NO20170293A1

NO20170293A1 - Autonomous plug tool

Info

Publication number: NO20170293A1
Application number: NO20170293A
Authority: NO
Inventors: Andreas Fliss
Original assignee: Archer Oiltools As
Priority date: 2017-02-28
Filing date: 2017-02-28
Publication date: 2018-08-29
Also published as: NO343273B1

Abstract

A petroleum well- (2) autonomous plug robot (1) comprising - a command and control unit (11); - one or more auxiliary tool unit (13); - a packer unit (15) arranged for setting in a liner (4) or casing (3); - an energy unit (17) for providing energy at least for setting said packer module (15).A petroleum well- (2) autonomous plug robot (1) comprising - a command and control unit (11); - one or more auxiliary tool units (13); - a packer unit (15) arranged for setting in a liner (4) or casing (3); - an energy unit (17) for providing energy at least for setting said packer module (15).

Description

Field of the invention

The present invention is a petroleum well autonomous plug robot. More specifically, the invention is a petroleum well autonomous plug robot having a command and control unit, a packer module arranged for setting in the well, and an energy module for providing energy at least for setting the packer module in the well.

Background art

Background art plugs are drill pipe conveyed plugs set by mechanical or hydraulic means or a combination thereof. Many providers have such plugs as part of their regular service, such as Archer Oiltools' LOCK (TM) plug series. Numerous such drill pipe string conveyed plugs have been set with success and have a long and proven track record. However, there may be situations and operations wherein one would need further developed plugs.

Background art plugs require, when being set on drillpipe (DP) some sort of manipulation of the drillpipe, eg. rotation (like Archer LOCK plugs) or straight axial down/up force, or a combination of both.

The present invention's plug robot (1) is, for the setting operation, independent of any of the “classic” oil well conveyance methods – drillpipe, coiled tubing, wireline/slickline meaning it is actually compatible with all of the classic conveyance methods and can be run independently by gravity drop or pump-down. If run on drillpipe string no rotation or straight down/pull force is required for the target positioning and setting. The background art drill pipe manipulation has many challenges especially in deviated and deep wells due to increasing drag and torque forces to be overcome along the drill pipe. There are many cases wherein a plug cannot be set or is being damaged due to either not being able to transmit the axial up/down force or torque down or applying on the contrary excessive torque and force. The drill pipe manipulation may in some instances pose a risk to the operation as described above and also requires time, particularly again, in deviated and deep wells. The present invention's plug robot (1) is an autonomous plug tool that will save significant rig time in gravity-drop or pump down mode, as no drill pipe is required to be run-in-hole except for possible conveyance to a first release position in the well, typically in a liner hanger or other restriction. Typically it takes between 1-2 hours per 1,000m of drill pipe to be run-in-hole or pull-out-of-hole, so any casing or liner transport length for the plug conveyed on a drill pipe string is valuable. An advantage of the pressure testing of the set plug robot (1) pressure integrity is that it the pressure can be induced from surface without having drillpipe partly or all the way down to the plug in the hole. Another advantage of the invention is that the entire plug setting operation has a smaller surface footprint eg. less equipment required to be operated, less people required on board, less logistics required from land to offshore and return, the operation has less environmental footprint, and the operation may pose less risk to personnel (risk from dropped objects/ fewer people in hazard zone).

An additional advantage is that the present invention's plug robot being an autonomous plug tool is that it may enables operators to secure the well without having an operational rig or a Wireline unit available eg. if the rig is experiencing technical problems like top drive broken down etc.; the plug may be released from a release position in the well and run autonomously either by gravity or by pumping to the target location and set itself commanded from remote such as from the surface.

Due to the versatile nature of the present invention's plug robot which is an autonomous plug tool, the core embodiment of the plug robot can be run in combination with auxiliary unit tools such as cutters, sensor packages etc. that can combine additional tasks in parallel with sealing and securing the well below the plug set, hence increasing operation efficiency by reducing total number of trips in the well for instance during plugand-abandonment operations.

In brief some advantages of the present invention are:

-The present invention is versatile and compatible with a range of standard and new conveyance methods for suspension plugs.

-The present invention reduces operational risk and required running time (lower operational cost, reduced rig time, footprint etc.).

