BACKGROUND

Fluid sampling tool strings are used to collect fluid samples from open boreholes or cased boreholes. The collected fluid samples may be used, for example, to verify the quality of formation fluids before production begins or to investigate the source of water or contaminants during production. Collecting multiple samples in a single run can reduce costs (by reducing the amount of production downtime), but increases complexity of the fluid sampling process. In particular, controlling the timing of different fluid samplings in a cased borehole environment is an ongoing challenge because there is insufficient space for communication/control wires to reach multiple fluid samplings. One way to control different fluid samplings in a single run involves using timers set to different values. To ensure samples are not collected too early (e.g., before a fluid sampling has reached a target position), a generous time delay can be used between sampling operations. However, this strategy increases costs (by increasing the amount of production downtime).

BRIEF DESCRIPTION OF THE DRAWINGS

Accordingly, there are disclosed in the drawings and the following description a fluid sampling tool string with acoustic signaling. In the drawings:

FIG. 1 is an illustrative diagram of an illustrative wireline fluid sampling tool string environment.

FIG. 2 is a schematic diagram of an illustrative control module for the fluid sampling tool string of FIG. 1.

FIG. 3 is a schematic diagram of an illustrative fluid sampling/adapter assembly. FIG. 4 is an illustrative diagram of an alternative fluid sampling tool string employing mechanical adapters, supplemental controllers, and a non-sampling tool.

FIG. 5 is a flow block diagram of a method involving a wireline fluid sampling tool string with acoustic signaling. DETAILED DESCRIPTION

Disclosed herein are methods and systems involving a fluid sampling tool string with acoustic signaling. The fluid sampling tool string includes a plurality of fluid sampling modules and, as desired, receives power or telemetry signals from a surface interface. In different embodiments, the fluid sampling tool string is deployed downhole via wireline, slickline, coiled tubing, or another connection line. Telemetry signals transmitted between the surface interface and the fluid sampling tool string may correspond to electrical signals, optical signals, acoustic signals, or other known telemetry signals. In response to receiving power and/or telemetry signals from the surface interface, the fluid sampling tool string initiates a fluid sampling process in realtime or in a delayed manner (e.g., by storing instructions for later). To trigger fluid sampling operations by one or more of its fluid sampling modules, the fluid sampling tool string transmits a downlink acoustic signal through an acoustic channel formed by components of the wireline fluid sampling tool string (e.g., tool bodies of the fluid sampling modules and possibly adapters connecting the fluid sampling modules together). In some embodiments, an operator on earth's surface may instruct the fluid sampling tool string to initiate fluid sampling operations in response to determining that a fluid sampling module is at a target position or depth along a cased borehole. Alternatively, the fluid sampling tool string may initiate fluid sampling operations in response to measurements collected by one or more sensors included with the fluid sampling tool string. In either case, the fluid sampling tool string employs acoustic signaling to collect multiple fluid samples in a single run without unnecessary time delays or production downtime.

In at least some embodiments, an example method includes deploying a fluid sampling tool string downhole, the fluid sampling tool string including a control module and a plurality of fluid sampling modules. The method also includes receiving, by the control module, a telemetry signal from a surface interface. The method also includes transmitting, by the control module, a downlink acoustic signal based at least in part on a received telemetry signal. The method also includes initiating a fluid sampling operation, by at least one of the plurality of fluid sampling modules, in response to the downlink acoustic signal.

Meanwhile, an example system includes a fluid sampling tool string deployed downhole via a wireline, where the fluid sampling tool string includes a control module and a plurality of fluid sampling modules. The system also includes a surface interface in communication with the fluid sampling tool string, where the control module is configured to receive a telemetry signal from the surface interface and to transmit a downlink acoustic signal based at least in part on the telemetry signal. At least one of the plurality of fluid sampling modules initiates a fluid sampling operation in response to the downlink acoustic signal. Various tool string deployment options, surface-to-tool telemetry options, and fluid sampling tool string options are described herein.

