GB2513934A

GB2513934A - Downhole tool system

Info

Publication number: GB2513934A
Application number: GB1317672.2A
Authority: GB
Inventors: Iain Maxted; Jonathan Gore; Paul Bennett; Arturs Elksnis
Original assignee: Guardian Global Technologies Ltd
Current assignee: Guardian Global Technologies Ltd
Priority date: 2013-10-07
Filing date: 2013-10-07
Publication date: 2014-11-12
Anticipated expiration: 2033-10-07
Also published as: GB201317672D0; GB2513934B

Abstract

Configuring a downhole tool string where a control signal leaves only the first of the tools 100 in communication with a control unit 12involves the control unit 12 sending an identification query to the first tool 100; where the first tool 100 responds to the query and the control unit 12 associates the signal with a first address which is then transmitted to the first too1 100; the control unit 12 then sends a close signal to the first tool 100 and repeats said step with each of the tools 200, 300.

Description

-I -

Downhole Tool System

Field of the Invention

The present invention concerns a downhole tool system.

More particularly, but not exclusively, this invention concerns a method and apparatus for data transmission from a downhole tool system to surface and vice versa. The invention also concerns a system for downhole data transmission and a method of configuring the system.

Background of the Invention

It is desirable to be able to transmit data to and from one or more downhole tools, a toolstring', being used in oil and gas wells. Such tools may be, but are not exclusively, used to deploy ballistics devices within the well-bore, these being known as ballistics delivery tools.

The data being transmitted may be related to one or more sensors deployed in the toclstring, and/or command and control data being sent to downhcle tools to control their operation. In order to successfully control a dcwnhole tool operation, it may be necessary to know the relative location of a downhole tool in the toolstring. One way in which this may be achieved is for each dcwnhole tool to be pre-configured with address information in the factory, with the user required to manually enter the relative order of tools within the toolstring into a surface control unit. With increasingly sophisticated and complex toolstring configurations there is a risk that during the on-site assembly of the tool string, an error occurs and the individual downhole tools are arranged in the wrong order.

Once the tool string is in operation, the control unit may not detect the Incorrect configuration, with the potential that downhole errors occur. In a ballistics operation, this could result in the ballistics being detonated at the wrong depth and thus jeopardising the well integrity.

The present invention seeks to mitigate the above-mentioned problems. Alternatively or additionally, the present invention seeks to provide an improved downhole tool and system of data transmission.

Summary of the Invention

The invention provides, according to a first aspect, a method of configuring a downhole tool string, the downhole tool string comprising: a data transmission system comprising a control unit, and a surface to downhole cable, and a plurality of downhole tools connected in a contiguous, series arrangement to the cable, each downhole tool comprising a switch configured to enable (CLOSE) or disable (OPEN) a signal sent from the control unit from passing along the cable to the adjacent, downstream, downhole tool, the method comprising the steps of: the control unit sending an OPEN signal to the plurality of downhole tools, thereby leaving only the first of the plurality of tools in communication with the control unit, the control unit sending an identification query (IOENTIFY)to the first of the plurality of tools, the first of the plurality of tools responding to the identification query by sending the control unit an identification signal, whereby the control unit associates the identification signal with a first address, the control unit sending an address (001) to the first of the plurality of tools together with a CLOSE signal to the switch of the first downhole tool, thereby establishing communication with both the first and the second downhole tools, the control unit sending an identification query to the second of the piuraiity of tools, the second of the plurality of tools responding to the identification query by sending the control unit an identification signal, thereby the control unit associating the identification signal with a second address (002), and the control unit repeating the CLOSE and IDENTIFY signals until each of the plurality of downhole tools has been allocated an address.

Advantageously, the method allows the self-configuration of a downhole tool string in situ. This may provide a more flexible system than the manually configured prior art systems. A tool string may be created on site, and the self-configuration of the tool string in situ may reduce the time required when commissioning a new tool string.

The identification signal provided by each of the downhole tools may comprise information relating to the type of downhole tool from which the signal is sent. For example, the downhole tool may be a ballistics delivery tool, and the information may relate to the properties of the ballistics delivery tool. The information provided by each downhole tool may be recorded and associated with the address of the downhole tool. The method may include the step of comparing the tool string configuration to one or more allowable tool string configurations. The method may include the step of activating an alarm if the tool configuration does not match any of one or more allowable tool string configurations. Advantageously, this may prevent the use of a tool string which has been incorrectly configured, thus potentially preventing damage to the well operation or tool string.

