Field of the Invention

The present invention relates to an apparatus and method for controlling the position of a downhole tool within a passage.

Background to the Invention

In oil drilling and other well operations a wireline may be used for raising and lowering tools into the wellbore. For example, a tool or toolstring may be attached to the end of a reel of a single strand or braided wire. The wireline passes through a stuffing box which is installed on a top of a lubricator stack. The stuffing box is used to facilitate a seal and retain well pressure around the moving or stationary wireline. During wireline operations it is desirable to know the position of the toolstring within the well. The position of the tool may be monitored but this is not always accurate. Uncertainty in the position of the toolstring may cause the toolstring to be drawn into the stuffing box which results in the wireline breaking and the toolstring being dropped into the well. The recovery process of such toolstrings can be dangerous as the wireline can be blown out and hydrocarbon leaks can occur. It can also be very time consuming and costly, for example due to production downtime. Thus, additional control of the position of the toolstring within the lubricator may be desirable.

Summary of the Invention

According to a first aspect there is provided apparatus for controlling the position of a tool in a passage comprising means for detecting the position of the tool in the passage, said detecting means being coupled to control means for moving said tool within said passage, whereby when said tool reaches a predetermined position, said detecting means sends a signal to said control means to stop further movement of said tool.

Said detection means may be provided within and/or on said passage. Said detection means may comprise a detection member pivotally mounted within said passage for pivotal movement between an open position and a closed position. The detection member may be mounted on a shaft. The shaft may project to an outer or external portion of the passage. In the closed position the detection member may partially occlude the passage. The detection member may be positioned at the predetermined position with the passage. The detection member may be coupled to the shaft so as to at least partially extend into and/or across the passage in the closed position. The detection member may be arranged on or coupled to a central portion of the shaft. Movement, such as pivotal movement, of the detection member may cause the shaft to move or rotate, e.g. rotate about a longitudinal axis of the shaft. Alternatively or additionally, movement, such as rotational movement, of the detection member may move or rotate the shaft. The detection member may extend substantially horizontally into the passage in the closed position.

In the open position, the detection member may be deflected or deflectable in a downwards or upwards direction with respect to the passage. In the open position, the detection member may be aligned or extend in line with a longitudinal axis of the passage. The passage may be adapted to comprise or define a recess, in which the detection member may be provided in the open position.

In some examples, the detection member may comprise at least one elongate member or finger. In other examples,, the detection member may comprise a valve, such as a flapper valve, adapted to permit passage of a wire or wireline.

In some examples, the apparatus may comprise one or more resilient member(s) for maintaining or biasing the detection member into the closed position. The one or more resilient member(s) may be coupled to or arranged on the shaft and/or engage an external portion of the passage. For example, the one or more resilient member(s) may comprise one or more spring(s) or torsion spring(s).

The apparatus may comprise a coupling arrangement.

The detection means may further comprise the coupling arrangement for linking said detection means to said control means. Said coupling arrangement may comprise an actuable member, such as a piston or double acting piston, and/or a further elongated member, e.g. a cam lug, provided on said outer or external portion of said passage. Alternatively or additionally the actuable member may comprise a valve, such as a poppet valve or the like. Said further elongate member may be provided on said shaft. Said further elongate member may be linked to the movement of said detection member by said shaft such that, for example, in said closed position of said detection member said further elongate member may engage with said control means. Movement of said detection member may engage or disengage said further elongate member with said control means.

Said actuable member may be linked to said detection member by said shaft such that actuation of said actuable member may move said detection member between said open and closed position. The actuable member may comprise an extended position or configuration and a retracted position or configuration.

In some examples, in the extended configuration of said actuable member said detection member may be in the open position. In the retracted configuration of said actuable member said detection member may be in the closed position.

In some examples, the actuable member may comprise a further resilient member. The further resilient member may actuate or bias the actuable member into the extended position. The actuable member may be actuated or actuable into the retracted and/or extended position by movement of the detection member. For example, in the open or partially open position of the detection member, the actuable member may be in the retracted position.

In some examples, the coupling arrangement may comprise or define a cam and follower arrangement. The shaft may be adapted to provide a cam profile or surface. The shaft may comprise a central portion, which may incorporate the cam profile or surface on an outer surface of the central portion of the shaft. The cam surface may be arranged for engagement with the actuable member. For example, the actuable member may comprise a profiled portion, which may be arranged so as to engage with the cam surface of the shaft.

The coupling arrangement may be arranged to link or couple movement of the detection member and/or shaft to the actuable member. The coupling arrangement may be adapted to actuate the actuable member in the extended or retracted position, e.g. in response to movement of the detection member and/or shaft.

The apparatus may comprise an arrangement of one or more control member(s). Said control means may comprise the arrangement of one or more control member(s). When implemented as one ore more control valves, said one or more control member(s) may be actuable, e.g. hydraulically or pneumatically actuable.

At least one of the one or more control member(s) may be manually operable.

The apparatus may comprise connection means for linking or connecting the one or more control member(s) to one another and/or to the actuable member.

Said control member(s) may be linked by the connection means, which may transmit the signal between said control member(s).

For example, said one or more control members and/or control valves may be linked by a connecting lines, tubing, hose, conduit or the like, which may conduct a pressurised fluid. The apparatus may comprise a first control member. Said arrangement of one or more control member(s) may comprise the first control member which may be coupled to a signal source e.g. a hydraulic or pressurised fluid source. Said first control member may be linked to said actuable member. Said first control member may be adapted to actuate said actuable member into said extended or retracted position, i.e. said first control member may move said detection member into said open or closed position.

In some examples, the first control member may be actuable between a first position and a second position. In the first position, the first control member may be connected to the signal source, e.g. for transmission of the signal. In the second position, the first control member may be disconnected from the signal source. The first control member may be spring loaded and/or biased into the first position. The first control member may be actuated into the second position, e.g. by compressing a first spring or resilient member. The first control member may be coupled or linked to the actuable member for allowing transmission of the signal to the actuable member.

The apparatus may comprise a second and/or third control member. The second and/or third control member may be included in the arrangement of one or more control members.