FIG. 1 is an illustrative diagram of a fluid sampling tool string environment. In environment 100, a fluid sampling tool string 101 is deployed in a cased borehole 104 via a connection line 120. The connection line 120 may correspond to a wireline, a slickline, a coiled tubing, or other available connection lines. In FIG. 1, the cased borehole 104 includes a casing string 106 that extends to or through oil-producing or gas-producing zones 110 and 112 (i.e., the cased borehole 104 may be used as a production well). The connection line 120 and rig (or other surface equipment) 126 enables the fluid sampling tool string 101 to be "run in hole" (RIH) or "pool out of hole" (POOH) in the cased borehole 104 as desired. Further, the connection line 120 may form part of a telemetry channel between the fluid sampling tool string 101 and a surface interface 108 on the earth's surface 102. In different embodiments, the telemetry channel between the fluid sampling tool string 101 and the surface interface 108 enables downlink and/or uplink electrical signaling, optical signaling, acoustic signaling, or other known telemetry options. The surface interface 108 is connected to a computer 105 which enables automated operations, user-based operations, display of collected information, display of fluid sampling options, and/or other features related to the fluid sampling tool string 101.

In at least some embodiments, the fluid sampling tool string 101 comprises individual modules coupled together. The modules may include a control module 130 and a plurality of fluid sampling modules 150A-150C. Further, in some embodiments, a plurality of mechanical adapters 140A-140C may be used to different modules together. Each mechanical adapter 140A-140C may join two modules together (supporting the weight of other components of the fluid sampling tool string 101). Further, each mechanical adapter 140A-140C may provide a pivot point or flexing point to enable bending along the fluid sampling tool string 101.

In FIG. 1, the control module 130 of the fluid sampling tool string 101 is physically coupled to the connection line 120. In different embodiments, power and/or downlink telemetry signals may be conveyed from the surface interface 108 to the fluid sampling tool string 101 via a telemetry channel that may include the connection line 120. Further, uplink telemetry signals may be conveyed from the fluid sampling tool string 101 to the surface interface 108 via the telemetry channel that may include the connection line 120. As needed, a wireline, slickline, or coiled tubing can be customized to support electrical signaling, acoustic signaling, optical signaling, or other telemetry options. Example downlink telemetry signals include commands for one or more of the fluid sampling modules 150A-150C. Meanwhile, example uplink telemetry signals includes acknowledgements, sensor data, and status information from the control module 130 or fluid sampling modules 150A-150C. In some embodiments, other components (e.g., supplemental controllers and/or non-sampling tools) may be included with the fluid sampling tool string 101 and may transmit or receive telemetry signals. Connected to a lower end of the control module 130 is mechanical adapter 140 A, which couples the control module 130 to the fluid sampling module 150A by any conventional means including, but not limited to, threads, a flexible u-joint, or screws. Each of the mechanical adapters 140A-140C may be rigid in some embodiments. Alternatively, one or more of the mechanical adapters 140A-140C may allow for some flexibility or movement of the control module 130 in relation to the fluid sampling modules 150A-150C to facilitate passage of the fluid sampling tool string 101 past curves and bends in the cased borehole 104. Another option is to couple the control module 130 and different fluid sampling modules (e.g., modules 150A-150C) directly such that one or more of the adapters 140A- 140C are omitted.

While three fluid sampling modules 150A-150C and three adapters 140A-140C are represented for the fluid sampling tool string 101 of FIG. 1, it should be appreciated that fewer or additional fluid sampling modules or modules are possible. Regardless of the number of fluid sampling modules or modules included with the fluid sampling tool string 101, an acoustic channel is formed by components of the fluid sampling tool string 101 (e.g., by module tool bodies and/or adapter materials) such that downhole acoustic signaling or uplink acoustic signaling is possible. For example, the control module 130 may convey downlink acoustic signals through the acoustic channel provided by the fluid sampling tool string 101 to direct the fluid sampling modules 150A-150C to initiate fluid sampling operations. As another example, the fluid sampling modules 150A-150C may convey uplink acoustic signals through the acoustic channel provided by the fluid sampling tool string 101 to report acknowledgements, status information, or sensor measurements to the control module 130. As needed, additional components for supplementary uplink signaling or supplementary downlink signaling may be employed by the fluid sampling tool string 101 depending on the acoustic transceiver used and acoustic channel characteristics as described herein.