According to a second aspect, the invention provides a downhole tool comprising: a power input, the power input configured for connection with a downhole cable, a power output, the power output configured for connection with a downhole cable, and an electronic switch, the electronic switch configured to enable or disable the transmission of power from the power input to the power output in response to commands received via the power input.

The downhole tool may comprise a tool control unit, the control unit configured to control the operation of the downhole tool. For example, the control unit may be configured to control the detonation of a ballistics delivery tool.

The downhole tool may comprise an identity module, the identity module including information relating to the downhole tool.

According to a third aspect, the invention provides a downhole tool system comprising: a first downhole tool and a second downhole tool, the first downhole tool connected in series with the second downhole tool, each downhole tool comprising a power input and a power output, the power output of the first downhole tool connected to the power input of the second downhole tool via a downhcie cable, the first downhole tool further comprising a first switch configured to enable or disable the transmission of power from the power input of the first downhole tool to the power output of the first downhole tool, such that the first switch also enables or disables the transmission of power from the first downhole tool to the second downhole tool.

The downhole tool system may comprise a surface control unit, the surface controi unit arranged to provide control signals to the first downhole tool and second downhole tool.

The surface control unit may be arranged to control the operation of the first switch to enable or disable the transmission of power from the first downholLe tool to the second downhole tool.

The first downhole tool and second downhole tool each comprise an identity module, each identity module comprising information regarding the associated downhole tool.

Each address module may be configured to transmit data to the surface control unit.

The surface control unit may comprise a display interface.

According to a fourth aspect, the invention provides a downhole tool system comprising: a downhole tool string including a first downhole tool and a second downhole tool, and a surface control unit, wherein the surface control unit is connected to the first and second downhoie tools via a surface to downhole cable, and the surface control unit comprises a computer readable medium including a computer program configured such that when run on the surface control unit, the downhoie tool string is configured according to the method as described above.

According to a fifth aspect, the invention provides a computer program, the computer program when run on a surface control unit configured to configure a downhole tool sting as described according to second, third, or fourth aspect of the invention, according to the method as described according to the first aspect of the invention.

It will of course be appreciated that features described in relation to one aspect of the present invention may be incorporated into other aspects of the present invention. For example, the method of the invention may incorporate any of the features described with reference to the apparatus of the invention and vice versa.

Description of the Drawings

Embodiments of the present invention will now be described by way of example only with reference to the accompanying schematic drawings of which: Figure 1 shows a schematic view of a first and second downhoie tool according to a first embodiment of the invention; and Figure 2 shows a schematic view of a downhole tool string according to a second embodiment of the invention.

Detailed Description

Figure 1 shows a downhole tool system comprising a first and second downhole tool according to a first aspect of the invention. The first tool 100 and second tool 200 are connected in a tool string. A downhole to surface cable is run from a surface control unit (not shown In figure 1) to the first tool 100 and the second tool 200. Both the first tool 100 and second tool 200 each comprise a switch 102, 202, controlled by signals received from the surface control unit, along the cable 10. The switch 102, 202, is an electronic switch that can be open or closed under control of the tool system electronics, and is configured to enable or disable the power feed from the cable 10, to the next, consecutive, tool. Each tool 100, 200, comprises an input connected to the cable 10 and an output connected to the cable 10. The tools 100, 200, are contiguous with the cable 10 and connected in series, such that if the switch 102 is open, data transmission (via a power signal) to the second tool 200 is disabled, and if the switch 102 is closed, data transmission to the second tool 200 is enabled.

The first tool 100 and second tool 200 may be arranged such that the switch 102, 202, opens and closes only during the configuration of the tool string as will be further detailed below. The cable 10 is arranged such that in order for power to be supplied to the second tool 200, the switch 102 has to be in the closed position (in response to a CLOSE command), in order that the power may flow through the first tool 100 and on to the second tool 200. This arrangement is clearly shown in figure 1. As can be seen in the first tool 100, and as is replicated in the second tool 200 (but not fully shown) , the tool 100 comprises a voltage sense and tool power switch circuit 104 running off the cable 10 upstream of the location of the switch 102, the voltage sense and tool power switch circuit 104 connected to a voltage regulator 106 and a communications unit 108. A switch bias circuit 110 is connected to the switch 102, and also to a control unit 114 which is arranged to control the tool function 116. The tool function 116 may, for example, be a ballistics delivery tool, and the control unit may control the detonation of the ballistics delivery tool.