In some examples, said first control member may transmit said signal to a second control member. Said second control member may be actuable between a further first and a further second position. In said further first position, said second control member may provide a signal transmission path to a third control member and in said further second position, said second control member may prevent said signal from being transmitted to said third control member. Said second control member may comprise an operator member which may be arranged to engage with said elongate member of said detection means.

In use, said further elongate member may engage with said operator member and actuate said second control member, which may be spring loaded, into either said further first or second position. This may be achieved, for example, by engaging said further elongate member with said operator member which may cause compression of said spring.

Said third control member may be coupled to tool moving means, such as a motor or winch motor. Said third control member may be actuable between a yet further first and a further second position. In said yet further first position of said third control member said tool moving means may be activated and in said yet further second position of said third member said tool moving means may be de-activated. Optionally, said third control member may be spring loaded and upon reception of said signal compression of said spring may de-activate said tool moving means.

Alternatively or additionally, the second control member may be coupled or linked to the tool moving means. The second control member may be actuable between a further first position and a further second position. In this example, in the further first position, the second control member may activate the tool moving means to move the tool in the passage. In the further second position, the control member may de-activate the tool moving means. The second control member may be biased or spring loaded into the further first position. For example, upon reception of the signal the second control member may be actuated into the further second position, e.g. by compression of a second spring or resilient member , thereby de-activating the tool moving means. The second control member may be coupled to the actuable member for allowing transmission of the signal from the actuable member to the second control member.

The actuable member may couple or link the first control member to the second control member.

Alternatively or additionally, in the closed position of the detection member, the actuable member may prevent transmission of the signal from the first control member to the second control member, e.g. in use. In the closed position of the detection member, the first control member may be in the first position in which the first control member may be connected to the signal source. In the closed position of the detection member, the second control may be in the further first position, in which the tool moving means may be activated.

Alternatively or additionally, in the open or partially open position of the detection member, the actuable member may allow transmission of the signal from the first control member to the second control member, e.g. in use. In the open or partially open position of the detection member, the first control member may be in the first position, in which the first control member may be connected to the signal source. In the open or partially open position of the detection member, the second control may be in the further second position, in which the tool moving means may be de-activated.

Optionally said first, second and/or third control members may be implemented as first, second and/or third control valves. In use, said first control valve may be coupled to a supply of pressurised (hydraulic or pneumatic) fluid which may be transmitted to either said actuable member for control of said detection member and/or to said second control valve. In use, said second control valve may either allow or prevent transmission of said pressurised fluid to said third control valve. In use, said pressurised (hydraulic) fluid may actuate said third control valve into said further second position, i.e. may cause de-activation of said moving means.

In use, said apparatus may comprise an open, a closed and an armed configuration.

In said open configuration said signal may be transmitted from said first control member to said actuable member. Said signal may actuate said actuable member into said extended position and said detection member into said open position. In said open configuration said third control member may be in said yet further first position in which said tool moving means may be activated. In said open configuration of said apparatus said tool may be deployed within said passage.

In said closed configuration said first control member may transmit said signal to said actuable member which may move said actuable member into said retracted position and said detection member into said closed position. Said movement of said detection member from said open to closed position may cause said further elongate member to engage with said operator member of said second control member. In said closed position said first control member is configured such that signal transmission to said second control member is prohibited. Said second control member may be in said further second position and may prevent said signal from being transmitted to said third control member.

In said armed configuration said signal may be transmitted from said first control member to said second control member, which may be maintained in said further second position. In said armed configuration said third control member may be maintained in said yet further first position and said tool moving means may be activated. In use, said tool may be moved within said passage by operating said tool moving means.

In use, when said tool reaches said predetermined position, it may engage with said detection member. In use, further movement of said tool may cause said detection member to move from said closed position to said open position and activate said apparatus. The movement of said detection member may actuate said second control member from said further second position into said first position by disengaging said further elongate member from said operator member of said second control member. Said signal may be transmitted to said third control member which may be actuated into said yet further second position and de-activate said tool moving means. For preventing inadvertent closure of said detection member, said second control member may be linked to said actuable member.

When said apparatus is activated, transmission of said signal from said second control member to said actuable member may actuate or maintain said detection means into said open position. A further control member may be coupled to said third control member. Said further control member may be arranged to maintain said third control member in said further second position, i.e. maintaining said tool moving means de-activated.

Alternatively or additionally, in use, the apparatus may comprise an active and an override configuration. The apparatus may be operated in the active configuration by maintaining or releasing the first control member in the first position. The apparatus may be operated in the override configuration by actuating, such as manually or automatically actuating, the first control member in the second position. For example, the first control member may be manually or automatically actuated in the second position by a control lever, control switch or the like.

In the active configuration, the first control member is connected to the signal source and the signal may be transmitted from the first control member to the actuable member, e.g. in use. The actuable member may either allow or prohibit transmission of the signal to the second control member, which may dependent on the position of the detection member. In the closed position of the detection member, the actuable member may prevent transmission of the signal from the first control member to the second control member and the tool moving means may be activated. In use, the tool may be moved within the passage.

In use, when tool reaches the pre-determined position, it may engage with the detection member. In use further movement of the tool may cause the detection member to move from the closed position to the open or partially open position, which may activate the apparatus. The cam surface on the shaft may interoperate or co-act with the actuable member, in use. The cam surface on the shaft may actuate the actuable member into the retracted position, in which the signal may be transmitted from the first control member to the second control member. In use, upon reception of the signal, the second control member may be actuated from the further first position to the further second position, thereby de-activating the tool moving means.

In use, the detection member may return to the closed when the tool has passed or partially passed the pre-determined position and/or is disengaged from the detection member. The actuable member may be maintained in the retracted position by transmitting the signal from the first control member to the actuable member, which may prevent inadvertent activation of the tool moving means, e.g. in use. The signal may maintain the actuable member in the retracted position, in which the actuable member may be disengaged from the shaft. By maintaining the actuable member in the retracted position, accidental or inadvertently reactivation of the tool moving means may be prevented. The deactivation of the moving means may prevent the tool from being further moved within the passage, thereby preventing damage to the tool and/or the apparatus.

In use, the tool moving means may be reactivated by actuating, such as manually or automatically actuating, the first control means into the override position. In the override configuration, the first control member may be disconnected from the signal source and no signal may be transmitted to the actuable member, e.g. in use. In use, the actuable member may return to the extended position, in which it may engage with the shaft. In use, the second control member may return or be actuated in the further first position, in which the tool moving means are activated. Activation of the tool moving means may allow movement of the tool within the passage and/or retrieval of the tool from the passage.