In operation, the control module 130 may receive power and/or control signals from the surface interface 108 via the connection line 120. In response to the power and/or control signals available via the connection line 120, the control module 130 transmits a downlink acoustic signal that travels through the acoustic channel provided by the fluid sampling tool string 101. The downlink acoustic signal can be transmitted with or without delay relative to when power and/or control signals are received from the surface interface 108. In response to receiving the downlink acoustic signal, each of the fluid sampling modules 150A-150C selectively initiates fluid sampling operations. As desired, one of the fluid sampling modules 150A-150C or a plurality of the fluid sampling modules 150A-150C may operate at a given time. For example, an addressing scheme may be employed with the acoustic signaling described herein to direct communications to one or more components of the fluid sampling tool string 101. For all embodiments described in this document, the use of the terms "upper" and "lower" in this document are meant to express the relative ends of various modules that are closer to (upper), or furthest from (lower), the connection line 120 even though some cased boreholes 104 may include horizontal or angled sections.

FIG. 2 is a schematic diagram of control module 130. As shown, the control module 130 may include a signal transceiver 132, sensor(s) 136, and an acoustic signal transceiver 134. In different embodiments, the signal transceiver 132 may correspond to an electrical signal transceiver, an acoustic signal transceiver, or an optical signal transceiver. In at least some embodiments, the acoustic signal transceiver 134 includes an uplink acoustic receiver 138 and a downlink acoustic transmitter 142 that supports full duplex or half duplex communication via uplink acoustic reception and downlink acoustic transmission. In an alternative embodiment, the acoustic signal transceiver 134 may combine the functionality of the uplink acoustic receiver 138 and the downlink acoustic transmitter 142 into a single component capable of both transmitting and receiving acoustic signals. In such a case, acoustic signal transmissions and receptions would be half duplex. As needed or as programmed, the signal transceiver 132 receives telemetry signals from and transmits telemetry signals to the surface interface 108 of FIG. 1. In order to perform its operations (e.g., receiving, transmitting, and decoding of telemetry signals or acoustic signals), the control module 130 may use electrical power received in real-time from the surface interface 108 via the connection line 120 (e.g., if the connection line 120 includes an electrical conductor). As needed, the control module 130 may include a remote power source 144, which may take the form of a battery, capacitive cells, or other forms of energy storage. In some embodiments, the remote power source 144 provides power while the fluid sampling tool string 101 is deployed downhole such that a power cable between the surface interface 108 and the fluid sampling tool string 101 in not needed. If a power cable is available along the connection line 120, the remote power source 144 can be charged or re-charged using power received from the surface interface 108 via the connection line 120.

The sensor(s) 136 represented in FIG. 2 are optional, and may be used in combination with, or instead of, control signals from surface interface 108. Example sensor(s) 136 include position sensors, flow sensors, temperature sensors, and/or other sensors whose measurements may be used to identify when the fluid sampling tool string 101 or an individual fluid sampling module is at a target position. In operation, the downlink acoustic transmitter 142 of the control module 130 transmits a downlink acoustic signal 116 in the 10 Hz - 20 KHz range. The downlink acoustic signal 116 propagates through the acoustic channel provided by the fluid sampling tool string 101 to the fluid sampling modules (e.g., modules 150A-150C), non-sampling tool(s) (described later), or other components of the fluid sampling tool string 101. While not represented in FIG. 2, the uplink acoustic receiver 138 of the control module 130 may receive uplink acoustic signals via the same acoustic channel from fluid sampling modules (e.g., modules 150A-150C), non-sampling tool(s), or other components of the fluid sampling tool string 101. In response to the uplink acoustic signals or other operations performed by the control module 130, control circuitry (not shown) may direct the signal transceiver 132 to transmit a telemetry signal to the surface interface 108 or may direct the acoustic signal transceiver 134 to transmit additional downlink acoustic signals.