-The present invention may reduce overall cost reduction for operators.

-The present invention may give improved of integration with other operator activities.

Short summary of the invention

A first aspect of the present invention is a petroleum well- (2) autonomous plug robot (1) comprising

- a command and control unit (11);

- at least one auxiliary tool unit (13);

- a packer unit (15) arranged for setting in a liner (4) or casing (3);

- an energy unit (17) for providing energy at least for setting said packer unit (15);

Please see the set of claims for further independent and dependent embodiments of the invention.

Figure captions

The attached figures illustrate some embodiments of the claimed invention.

Fig. 1a illustrates the plug robot (1) of the invention. The plug robot (1) is landed in a landing seat for being set at a target depth in a liner and then conduct auxiliary operations as cutting the liner.

Figs 2a, b, c, and d illustrates steps of an operation utilizing such an autonomous plug robot (1).

Fig. 2a shows a plug robot (1) initially conveyed on a drill pipe string (6) with an LHRT (61) run into hole (RIH) to a release position such as at a liner hanger with a releasable connector (53) from which the plug robot (1) is released to drop or be pumped or transported while not conveyed on any drill pipe string.

Fig. 2b shows the plug robot (1) released from the conveyor string and under way to the target location, here under gravity and / or pumping.

Fig. 2c shows the plug robot (1) landed in a target location, here a landing seat (134) in a liner e.g. in the form of a transition of liner Ø from 7 inches to 5 inches. The command and control unit has commanded the slips to set and then the packer elements to set. Fig. 2e shows the liner having been cut, the landing unit separated from the packer unit, and the liner being pulled up using the liner hanger retrieving tool LHRT.

Embodiments of the invention

The invention will in the following be described and embodiments of the invention will be explained with reference to the accompanying drawings.

The invention is a petroleum well- (2) autonomous plug robot (1) comprising - a command and control unit (11);

- one or more auxiliary tool unit (13);

- a packer unit (15) arranged for setting in a liner (4) or casing (3);

- an energy unit (17) for providing energy at least for setting said packer module (15). Please see Fig 1 for illustration of the plug robot (1) landed in a target positon in a liner. One may imagine an even simpler version of the plug robot (1) being without any auxiliary tool unit (13).

In an embodiment of the invention the energy unit (17) is arranged for further providing energy for activating and / or operating at least one of the auxiliary tool units (13). The setting of the slips and the packer elements may be either hydraulic or mechanical. For mechanical setting of the slips and packer elements an axial actuator may axially compress to force out the slips and then axially compress to expand the packer elements.

A further advantage of the invention is the fact that since the triggering of the plug robot (1) own setting of the slips and the plug without any drill pipe string manipulation, no drag blocks are required for creating any counterforce by dragging on the casing wall for activating the slips; the setting of the slips is initated and controlled by the control and command unit (11) and energy provided by the energy unit (17). This absence of drag blocks is a significant advantage during the pumping transport and particularly during gravity fall of the plug robot (1). It is even an advantage if the plug robot (1) is conveyed on drill pipe string on a releasable connector to its release point in the well, because the friction during the string conveyance without any drag blocks is reduced, and the risk of inadvertent shearing of shear pins thus triggering of the setting during drill pipe string conveyance, is no longer present.

In embodiments illustrated in Fig. 1a and Fig. 1b, the auxiliary tool unit (13) comprises a cutter tool (131).

In a further embodiment, the cutter tool (131) is a circumferentially cutting tool (132) for severing said liner (4) or casing (3), please see Fig. 1a, Fig. 1b, and Fig. 2d

In an embodiment of the invention the cutter tool (131) is a circumferentially cutting tool (132) arranged for cutting through around the entire wall perimeter of the liner (4) or casing (3) of the well (2). In an embodiment of the invention it may be a mechanical cutting tool. In another embodiment as shown in Fig. 1b it may be an explosive cutting tool which perforates and severs the liner. Both of those kinds of cutting tools are known per se.

The cutting tool (131) illustrated in Fig. 1a is a mechanical cutting tool (134). In an embodiment of the invention it is a mechanical cutting tool (134) comprising a drive motor (135) which may be electrically, mechanically, or hydraulically driven. In Fig. 1a is indicated a mud motor which operates on a mud pressure differential.