In use, the apparatus may return to the active configuration by allowing the first control member to return to the active position, e.g. by actuating or releasing the first control member into the first position.

Alternatively or additionally, the detection member may be manually actuatable from the open to the closed position, or vice versa. By manually actuating the detection member from the open to the closed position, or vice versa, retrieval of the tool may be allowed when the tool has engaged with the detection member or further movement of the tool is prevented by the detection member.

The shaft may comprise a portion, such as an end portion, which may at least partly project from an outer or external portion of the passage. The end portion of the shaft may be adapted for engagement, e.g. engagement external to the passage, with a further tool or the like. The end portion of the shaft may be rotatably arranged for rotational movement about or around a longitudinal axis thereof. In response to rotational movement of the further tool, the end portion of the shaft may rotate about or around the longitudinal axis thereof. The end portion of the shaft may comprise a tool engagement portion. The tool engagement portion may be adapted to complement or match a further tool engagement portion of the further tool. In this example, the tool engagement portion may comprise two flat surfaces, which may define a substantially rectangular cross-section. In other examples, the tool engagement portion may have a substantially hexagonal, squared, circular, trapezoidal, triangular, oval or the like cross- section.

The end portion of the shaft may be arranged and/or adapted to inter- engagingly couple with the central portion of the shaft.

The central portion of the shaft may comprise a first protrusion or recess. The end portion of the shaft may comprise a second protrusion or recess. The first and second protrusions may define an interengaging coupling arrangement between the central portion and the end portion of the shaft.

The first and second protrusions may be arranged so as to co-act or interoperate, in use.

In use, rotation or rotational movement of the end portion of the shaft may cause engagement of the first and second protrusions. Further rotational movement of the end portion of the shaft may cause rotational or pivotal movement of the central portion, in use.

In use, rotational movement of the shaft may move the detection member from the closed to the open or partially open position, or vice versa.

The end portion of the shaft may comprise a first slot or recess. The first slot may be arranged substantially perpendicular to the longitudinal axis of the end portion of the shaft.

A portion, such as an external portion, of the passage may comprise a second slot or recess.

In use, rotation of the end portion of the shaft may align the first slot with respect to the second slot of the passage. When the first and second slots are aligned a pin or bolt may be inserted in the first and second slots. Insertion of the pin in the first and second slots may prevent movement, such as rotational, of the central portion and/or end portion of the shaft with respect to the passage, thereby preventing movement of the detection member.

Prior to alignment of the first and second slots, the end portion of the shaft may actuate the detection member in the open or closed position, in use. When the first and second slots are aligned, the detection member may be in the open or closed position.

In use, insertion of the pin may retain the detection member in the open or closed position.

Rotation of the end portion of the shaft may actuate, such as manually actuate, the detection member from the closed position to the open position, or vice versa. By manually actuating the detection member in the open position, retrieval of the tool may be allowed.

In the open position of the detection member, the tool moving means may be activateable or activated by actuating the first control member into the override position.

Optionally, said tool may be a downhole tool such as a drilling tool or logging tool. Said tool may be deployed on a wireline.

Optionally, said passage may be a casing, tubular or liner deployed with in a bore well.

According to a second aspect of the present invention there is provided a method of controlling the position of a tool within a passage, said method comprising the steps of:

detecting said position of said tool in said passage at a predetermined location; sending a signal to control means when said tool reaches said predetermined position; and

stopping further movement of said tool.

According to a third aspect of the present invention there is provided a lubricator section including an apparatus for controlling the position of a tool within said lubricator section according to the first and/or second aspect of the present invention.

It should be understood that the features defined above in accordance with any aspect of the present invention or below in relation to any specific embodiment of the invention may be utilised, either alone or in combination with any other defined feature, in any other aspect or embodiment of the invention.

Brief Description of the Drawings

These and other aspects of the present invention will now be described with reference to the accompanying drawings, in which:

Figure 1 is a longitudinal section of an apparatus for controlling the position of a tool in a passage in accordance with a first embodiment of the present invention with a flapper valve, adapted with a groove to permit passage of a wireline, in an open position;

Figure 2 is a view similar to Figure 1 with a tool shown in the passage;

Figure 3 is a view similar to Figure 2 with the passage shown closed by the flapper valve;

Figure 4 shows a similar representation of the passage comprising the tool in a position just before contact with the flapper valve; Figure 5 shows a similar representation of Figure 4 with the tool just after engagement with the flapper valve;

Figure 6 shows a similar representation of the passage comprising the tool with the flapper valve in the open position;

Figure 7 shows a similar representation of the passage with the tool pulled through the apparatus with the flapper valve returned to the closed position;

Figure 8 shows an enlarged representation, taken in the direction of arrow A, of a coupling arrangement of the apparatus shown in Figure 4;

Figure 9 is a view similar to Figure 8, showing the position of the coupling arrangement with the tool in the position of Figure 5;

Figure 10 shows a representation of the coupling arrangement of the apparatus of Figure 1 with the flapper valve open;

Figure 1 1 shows a schematic diagram of an arrangement of one or more control member(s) of the apparatus of Figure 1 in the open configuration;

Figure 12 shows a schematic diagram of an arrangement of one or more control member(s) of the apparatus of Figure 3 in the closed configuration;

Figure 13 shows a schematic diagram of an arrangement of one or more control member(s) of the apparatus of Figures 3 and 4 in an armed configuration;

Figure 14 shows a schematic diagram of an arrangement of one or more control member(s) of the apparatus of Figure 6 in an activated configuration;

Figure 15 is an external isometric view of an apparatus for controlling the position of a tool in a passage in accordance with a second embodiment of the present invention;

Figure 16 is a sectional isometric view of the apparatus of Figure 15 with two fingers extending in the passage, in a closed position;

Figure 17 is a longitudinal sectional view of the apparatus of Figure 16 showing the coupling arrangement between the controller and the two fingers, in the closed postion;

Figure 18 is an detailed view of the apparatus of Figure 17;

Figure 19 is a longitudinal sectional view with a tool in the passage, deflecting the fingers downwards;