The tool string may comprise a number of tools, for example, any number from 2 to 40 (or more) tools, arranged by simple repetition of the series arrangement shown in figure 1. In alternative embodiments, there may be a greater number of tools, and aspects of the invention are equally applicable whatever the number of tools in a tool string.

Figure 2 shows a schematic view of a downhole tool string and control system according to an embodiment of the invention. A surface control unit 12, which comprises a computer processing unit, is connected by the cable 10 to a first downhole tool 100. A second tool 200 and third tool 300 are connected to the first tool 100 in such a way as described in more detail with regards to figure 1. The surface control unit 12 may communicate with the second tool via the first tool 100, provided the switch 102 is closed, and similarly the surface control unit 12 may comunicate with the third tool 300 via the first tool 100 and second tool 200 provided the switches 102 and 202 are closed. The third tool 300 also includes a switch 302, which may enable communication with a fourth tool should one be present, and so on. The surface control unit 10 may comprise a display unit 14, such as a computer display monitor, configured to display information regarding the tools comprising the tool string. The control unit 10 may also comprise a user input device 16, such as a keyboard, to enable a user to send coands to the downhole tools comprising the tool string. The control unit 10 may comprise a computer program for running a configuration program either automatically or in response to a user input to the control unit 10. The computer program may be stored on a computer readable medium, such as a computer hard drive, a CD-ROM, or a [JSB device. The skilled person will appreciate that any suitable computer readable medium may be used.

The tool string as described with reference to figures 1 and 2 may be configured according to the following method.

During power up of the cable 10, the switches 102, 202, are "closed" and all tools are powered in the string. In order to initiate a self-configuration, an "open" switch command is sent by the surface control unit to all tools in the string, with those tools then opening their respective smart switches. At this point, only the first tool 100 on the cable 10 will be powered, as the smart switch 102 has disabled power to the second tool 200. Communication between the surface control unit 12 and the first tool 100 may then begin. The surface control unit 12 sends the first tool a data transmission comprising an "identify" command.

The communication unit 108 of the first tool 100 may then respond to the "identify" command by sending an identification signal to the surface control unit. The surface control unit 12, will then send a "set address" command together with the address [0001] . Thereby, the first tool 100 may be assigned an address [0001], which is recorded by the surface control unit 12 and the first tool control unit 114. Thereafter, communications sent to the first tool 100 will be preceded by the address [0001], which indicates to the first tool 100 that the command signal is intended for that tool. A tool with an address other than [0001] will ignore the command. This allows, once a tool string has been configured, the signal sent -10 -along the cable 10 be seen by each of the downhole tools, but only the intended tool acting on the command signal.

Having assigned an address to the first tool 100, the surface control unit sends a "close" signal to the smart S switch 102. The cable 10 then powers the second tool 200.

An "identify" command is sent via the cable 10 as before, and the second tool 200 is allocated an address [0002], whereby the second tool 200 responds to the "set address" [0002] command with a confirmation signal. The process may be repeated until every tool of a tool string has been allocated an address from [0001] to [nnnn] . When responding to the "identify" signal, the communications unit of a tool may also send information regarding the type, configuration and calibration data of the tool, for example, it may specify that the tool is a ballistics delivery tool including for example, information concerning the ballistics included in the tool.

The surface control unit 12 may record and store the tool string configuration data in order to be able to send control commands to the correct tool making up a tool string. For example, it may be required to send a control signal to the second tool 200, and any control signal may be preceded by the address information [0002] . The tool string configuration data may also be analysed by a compatibility unit present in the surface control unit 12. The compatibility unit may comprise a database of acceptable tool string configurations. The tool string analysis may compare the received data concerning tool string configuration to the database of acceptable configurations and send a warning message via the display screen 14 should the tool string not correspond to an acceptable configuration. The surface control unit 12 may also prevent -11 -any coands being sent to a tool string should it detect that the configuration of the tool string is unacceptable.

This may prevent the incorrect operation of the tool string resulting in safety hazards or damage to the well environment.

The surface control unit may comprise a graphical interface on a display 14, whereby the tool configuration data may be shown to a user, the tool configuration data including the sequence of the tools connected in the tool string, the type of each of the tools, the tool serial number, and any other desirable tool data. Such an arrangement may increase the ease of use of the downhole tool string.

Whilst the present invention has been described and Illustrated with reference to particular embodiments, it will be appreciated by those of ordinary skill in the art that the invention lends itself to many different variations not specifically illustrated herein.