In an embodiment the cutting tool drive motor (135) is driven from said energy module (17).

In another embodiment the cutting tool drive motor (135) is a mud motor (136) driven by mud pressure.

In an alternative to a mechanically driven cutting tool (131, 134) a cutter tool (131) comprises an explosive charge (138), please see Fig. 1b. Such explosive charges for perforating a liner are well known in the petroleum industry. This explosive charge is triggered using a trigger unit (138T) which in a further embodiment may be arranged above the landing module

In an embodiment of the invention the cutting tool (131) arranged for separating, preferably explosively, from said packer module (15) when or after severing said liner (4).

In such an embodiment, at least a part of said auxiliary tool module (13) is arranged for separating from said packer module (15) after activation of said auxiliary tool module (13). This is not the same as separating due to releasing the upper releasable connector (5, 52) from the drill pipe string (6) with prefereably the LHRT (61) which is further up on the robot tool, and described below.

In an embodiment of the invention, the plug robot is such that one or more of said auxiliary tool units (13) comprises a predetermined landing module (133) for landing in a landing seat (134) or similar known restriction at a target location in said petroleum well. The known restriction in the well may be a crossover from a 7'' liner to a 5'' liner in the well.

In an embodiment the plug robot (1) is arranged for being pumped through said liner (4). Further, it may comprise a dart collar or packer (136) for slidingly sealing along said liner (4) wall (41) when being pumped along. In this way it may be pumped into deviated sections of the well.

In an embodiment of the invention we may pump the plug robot (1) through a part of the well which allows pumping of the tool. This may be a liner wherein the liner wall is somehow open below the plug, such as the liner being perforated below the target level below the plug under way. The plug may be pumped down by pumping it against a lower reservoir pressure around the liner. Alternatively, the plug may be transported along part of the path in the liner by gravity alone. This may be relevant for use in a vertical or near vertical well, wherein a roller section may be inserted in order to reducing the friction between plug and casing. In still another embodiment the plug robot (1) may be conveyed all or part of its way using a well tractor. Also here we may need roller sections. Such a well tractor may then be called an auxiliary unit (13) and may receive energy for its movement by the energy unit (17). Or it may be run on wireline or conveyed on a rod part of the way.

The plug may have bypass channels controlled by the command and control unit (11) to facilitate transport through the liner (4) when not being pumped. In this case, the well must have so-called injectivity to allow what is called "bullheading".

In another embodiment the plug robot (1) is arranged for being transported by gravity partly of or in combination with pumping.

In an embodiment of the invention the plug robot (1) may be provided with an upper releasable connector (5, 52) for being coupled to a corresponding drill pipe (6) borne connector (5, 51).

In this embodiment the drill pipe (6) borne connector (5, 51) is arranged for running the releasable connector (52) with the plug robot (1) into a release position in the casing (3) or liner (4), from which release position, the tool may take over and run autonomously further into the well to conduct a particular operation without being connected via the drill pipe string.

In an embodiment of the invention the conveying drill pipe (6) borne connector (5, 51) also comprises a liner hanger running tool (61). This connector is separating to launch the plug robot (1) due to releasing the upper releasable connector (5, 52) from the drill pipe string (6) with preferably the LHRT (61) which is further up on the robot tool than the separating explosive charge which allows leaving the packer unit shutting the well and allowing the liner above it to be pulled up.

In an embodiment of the invention the energy unit (17) comprises an electrical battery (171).

In embodiments of the invention the energy unit (17) may alternatively or additionally comprise mechanical and / or pressure energy units, such as a releasable pre-loaded spring, a pressure chamber with negative or positive pressure potential relative the well mud pressure (similar to a hydrostatic bailer or pressure tank). The energy unit (17) may also be chemically driven such as using a slow burning charge to create a fluid pressure to pressurize an oil reservoir.

In an embodiment of the invention the command and control module (11) is configured to control the packer, energy and aux module. The configuration depends on conveyance mode: real time surface control with WL (needs WL interface, electronic controller), digital SL and through-wired DP mode (needs WL interface, electronic controller); timer control and surface pressure induced trigger mechanism [TCP trigger] with pump-down and gravity fall mode.