Figure 20 is a longitudinal sectional view with the tool engaging with the fingers;

Figure 21 is a similar view to Figure 20 with the tool just after engagement with the fingers; Figure 22 a schematic diagram of an arrangement of one or more control member(s) of the apparatus of Figure 15 in the closed and active configuration;

Figure 23 shows a schematic diagram of an arrangement of one or more control member(s) of the apparatus of Figure 15 in the open or partially open and active configuration;

Figure 24 shows a schematic diagram of an arrangement of one or more control member(s) of the apparatus of Figure 15 in the closed and active configuration after the tool has engaged the fingers;

Figure 25 shows a schematic diagram of an arrangement of one or more control member(s) of the apparatus of Figure 15 in the open or partially open and override configuration;

Figure 26 shows a schematic diagram of an arrangement of one or more control member(s) of the apparatus of Figure 15 in the closed and override configuration;

Figure 27 shows an isometric view of an end portion of a shaft of the apparatus of Figure 16;

Figure 28 shows an isometric view of a central portion of a shaft, comprising the fingers, of the apparatus of Figure 16;

Figure 29 shows an isometric view of the end portion of the shaft coupled to the central portion of the shaft of Figure 27 with fingers in the closed position;

Figure 30 shows an isometric view of the end portion of the shaft coupled to the central portion of the shaft of Figure 27 with fingers in a downwards position;

Figure 31 shows an isometric view of the end portion of the shaft coupled to the central portion of the shaft of Figure 27 with fingers in a upwards position;

Figure 32 shows a similar view to Figure 30 a first protrusion of the end portion of the shaft being engaged with a second protrusion of the central portion of the shaft;

Figure 33 shows a similar view to Figure 31 a first protrusion of the end portion of the shaft being engaged with a second protrusion of the central portion of the shaft;

Figure 34 shows a cross-sectional view of the passage of the apparatus of Figure 16 at the predetermined position with the fingers in the closed position, whereby a first slot of the shaft and a second slot of the passage in misalignment; and

Figure 35 is a similar view to Figure 34 with the fingers in the open position, whereby the first slot of the shaft and the second slot of the passage in alignment and a pin inserted in the first and second slots. Detailed Description of the Drawings

Reference is first made to Figures 1 to 7 in which there is shown a first embodiment of an apparatus, generally indicated by reference numeral 10, for controlling the position of a downhole tool or toolstring 12 in a bore 14 of a lubricator section 15 in accordance with an embodiment of the present invention. The apparatus 10 comprises a position detector 16 for detecting the position of the tool 12 in the bore 14, the detector 16 being coupled to a controller 18, as will be later described in detail, for moving or detecting the tool 12 within the bore 14, whereby when the tool 12 reaches a predetermined position 20, the detector 16 sends a signal to the controller 18 to stop further movement of the tool 12.

As can be seen in Figures 1 to 7 in this embodiment, the detector 16 is provided by a flapper valve 26 within and/or on the bore 14. While this example shows a flapper valve as the detector, it will be appreciated that in further examples, the detector may be a elongate member or finger or the like. In this embodiment, the bore 14 is defined by the lubricator section housing 22 which has standard wireline lubricator section connections at each end (not shown) to enable the housing 22 to be incorporated within a stack of lubricators (not shown).

The flapper valve 26 includes a flapper valve plate 28 mounted to the lubricator section housing 22 for pivotal movement between an open position, shown in Figures 1 , and a closed position, shown in Figure 5. The flapper valve plate 28 has a V-shaped groove 27, adapted to permit passage of a wire or wireline 17, as shown in Figures 1 to 7. The flapper valve 26 may not contain any sealing components, such as face seals or seats and thus, may be free from fluids.

The flapper valve plate 28 is mounted on a shaft 30 which passes through housing wall 22 (a). As seen in Figure 5, in the closed position the flapper valve plate 28 occludes the bore 14 of the housing 22 at the predetermined position 20. The shaft 30 engages with the bore 14 of the housing 22 where it is sealed with chevron type stem packing seals (not shown) to the housing 22. The housing 22 may be incorporated within a stack of lubricators in a position which will allow sufficient time to stop the movement of the tool 12, for example, above blow out preventers of the wireline.

Referring now to Figures 8 to 10, detector 16 further comprises a coupling arrangement 34 for linking the movement of the flapper valve plate 28 to the controller 18. Here, the coupling arrangement 34 comprises an actuable member 36, such as a piston or double acting piston, and a cam lug 38, provided on the outer or external portion of the housing 22. In other embodiments, the actuable member may be a valve, such as a poppet valve or the like. The cam lug 38 is mounted on the shaft 30. In this embodiment, the ends of the shaft 30 are modified to include two flat surfaces 40 which engage with a sliding connector 42, which is attached to the end of the double acting piston 36. The sliding connector 42 is arranged to slide with respect to the two flat surfaces 40 of the shaft 30.

The cam lug 38 is linked to the movement of the flapper valve plate 28 by the shaft 30 such that in the closed position of the flapper valve 26 the cam lug 38 engages with the controller 18. As seen in Figures 1 to 10, movement of the flapper valve 26 engages the cam lug 38 and the controller 18.

The piston 36 is linked to the flapper valve plate 28 by the shaft 30 such that actuation of the piston 36 moves the flapper valve 26 between the open and closed position. When the piston 36 is moved to the extended configuration 44 (see also Figures 10 and 1 1 ) this rotates the sliding connector 42 and shaft 30 and moves the flapper valve plate 28 into the open position. Alternatively, when the piston 36 is moved to the retracted configuration 46 (Figures 8 and 12) the sliding connector 42 and shaft 30 are rotated to move the flapper valve plate 28 into the closed position.

Referring now to Figures 1 1 to 14, the controller 18 comprises an arrangement of one or more control elements 48. The control elements 48 are linked by hydraulic or pneumatic lines 50 which transmit the signal between the control elements 48. It will be appreciated that in other embodiment, the connecting lines may one or more tubulars or conduits or the like.

In this embodiment, the one or more control valves are linked by connecting lines 50, i.e. ancillary components and connection hoses, which conduct a pressurised fluid (hydraulic fluid).