Where in the foregoing description, integers or

elements are mentioned which have known, obvious or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present invention, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the invention that are described as preferable, advantageous, convenient or the like are optional and do not limit the scope of the independent claims. Moreover, it is to be understood that such optional integers or features, whilst of possible benefit in some embodiments of the invention, may not be -12 -desirable, and may therefore be absent, in other embodiments.

Claims

-13 -Claims 1. A method of configuring a downhole tool string, the downhole tool string comprising: a data transmission system comprising a control unit, and a surface to downhole cable, and a plurality of downhole tools connected in a contiguous, series arrangement to the cable, each downhole tool comprising a switch configured to enable (CLOSE) or disable (OPEN) a signal sent from the control unit from passing along the cable to the adjacent, downstream, downhoie tool, the method comprising the steps of: the control unit sending an OPEN signal to the plurality of downhoie tools, thereby leaving only the first of the plurality of tools in communication with the control unit, the control unit sending an identification query (IDENTIFY) to the first of the plurality of tools, the first of the plurality of tools responding to the identification query by sending the control unit an identification signal, whereby the control unit associates the identification signal with a first address which is transmitted to the first of the plurality of tools, the control unit sending a CLOSE signal to the switch of the first downhole tool, thereby establishing communication with both the first and the second downhole tools, the control unit sending an identification query to the second of the plurality of tools, the second of the plurality of tools responding to the identification query by sending the controi unit an -14 -identification signal, thereby the control unit associating the identification signal with a second address which is transmitted to the second of the plurality of tools, and the control unit repeating the CLOSE and IDENTIFY signals until each of the plurality of downhole tools has been allocated an address.
2. A method as claimed in claim 1, wherein the identification signal provided by each of the downhole tools comprises information relating to the type of downhole toci from which the signal is sent.
3. A method as claimed in claim 1 or claim 2, further comprising the step of comparing the tool string configuration to one or more allowable tool string configurations.
4. A method as claimed in claim 3, comprising the step of activating an alarm if the tool configuration does not match any of one or more allowable tool string configurations.
5. A downhole tool comprising: a power input, the power input configured for connection with a downhole cable, a power output, the power output configured for connection with a downhole cable, and an electronic switch, the switch configured to enable or disable the transmission of power from the power input to the power output in response to commands received via the power input.

-15 -
6. A downhole tool as claimed in claim 5 further comprising a tool control unit, the tool control unit configured to control the operation of the downhole tool.
7. A downhole tool as claimed in claIm 5 or claim 6, further comprising an identity module, the identity module including information relating to the downhole tool.
B. A downhole tool system comprising: a first downhole tool and a second downhole tool, the first downhole tool connected in series to the second downhole tool, each downhole tool comprising a power input and a power output, the power output of the first downhole tool connected to the power input of the second downhole tool via a downhole cable, the first downhole tool further comprising a first switch configured to enable or disable the transmission of power from the power input of the first downhole tool to the power output of the first downhole tool, such that the first switch also enables or disables the transmission of power from the first downhole tool to the second downhole tool.
9. A downhole tool system as claimed in claim 8, further comprising a surface control unit, the surface control unit arranged to provide control signals to the first downhole tool and second downhole tool.
10. A downhole tool system as claimed in claim 9, wherein the surface control unit is arranged to control the operation of the first switch to enable or disable the -16 -transmission of power from the first downhole tool to the second downhole tool.
11. A downhole tool system as claimed in any of claims 8 to 10, wherein the first downhole tool and second downhole tool each comprise an identity module, each identity module comprising information regarding the associated downhcle tool *
12. A downhole tool system as claimed in claim 11, wherein each identity module is configured to transmit data o the surface control unit.
13. A downhole tool system as claimed in any of claims 9 to 12, wherein the surface control unit comprises a display interface.
14. A downhole tool system comprising: a downhole tool string including a first downhole tool and a second downhole tool, and a surface control unit, wherein the surface control unit is connected to the first and second downhole tools via a surface to downhole cable, and the surface control unit comprises a computer program configured such that when run on the surface control unit, the downhole toolstring is configured according to the method as claimed in claim 1.
15. A computer program, the computer program when run on a surface control unit configured to configure a downhole tool -17 -string as claimed in claim 8, according to the method as ciaiw.ed in claim 1.
16. A method of configuring a downhole tool string substantially as herein described with reference to any of Figs. 1 and 2 of the accompanying drawings.
17. A downhoie tool substantially as herein described with reference to any of Figs. 1 and 2 of the accompanying drawings.