In an embodiment of the invention the Control and Command unit (11) comprises a wireless signal receiving unit (111) for receiving command signals from higher up in said well (2), preferably from surface. One may command the control and command unit from surface by an initiation command signal such as 10 pressure pulses with given length and pressure differential, and then a specific command to trigger setting of the slips and the packers.

The Control and Command unit (11) may comprise a wireless signal transmission unit (112) arranged for sending control signals to higher up in said well (2), preferably to surface. The wireless signal receiving and transmission units (111, 112) may be hydraulic units which are arranged to receive and transmit based on pressure pulses transmitted in the mud. These pressure pulses may be transmitted via the drill pipe string, particularly simple if the drill pipe string (6) is connected to a liner hanger running tool LHRT (61) and the liner hanger seal is closed. In the same way as the downgoing signal, the upgoing signal to the surface may comprise a series of initation signals followed by a confirmation signal, a measurement signal, or similar signal to indicate whether the requested setting operation or other operation signal has been received, and also the outcome of the operation such as "set ok", "set failed", "pressure test conducted", "pressure test failed", "battery capacity remaining value", "battery failing", etc.

Command signals may be transmitted from the surface to release the upper releasable connector (52) from the drill pipe string borne connector (51) on the drill pipe string (6), i.e. after the LHRT (61) has been set on the liner hanger, thereby allowing the plug robot (1) to be launched from the connector (51) and starts its transport into the liner (4). The release to launch may be simpler and does not necessarily involve the command and control unit (11).

When the landing module (133) arrives at the landing seat or restriction (134) at its target depth, it will stop here. A sensor in the command and control unit or a pressure sensor at surface will indicate that the landing seat (134) has been reached, and a signal may be sent to surface.

When having reached its target depth in the well, the command and control module (11) may receive a command signal from surface for the packer module (15) to set. Preferably, the command and control module will activate the slips (151) and set those at the wall (41, 31) to immobilize the packer even when subject to pressure. When the slips (151) are set, the control module will control further setting of the packer elements (153). When the packer elements (153) are set, the packer may be pressure tested from above and below. In an embodiment of the invention the plug is provided with an axial passage with a controlled ball valve which may be opened and closed during pressure integrity testing. Energy for setting the slips and the packer elements (151, 153) are taken from the energy module (17). Control signals may be sent to the surface when the slips are set, when the packer elements are set, and optionally when the liner has been cut and the landing module has separated from the packer unit. In this way one may have some or all of the steps conducted by the autonomous plug unit confirmed at the surface.

When the packer is set, in an embodiment of the invention the cutting tool (131, 132, 135) may be activated to sever the liner (4) or casing (3) above the plug. The cutting tool may be arranged to disconnect itself from the packer module (15) automatically when having severed the liner (4) or casing (3).

After having severed the liner (4) as shown in Fig 2d, we may circulate the liner bottoms up to clean the annulus about the liner, and use the liner hanger running tool (61) to release the liner hanger and pull the severed part of the liner up or out of hole.

In an embodiment of the invention, any of said command unit (11), auxiliary tool unit (13), packer unit (15), energy unit (17) are modular units together constituting said plug robot (1).

In this way, the plug robot may be versatile as it is assembled from a general purpose energy unit (17) at the bottom, the packer unit (15) adapted to the relevant pipe diameters to be sealed, a general purpose control and command unit (11), and a preferred auxiliary tool unit (13) such as a pipe severing tool adapted to the relevant pipe diameters to be cut. If one is to conduct an operation in a well which requires setting a packer unit (15) but using an other or an additional auxiliary tool unit (13), such as the landing module, we just add and subtract relevant models with relevant diameters and functions to build up a versatile tool.

The essence of the invention may be that the autonomous plug robot (1) of the invention gets transported all or part of the way into a target position without the need of a conveying pipe string, into the well to set itself, as shown in the broken line rectangle of Figs. 2b and 2c. One may imagine the plug robot (1) being launched without being run on a drill pipe string (6).