The arrangement of one or more control elements 48 comprises a first control valve 52 which is coupled to a source or supply 54 of hydraulic fluid. The first control valve 52 is an arming valve, which is located at the winch motor 78. The first control valve 52 is a six-way, three-position, lever actuated control valve comprising two inlet or supply ports 56 (a) and (b) and one vent or return port 58. The lever of the first control valve 52 can be manually operated. The first control valve 52 has three outlets 60 (a), (b), and (c), two of which (60(b) and (c)) are connected to an extend 62 or retract side 64 of the piston. The third outlet 60 (a) is connected to an inlet 66 of a second control valve 68, as can be seen in Figures 1 1 to 14. The connection between the first control valve 52 and second control valve 68 is established using flexible hoses of sufficient length to reach from the lubricator (not shown) to the winch motor 78 which may be located at a different position.

Still referring to Figures 1 1 to 14, the first control valve 52 is coupled to a supply of hydraulic fluid 54 which is transmitted to either the piston 36 for control of the flapper valve plate 28 or to the second control valve 68. The first control valve 52 actuates the piston 36 into either the extended 44 or retracted position 46, i.e. the first control valve 52 actuates the flapper valve 26 into either the open or closed position.

In this embodiment, the second valve 68 is located on the outside of the housing 22. The second control valve 68 is a three-way, two-position, spring loaded valve which may be operated by the cam lug 38. The second control 68 valve has an inlet port 66 which is connected to the first control valve 52. It also has an outlet port 70 which is connected to a third control valve 72.

The second control valve 68 is actuable between a first and a second configuration. In the first configuration, the second control valve 68 provides a transmission path of the hydraulic fluid to the third control valve 72 (Figure 1 1 ). In the second configuration, the second control valve 68 prevents the hydraulic fluid from being transmitted to the third control valve 72. The second control valve 68 comprises an operator member 74, which engages with the cam lug 38, as shown in Figures 12 and 13.

In use, the cam lug 38 engages with the operator member 74 and actuates the second control valve 68, which is spring loaded, into either the first or second configuration. This is achieved by engaging the cam lug 38 with the operator member 74 which causes compression of the spring 76.

The third control valve 72 has an output 86 (b) coupled to tool moving means, such as a motor or winch motor 78. The third control valve 72 is actuable between a further first and a further second position. In the further first position of the third control valve 72 the winch motor 78 is activated and in the further second position of the third control valve 72 the winch motor 78 is de-activated. The third control valve 72 is spring loaded and upon reception of the hydraulic fluid compression of the spring 80 de- activates the winch motor 78.

In this embodiment, the third control valve 72 is a four-way, two-position pilot actuated return valve. A supply of hydraulic fluid 82 is connected to an inlet port 84 of the third control valve 72. The third control valve 72 also comprises two outlets 86 (a) and (b) which discharge the pressurised fluid to the hydraulic winch motor 78 or allow it to vent or return to a tank 79. The actuator 88 of this valve is fed from the outlet 70 of the second control valve 68.

In use, the apparatus 10 can be configured one of three ways: an open 90, a closed 92 and an armed 94 configuration.

Referring to Figures 1 , 10, and 1 1 in which there is shown the apparatus 10 in the open configuration. In the open configuration 90 the hydraulic fluid is transmitted from the first control valve 52 to the piston 36. The fluid actuates the piston 36 into the extended position 44 and the flapper valve 26 into the open position. This is achieved by setting the first control valve 52 to the open configuration 90 using a lever. Fluid enters at the supply port 54 and is transmitted via the hose to the extend side 62 of the piston. The retract side 64 of the piston 36 is configured to vent. As seen in Figure 11 , there is no hydraulic fluid being delivered to the second control valve 74 and no pressure in a pilot line 96 which connects the second 68 and third 72 control valves. The third control valve 72 is maintained in the further first position by the spring 80 and hydraulic fluid is transmitted to the winch motor 78 from the supply 82, i.e. it is activated. In this configuration an operator has the full control over the winch. The wireline tool or toolstring 12 is assembled and deployed into the lubricator, as seen in Figure 2.

Once the toolstring 12 has passed the apparatus 10, the operator sets the first control valve 52 to the closed configuration 92. In the closed configuration 92 the first control valve 52 transmits the fluid to the piston 36 which moves the piston 36 into the retracted position 46 and the flapper valve plate 28 into the closed position. This is achieved by supplying fluid to the retract side 64 of the piston 36 and the extended side 62 is allowed to vent. The piston 36 fully retracts and the flapper valve 26 moves into the closed position. The sliding connector 42 and the piston 36 are arranged externally to the housing 22. Thus, from the position of the sliding connector 42 and the piston 36, as seen in Figure 8, it is possible to monitor the position of the flapper valve plate 28. In the closed position of the flapper valve 26, the cam lug 38 engages with the operator member 74 of the second control valve, as seen in Figure 8.

Referring to Figure 12, the second control valve 68 is in the second position and prevents the hydraulic fluid from being transmitted to the third control valve 72. The third control valve 72 is maintained in the further first position by the spring 80 and hydraulic fluid is transmitted to the winch motor 78 from the supply 82, i.e. it is activated. In this configuration the operator continues to have full control over a winch which is operable by the winch motor 78. Referring now to Figure 13, in the armed configuration 94 the hydraulic fluid is transmitted from the first control valve 52 to the second valve 68 by routing the fluid to the inlet port 66 of the second control valve 68. As the second control valve is in the second position, the fluid is prevented from onward transmission to the third control valve 72. The cam lug 38 presses onto the operator member 74 of the second control valve 68 and maintains it in the second position. The toolstring 12 can be moved, i.e. lowered or retracted, within the lubricator with the wire 17 passing through the V- shaped groove 27 of the flapper valve plate 28. Under normal operations the toolstring 12 does not interact with the apparatus 10.

Upon completion of the wireline operations, the toolstring 12 may be retracted to the surface. As this may take a considerable amount of time, the retraction generally occurs at high speeds. Once the toolstring 12 reaches the lubricator, the retraction speed is usually slowed. The position of the toolstring 12 may be monitored. However, the position of the toolstring 12 may not be accurate.

