 and which bears on a shoulder 37 of the ferrule and pushes back via ferrule 38 the ferrule 42.

The operation of the device is as follows.

In the operating position, the piston 24 is in the low position, the pawls 51 are blocked in the folded position in the casing 60, while the blades 70 and the rods 74, 76 are in the folded position (FIG. 1).

Under the effect of the control of the clockwork mechanism, the piston 24 rises, driving the rod 23, the bulge of section 23a ceasing to obstruct the housing of the balls 29, eliminates the blocking in position of the jacket of the installation tool 38.

The jacket -38 descends by sliding along the assembly formed by the ferrule 42, the central shaft 40 and the pawls 51 and causes the downward movement of the envelope of the pawls 60. It falls down until it is taken of the locking spring 62.

The envelope of the pawls 60, as it moves, releases the pawls, the upper ends of which open under the action of the spring blades 54 and come closer to the housing 50.

The pressure exerted on the rods 74, 76 spreads the latter, allowing the deployment of the blades which, passing through the windows located in the casing 82, move apart to come into contact with the walls of the casing tube.

A traction is exerted on the surface carrying the entire device by pulling on the latch head 20. This action has the effect of exerting a traction on the hollow shaft 80 which, by compressing the anchoring spring 83, in turn raises the ferrule 78. In turn, the connecting rod 76 moves apart, causing the blades 70 in the fully deployed position until the anchoring stops against the walls of the casing tube (FIG. 2).

The degree of tension of the spring 83 depends on the degree of plating of the blades 70.

Continuing the upward movement, the latch head 20 secured to the hollow shaft 80 causes the pawls 50 to be raised, which engage in the housings 50 at the bottom of the ramps 55 (FIG. 3).

The locking spring 62 holds the pawls firmly in place.

Depending on the traction exerted, the pawls are raised higher or lower, which makes it possible to control the degree of locking.

When it is a question of leaving the anchoring device in place without being encumbered by the cable and the fitting tool (FIG. 4), a push is exerted on the latch head 20 and on the inner ferrule 36 causing displacement of the shaft 40 by means of the circlip 39. When the end of the shaft 40 abuts against the head 53 of the pawls 51, the thrust exerted on the circlip 39 causes its release from the internal groove of the ferrule 36, which released thus slides down and releases the obstructed passage for housing the balls 44.

The ferrule 36 being separated from the ferrule 42, the fitting tool can be reassembled and there remains in the well only the anchoring block comprising, inter alia, the jacket 38, the ferrule 42 and the central shaft 40, which ensure the anchoring of the blades 70 and the locking of the pawls.

To recover the device according to the invention, it suffices to use the same setting tool. The tool is lowered into the retracted position and, possibly connected to the clockwork mechanism. This tool is fitted with centralizers that open on a clock command to center the recovery equipment on the equipment in place to be recovered.

When the mechanism is triggered, the tool head enters the shirt head 38, the descent continues for a few centimeters and the locking takes place automatically according to the conventional method.

The maneuver continuing, by exerting a slight pressure, the central rod 40 retracts and presses on the anchoring fingers by applying pressure to the springs of the pawls to open them. A traction is then exerted on the hollow shaft 80, in order to compress the anchoring spring 83.

As soon as the pawls are no longer stressed, there is release of the spring and release and release of the blades 70 and the rods which retract.

The device according to the invention is of safe and reliable operation.

It allows in particular to position the recorders at the right of the perforations, whatever the diameter of the casing lining the well.

Indeed, the same anchoring equipment can be provided with blades of different dimensions compatible with the diameter of the casing for which the equipment is intended, without modification of the basic system itself.

The equipment can be removed from the well, whatever its level, while, when it is in operation, it leaves free passage for the effluent.

Its installation is simple. At the chosen location, the clock system triggers the anchoring, while locking takes place by pulling on the winch cable.

In the case of sludge injection or flow through the equipment, the pressure drops add to the locking voltage and make it self-locking. The blocking power can be increased either by setting the springs or by using several superimposed anchor blocks.

Claims (6)

CLAIMS. 1. Anchoring device, on the walls of a well to a depth  mined, equipment, such as measuring and recording equipment  allowing the said equipment to be left in place without it being  permanently supported by suspension means from the on  face, characterized in that it comprises a clockwork mechanism, a  hydraulic lock, a setting tool and an anchor block, said block  anchor comprising anchor blades (70) articulated at the two ends  mothballed by a pair of links (74,76) and arranged in an enclosure  protective pad (72), one end of the rods (74) being so  lidaire of a first sliding assembly comprising an envelope ex  térieur (38) and the other end (77) of the rods being integral  a hollow shaft (80) coaxial with said envelope. 2. Device according to claim 1, characterized in that the envelope  outer (38) is integral with the rods by means of a  housing (50) with inclined ramps (55) of the pawls (51), while  on the free end of pawls biased in opening by a spring  (54) bears on the upper end of the hollow shaft (80). 3. Device according to claim l or 2, characterized in that the shaft  hollow (80) has on its outside face a support (85) for a spring  anchor (83), the second fulcrum of which is a stop (84) of a  ferrule (78), at the upper end of which is fixed one of the  rods (77). 4. Device according to one of claims 1 to 3, characterized in that  holding the pawls (51) and spring leaves (54) in place  is made by means of an outer ferrule (42) arranged inside  of the outer casing (38), said ferrule forming with said at  Velcro an annular housing for a locking spring (62) taking  support respectively on a shoulder of the ferrule and on a shoulder  ment of the pawl housing (50) integral with the outer casing  (38) and in that a central shaft (40) crossing the outer shell  (42) forms a housing for balls (39) capable of joining and  to separate the ferrule (42) and the shaft (40). 5. Device according to one of claims 1 to 4, characterized in that  the fitting tool is fixed on an inner fitting ferrule (36) contained  in the outer casing (38) and sliding relative to the shaft  central (40), said ferrule being provided at its lower part with  notches which form with erasure grooves (43) which is  provided on the inner face of the outer shell (42) a housing for  balls (39), the central shaft (40) being provided with a section bulge  obstructing (40a) and releasing the passage (41) of the balls, when this  bulge is at the same level as the erasure grooves (43). 6. Device according to one of claims l to 5, characterized in that  the hydraulic lock has a lock head (20) in the bore  central sage from which slides a piston (24) and a piston rod (23),  the lower part of the lock head having a section  enlarged bearing a circular notch (27) to constitute with the  erasure grooves (28) of the casing (38) a housing for  balls (29), the passage of which is obstructed or released by a bulge  section (23a) of the piston rod (23), when this bulge  is at the same level as the erasure grooves (28), in order to  secure or separate the outer jacket (38) and the head  lock (20).