Claims

1. A petroleum well- (2) autonomous plug robot (1) comprising

- a command and control unit (11);

- one or more auxiliary tool units (13);

- a packer unit (15) arranged for setting in a liner (4) or casing (3);

- an energy unit (17) for providing energy at least for setting said packer module (15).

2. The plug robot (1) of claim 1,

- said energy unit (17) further providing energy for activating and / or operating at least one of the auxiliary tool unit (13).

3. The plug robot (1) of claim 1 or 2, wherein

- said auxiliary tool unit (13) comprises a cutter tool (131).

4. The plug robot (1) of claim 3, wherein

- said cutter tool (131) is a circumferentially cutting tool (132) for severing said liner (4) or casing (3).

5. The plug robot (1) of claim 3 or 4, wherein

said cutting tool (131) is a mechanical cutting tool (134).

6. The plug robot (1) of claim 5, wherein said mechanical cutting tool (134) comprises a drive motor (135).

7. The plug robot (1) of claim 6, wherein said cutting tool drive motor (135) is driven from said energy module (17).

8. The plug robot (1) of claim 13, wherein said cutting tool drive motor (135) is a mud motor (136) driven by mud pressure.

9. The plug robot of claim 3 or 4, wherein said cutter tool (131) comprises an explosive charge (138).

10. The plug robot (1) of claim 9 or claims 4 - 8,

said cutting tool (131) arranged for separating, preferably explosively,

from said packer module (15) when or after severing said liner (4).

11. The plug robot of any of the preceding claims, wherein

one or more of said auxiliary tool units (13) comprises

- a predetermined landing module (133) for landing in a landing seat (134) or similar known restriction at a target location in said petroleum well.

12. The plug robot (1) of any of the preceding claims,

- said plug robot (1) arranged for being pumped through said liner (4).

13. The plug robot (1) of claim 12,

- said plug robot (1) comprising a dart collar or packer (136) for slidingly sealing along said liner (4) wall (41).

14. The plug robot (1) of any of the preceding claims,

-said plug robot (1) is arranged for being transported by gravity.

15. The plug robot of any of the preceding claims,

provided with an upper releasable connector (5, 52) for being coupled to a corresponding drill pipe (6) borne connector (5, 51).

16. The plug robot (1) of claim 15,

said drill pipe (6) borne connector (5, 51) also comprising a liner hanger running tool (61).

17. The plug robot (1) of any of the preceding claims, wherein said energy unit (17) comprises an electrical battery (171).

18. The plug robot (1) of any of the preceding claims,

- said Control and Command unit (11) comprising a wireless signal receiving unit (111) for receiving command signals from higher up in said well (2), preferably from surface.

19. The plug robot (1) of any of the preceding claims, comprising

- said Control and Command unit (11) comprising a wireless signal transmission unit (112) arranged for sending control signals to higher up in said well (2), preferably to surface.

20. The plug robot (1) of any of the preceding claims, wherein any of said command unit (11), auxiliary tool unit (13), packer unit (15), energy unit (17) are modular units constituting said plug robot (1).

21. A method of plugging a well, comprising

- launching a petroleum well- (2) autonomous plug robot (1) comprising

- a command and control unit (11);

- one or more auxiliary tool units (13);

- a packer unit (15) arranged for setting in a liner (4) or casing (3);

- an energy unit (17) for providing energy at least for setting said packer module (15),

- transporting said plug robot (1) to a target depth in said liner or casing (4, 3) without conveying it on a string,

- transmitting a signal to said command and control unit (11) to activate and set said packer unit (15) in said liner or casing (4, 3);

- transmitting a signal to said command and control unit (11) to activate and use said one or more auxiliary tool units (13).

22. The method of claim 21,

- using said tool unit (13) to cut said liner above said packer module (15).

23. The method of claim 22,

- after cutting said liner (4), pulling the liner above said packer module (15) out of hole.

24. The method of any of claims 21 - 23,

- running said plug robot (1) on a drill pipe string liner hanger running tool (61) into a liner hanger,

- connecting said liner hanger running tool (61) to said liner hanger,

- releasing said plug robot (1) from said liner hanger running tool (61) and transporting said plug robot further into said liner (4) to a target depth,

- sending signals to said command and control unit (11) to activate and set said packer unit (15)