Referring to Figure 4, there is shown the situation where the toolstring 12 has just reached the flapper valve plate 28. Further movement of the toolstring 12 causes the flapper valve 26 to move from the closed position to the open position. This movement actuates the second control valve 68 into the first position caused by disengagement of the cam lug 38 from the operator member 74 of the second control valve 68, as shown in Figures 5, 9 and 14. Fluid pressure at the inlet 66 of the second control valve 68 can be delivered to the outlet 70 and onwards to the third control valve 72. The third control valve 72 is actuated into the further second position and deactivates the winch motor 78 by routing the supply 82 pressure from the winch motor 78 into the vent 79. The retraction of the toolstring 12 is stopped.

To prevent the flapper valve plate 28, from accidentally closing and fluid from returning to the winch motor 78, the second control valve 68 is linked to the piston 36, as seen in Figures 1 1 to 14. This is achieved by an additional line 98, which connects the pilot line 96 to the piston 36 and extends via a shuttle valve 100. When the apparatus 10 is activated (Figure 14), pressurised fluid flowing along the pilot line 96 is simultaneously fed into the extend side 62 of the piston and the flapper valve 26 is maintained in the open position. An additional check valve 102 is arranged into the pilot line 96 to prevent backflow of pressure and maintaining pressure on the third control valve 72, i.e. maintaining the winch motor 78 de-activated. The third control valve 72 is returned to the further first position by venting the pilot line 56 pressure via a valve such as a needle valve 104. Figures 15 to 35 show a second embodiment of an apparatus 10 for controlling the position of a tool in a passage. The arrangement of Figures of 15 to 35 is similar to that of Figures 1 to 14, and as such, and to facilitate understanding, like features share like reference numerals, incremented by 200.

Referring to Figures 15 to 22 in which there is shown an apparatus 10 for controlling the position of a downhole tool or tool string 212 in a bore 214 of a lubricator section 215 in accordance with an embodiment of the present invention. The apparatus 10 comprises a position detector 216 being coupled to a controller 218 (best seen in Figure 17 and 18), as will be later described in detail, for detecting the tool 212 in the bore 214, whereby when the tool 212 reaches a predetermined position 220, the detector 216 sends a signal to the controller 218 to stop further movement of the tool 212.

As can be seen in Figures 16 to 21 , in this embodiment the detector 216 is provided by two fingers 106 within and/or on the bore 214 at the predetermined position 220 within the bore 214. It will be appreciated that in further examples, a single or more than two fingers may be used and/or that the detector may be provided by a valve, such as a flapper valve or the like.. The fingers 106 are mounted to the lubricator section housing 222 for pivotal movement between an open or partially open position, shown in Figures 19 and 20, and a closed position, shown in Figures 16 to 18 and 21 . In this embodiment, the detector 216 has two fingers 106. The fingers 106 are mounted on a shaft 107 which has an override shaft 107a which passes through housing wall 222 (a). As can be seen in Figure 16, the shaft 107 projects to an outer or external portion of the housing 222. The fingers 106 are coupled to the shaft 107 so as to partially extend into or across the bore 214 in the closed position.

The housing 222 can be adapted to comprise a recess 105, in which the shaft

107 is mounted.

The fingers 106 are spaced apart on the shaft 107 to permit passage of a wire or wireline 217. As shown in Figures 16 to 18, the fingers 106 extend substantially horizontally into the bore 214 in the closed position. In this embodiment, the fingers are arranged on or coupled to a central portion 107 (a) of the shaft 107. Pivotal movement of the fingers 106 causes the shaft 107 to move or rotate about a longitudinal axis 108 of the shaft 107.

The fingers 106 are maintained or biased in the closed position by one or more resilient member(s), such as one or more springs or torsion springs 1 10 (Figures 29 to 33), arranged on the shaft 107 and has a tang 1 10a and which fits within a pocket (not shown) to provide a reaction to the spring force of the housing 222 (not shown).

In this embodiment, the apparatus 10 comprise a coupling arrangement 1 12, best seen in Figure 17, which links the detector 216 to the controller 218, shown in Figures 17 to 21 and 29 to 35. The coupling arrangement 1 12 comprises an actuable member 1 13, which is in this example, a poppet valve 1 14. It will be appreciated that in other examples, the actuable member may be a piston or double-action or the like. The poppet valve 1 14 has an extended position, shown in Figures 17 to 19, and a retracted position, shown in Figures 20 and 21 . The poppet valve includes a further resilient member, such as a further spring 1 16, which actuates or biases the poppet valve 1 14 into the extended position. The poppet valve 1 14 can be actuated into the retracted position by movement of the fingers 106, e.g. when the tool 212 engages the fingers 106, so that in the open or partially open position of the detector 216, the poppet valve 1 14 is in the retracted position (Figure 20).

In this embodiment, the coupling arrangement 1 12 is provided by a cam and follower arrangement. It will be appreciated that other arrangements, for example that described in relation to the first embodiment can link the detector to the controller. The shaft 130 is adapted to provide a cam profile or surface 1 18, as shown in Figures 17 to 21 and 31 to 35, which is incorporated on an outer surface of the central portion 107 (a) of the of the shaft 107. The poppet valve 1 14 comprises a profiled portion 120, which is arranged so as to engage with the cam surface 1 18 of the shaft 107. The coupling arrangement 1 12 is arranged to link or couple movement of the fingers and/or shaft 130 to the poppet valve 1 14, which actuates the poppet valve 114 by compression of the further spring in the retracted position.

Referring to Figures 22 to 26, the controller 218 comprises an arrangement of one or more control elements 122. The one or more control elements 122 can be implemented as one or more control valves 123, which may be pneumatically or hydraulically actuable. The one or more valves 123 are linked by connecting fluid lines 250 (a) and (b), such as ancillary components and/or connection hoses, which conduct a pressurised fluid, such as a hydraulic fluid

The arrangement of one or more control elements 122 comprises a first control valve 124. The first control valve is connectable to signal source, such as a supply of hydraulic or pneumatic fluid 126, which can be transmitted to the poppet valve 1 14 by line 250 (a). In this embodiment, the first control valve 124 comprises an inlet or supply port 127 and a vent or return port 128. The first control valve 124 has an outlet 129, which can be connected to an inlet 130 of the poppet valve 1 14, best seen in Figure 22. The first control valve 124 is actuable between a first position, in which the first control valve 124, i.e. the inlet 127 of the first control valve 124, is connected to the fluid supply 126 and a second position, in which the first control valve 124 is connected to vent or return to a tank 131 . The first valve can be lever actuated or manually lever actuated between the first and second position. The first control valve 124 is a spring loaded control valve, whereby a first spring 132 biases the first control valve 124 into the first position, as shown in Figures 22 to 24. The first control valve 124 can be actuated into the second position by actuating a lever or switch (not shown), which cause compression of the first spring 132.

The control arrangement 122 comprises a second control valve 134. The second control valve is coupled to tool moving means, such as a motor or winch motor 136. The second control valve 134 is actuable between a further first position, in which the motor or winch 136 is activated and a further second position, in which the winch motor 136 is de-activated. The second control valve 134 is spring loaded and upon reception of the pneumatic or hydraulic fluid compression of a second spring 138 deactivates the winch motor 136. In this embodiment, the second control valve 134 comprises an inlet or port 140 to which a further supply of pressurised (hydraulic or pneumatic) fluid 142 is connected. The second control valve also comprises two outlets 144 ,145 which discharge the fluid to the winch motor 136 or allow it vent or return to a tank 146.

The second control valve 134 is coupled to the poppet valve 1 14 by line 250 (b) for allowing transmission of the fluid from an outlet 150 of the poppet valve 1 14 to the second control valve 134. Here, the poppet valve 1 14 couples the first control valve 124 to the second control valve 134. An actuator 148 of the second control valve 134 is fed from an outlet 150 of the poppet valve 1 14.

Referring to Figure 19, there is shown the fingers 106 in a partially open and downward position. The downward position of the fingers 106 maintains the poppet valve 1 14 in the extended position with spring 1 16 uncompressed, thereby preventing transmission of fluid from the first control valve 124 to the second control valve 134, which can allow for deployment of the tool 212.

As can be seen in Figure18 and 22, in the closed position of the fingers 106, the poppet valve 1 14 prevents transmission of the fluid from the first control valve 124 to the second control valve 134, in use. The poppet valve 1 14 has two surfaces 1 15, which abut two further surfaces 1 17 (a) of an enclosure or housing of the poppet valve, thereby preventing transmission of the fluid, as shown in Figure 22.

In the closed position of the finger 106, the first control valve 134 is in the first position, in which the first control valve 124 is connected to the fluid supply 126, and the second valve 134 is in the further first position, in which the winch motor 136 is activated. In this configuration, an operator has full control over the winch, and the tool 212 can be moved in the bore 214.

Referring to Figure 20 and 23, there is shown the fingers 106 in a partially open position. In the open position or partially open position of the fingers, the poppet valve 1 14 allows transmission of the fluid from the first control valve 124 to the second control valve 134, in use. In the open position of the fingers, the first control valve 124 is in the first position, in which the first control valve 124 is connected to the fluid supply 126, and the second control valve 134 is in the further second position, in which the winch motor is de-activated.

In use, the apparatus 10 comprises an active 152 and an override 154 configuration (Figures 22 to 26). The apparatus 10 can be operated in the active 152 configuration by maintaining or actuating the first control valve 124 in the first position. The apparatus 10 can be operated in the override 154 configuration by actuating the first control valve 124 in the second position.

In the active configuration 152, the first control valve is connected to the fluid supply 126 and the fluid can be transmitted from the first control valve 124 to the poppet valve 1 14 (Figures 22 to 24). The poppet valve 1 14 either allows or prohibits transmission of the fluid to the second control valve 134, which depends on the position of the fingers 106.

In use, when tool 212 reaches the pre-determined position 220, it engages with the fingers 106. In use further movement of the tool 212 causes the fingers to move from the closed position to the open position, as shown in Figure 19, which activates the apparatus 10. The cam surface 1 18 on the shaft 107 engages with the profiled portion 120 of the poppet valve 1 14, in use. The cam surface 1 18 on the shaft 107 actuates the poppet valve 1 14 into the retracted position, as shown in Figures 19 and 23, in which the fluid enters the inlet 130 of the poppet valve 1 14 and is transmitted to the outlet 150 of the poppet valve. The fluid is transmitted from the outlet 150 of the poppet valve to the actuator 148 of the second control valve 134. Upon reception of the fluid, the second control valve 134 is actuated from the further first position to the further second position, thereby de-activating the winch motor 136. Supply pressure at the inlet 142 of the second control valve 134 is routed from the winch motor 136 into vent 146. The retraction of the tool 212 is stopped.

In use, the fingers 106 may return to the closed when the tool has passed the pre-determined position, as shown in Figure 21 and 24. The poppet valve 1 14 is maintained in the retracted position by the pressurised fluid transmitted from the first control valve 124 to the inlet 130 of the poppet valve 1 14. The fluid pressure maintains the poppet valve 1 14 in the retracted position, in which the profiled portion 130 is disengaged from the shaft 107, when the fingers 106 return to the closed position, as shown in Figure 21 and 24. By maintaining the poppet valve 1 14 in the retracted position, accidental or inadvertently reactivation of the winch motor 136 can be prevented. The deactivation of the winch motor 136 prevents the tool 212 from being further moved within the bore 214, thereby preventing damage to the tool 212 and/or the apparatus 10.

In use, the winch motor 136 can be re-activated by actuating the first control valve 124 into the override position, which is shown in Figures 25 and 26. In Figures 20 and 25, the tool 212 has partially passed the fingers. For retrieval of the tool, an operator may activate the winch motor 136 to allow complete passage of the tool 212 by actuating the first control valve 124 into the override position 154. In the override configuration, the first control valve 124 is disconnected from the signal source 126 and no fluid is be transmitted to the poppet valve 1 14. The poppet valve 1 14 can subsequently return to the extended position, in which it engages with the shaft 107, as shown in Figure 26. In the override position of the first control valve 124, the second control valve 134 can return to the further first position, thereby activating the winch motor 136. Activation of the winch motor allows movement of the tool 212 within the bore and/or retrieval of the tool 212 from the bore 214 or lubricator. Vent 128 of the first control valve 124 is routed to tank 131 , allowing line 250 (a) to be vented (Figure 22).

In use, the apparatus 10 returns to the active 152 configuration by actuating the first control valve 124 into the first position. In this embodiment, the first control valve 124 is actuated into the first position by releasing the compression of spring 132, for example by releasing a lever or switch.

Alternatively or additionally, the fingers 106 can be manually actuated from the open to the closed position, or vice versa. Although described in relation to the second embodiment, it will be appreciated that flapper valve and/or apparatus of the first embodiment may also be manually actuated from the open to the closed position, or vice versa, as will be described in the following. By manually actuating the fingers from the open to the closed position, or vice versa, retrieval of the tool 212 is possible, for example when the tool 212 has engaged with the detection member or further movement of the tool 212 is prevented by the fingers 106.

The shaft 107 comprises an end portion 107 (b), which at least partly projects from an outer or external portion of the housing wall 222(a), as shown in Figure 15. Referring to Figure 27, there is shown the end portion 107 (b) of the shaft 107. The end portion 107 (b) of the shaft 107 is adapted for engagement with a further tool (not shown). The end portion 107 (b) of the shaft is rotatably arranged in the housing 222. In response to rotational movement of the further tool, the end portion of the shaft 107 (b) rotates about a longitudinal axis 108 (a) thereof. As can be seen in Figure 27, the end portion 107 (b) of the shaft comprises a tool engagement portion 156. The tool engagement portion 156 is adapted to match a further tool engagement portion of the further tool. In this embodiment, the tool engagement portion 156 has to substantially flat surface, which provide a substantially rectangular cross-section of the tool engagement portion 156. The end portion 107 (b) of the shaft has a first protrusion 158, for example at an end opposite to the tool engagement portion.

The end portion 107 (b) of the shaft is arranged and/or adapted to inter- engagingly couple with the central portion 107 (a) of the shaft 107, in use.

Referring to Figure 28, the central portion 107 (a) of the shaft comprise a second protrusion 160. The first 158 and second 160 protrusions are arranged to interoperated with one another, in use, thereby defining an inter-engaging coupling arrangement between the central portion 107 (a) and the end portion 107 (b) of the shaft (Figures 29 to 35).

In use, rotation of the end portion 107 (b) of the shaft causes engagement of the first 158 and second 160 protrusions, as shown in Figures 31 and 35. Further rotational movement of the end portion 107 (b) of the shaft can cause rotational movement of the central portion (203(a), providing movement of the fingers 106 from the closed to the open position, or vice versa, in use

Referring to Figures 29 to 31 , the end portion of the shaft 107 (b) comprises a first slot 162, which is arranged substantially orthogonal to the longitudinal axis 108 of the shaft. The housing wall 122 (a) comprises a second slot 164, as shown in Figures 34 and 35.

In use, rotation of the end portion 107 (b) of the shaft (107) can align the first slot 162 with respect to the second slot 164 of the housing wall 222 (a) to allow insertion of a pin or bolt 166 into the first 162 and second 164 slots, as shown in Figure 35. Insertion of the pin 166 in the first 162 and second 164 slots prevents movement of the central 107 (a) and end 107 (b) portions of the shaft with respect to housing 222, thereby preventing movement of the fingers 106.

Figure 34 shows the first 162 and second slots 164 prior to alignment, and the fingers are in the closed position. By rotating the end portion 107 (b) of the shaft the fingers 106 can be actuated from the closed to the open position. In Figure 35, the fingers are in the open position and the first 162 and second 164 slots are aligned. In use, insertion of the pin 166 retains the fingers in the open position, thereby allowing retrieval of the tool 212 from the bore 214. In the open position of the fingers, the winch motor 136 be activated by actuating the first control valve 124 into the override position 154.

The word "fluid" or "pressure" have been used throughout the description. It will be apparent to one skilled in the art that either of compressed air or hydraulic control fluid may be used to actuate the control valves. Alternatively, the control valves may be electrically operable.

The embodiment described hereinbefore utilises a positive pressure within the pilot line to activate the third control valve. It will be apparent to those skilled in the art that valve can be actuated, for example, by an absence of pressure. Such an arrangement may be considered fail safe and is consistent with other Emergency Shut Down System which may be present on, for example, an oil rig.

The embodiment described hereinbefore utilises a mechanical detection member. It will be apparent to those skilled in the art that other detection mechanisms such as mechanical, magnetic or optic switches may be utilised and such switches may be actuated via electric cables.

In an alternative embodiment, the detector 16 comprises one or more magnetic switches adapted to sense the presence a ferritic or ferromagnetic object or tool 12 within the housing 22. The one or more switches can be arranged radially around the bore 14 of the housing 22. When the tool 12 is retracted to the surface, the one or more switches can detect its proximity to the housing 22 and trigger the deactivation of the winch motor 78.

The second embodiment reduces the likelihood that the device may not be armed; the device is always in the active or available position and although this could be overridden to do so requires considerable effort in that an operator would need to climb up to the device and insert a pin into a hole or equivalent and this is impractical and inconvenient. The provision of the separate override shaft ensures that the size of the spring can be greatly reduced, which makes the design much more practical, operational and economic. The fact that the poppet is latched into position once activated ensures that the device works with very short tools and this eliminates what is known as "short cycling". Another advantage of second embodiment is that the internal centralising torsion spring enables the design to be much more efficient because the spring does not need to rotate the pressure energised seals.

In yet another embodiment, the detector 16 comprises an arrangement of optical sensors adapted to emit and detect light. The optical sensors can be arranged radially around the bore 14 of the housing 22. The sensors can be adapted to emit and/or detect light which is radiated across the bore. When the tool 12 reaches the housing 22, the tool may disrupt or block the detection of light and trigger the deactivation of the winch motor 78.

It should be understood that the embodiments described herein are merely exemplary and that various modifications may be made thereto without departing from the scope of the invention.

For example, the detector 1 16 may inlcude a single finger 106. In other examples, the detector 116 may have more than two fingers 106, such as a plurality of fingers 106.

The actuable member 1 13 may be a valve, such a poppet valve, piston or double action piston.

For example, the first control vave 124 may be actuated into the first position by a switch or control switch.

In other examples, the tool engagement portion may have a substantially hexagonal, squared, circular, trapezoidal, triangular, oval or the like cross-section.

In other examples, pin 166 may retain the fingers 106 in the closed position.