FIG. 3 is a schematic diagram of a fluid sampling / adapter assembly 128. The fluid sampling / adapter assembly 128 includes a fluid sampling module 150 and a mechanical adapter 140. In at least some embodiments, the fluid sampling module 150 is a commercially-available fluid sampling tool customized to include an acoustic signal transceiver 164. Suitable fluid sampling tool options are described in U.S. Pat. No. 7,472,589 B2 titled "Single Phase Fluid Sampling Apparatus And Method For Use of Same" and U.S. Pat. No. 7,874,206 B2 also titled "Single Phase Fluid Sampling Apparatus And Method For Use of Same". The acoustic signal transceiver 164 enables the fluid sampling module 150 to receive downlink acoustic signals from the control module 130 of FIG. 2 and to transmit uplink acoustic signals (e.g., status signals, sensor signals, or other signals) to the control module 130. The fluid sampling module 150 includes a storage chamber, a fluid port 154, and/or other components to collect and store a quantity of borehole fluids. The fluid sampling operations associated with the fluid sampling module 150 are initiated, for example, by control electronics (not shown) of the fluid sampling module 150 in communication with the acoustic signal transceiver 164. As an example, the control electronics can initiate fluid sampling operations in response to receiving downlink acoustic signal 116 of FIG. 2. The fluid sampling adapter module 150 may include a remote power source 175 which may take the form of a battery, capacitive cells, or other forms of energy storage.

In some embodiments, the fluid sampling module 150 may optionally include sensor(s) 136 to collect measurements such as position, pressure, or temperature. The measurements collected by sensor(s) 136 may be used by the fluid sampling module 150 to initiate or monitor fluid sampling operations. Additionally or alternatively, measurements collected by sensor(s) 136 may be included in an uplink acoustic signal sent from the acoustic signal transceiver 164 to the control module 130. Any information provided with the uplink acoustic signal may be analyzed by the control module 130 and/or may be conveyed to the surface interface 108 for analysis. In different embodiments, such sensor(s) 136 may be included with the control module 130, fluid sampling module 150A-150C, supplemental control module 176, mechanical adapter 140, or a non-sampling downhole tool. Measurements from the sensor(s) 136 may influence the timing or position at which fluid sampling operations are performed by the fluid sampling tool string 100.

In some embodiments, the mechanical adapter 140 is a passive mechanical device for coupling two different modules together. In an alternative embodiment, as in FIG. 3, the mechanical adapter 140 may include a supplemental control module 176, which includes an uplink acoustic receiver 168, control circuitry 178, and a downlink acoustic transmitter 172. As needed or as programmed, the uplink acoustic receiver 168 generates a supplemental uplink acoustic signal 124 that propagates via the acoustic channel of the fluid sampling tool string 101 to the control module 130 or another supplemental control module. Similarly, as needed or as programmed, the downlink acoustic receiver 172 generates a supplemental downlink acoustic signal that propagates via the acoustic channel of the fluid sampling tool string 101 to one or more fluid sampling modules or another supplemental control module.

Adding a supplementary control module 176 may help ensure uplink or downlink acoustic signals reach their intended destinations. As needed, uplink or downlink acoustic signals can be received and re-transmitted as amplified versions of the received signals. Additionally or alternatively, each supplemental control module 176 may transmit new uplink or downlink acoustic signals by decoding received signals and generating new signals in accordance with the decoded information. The control circuitry 178 may be used, for example, to decode or process information from received signals and to select options for transmitting new uplink or downlink acoustic signals. The signals transmitted from the supplemental control modules are termed supplemental downlink acoustic signals or supplemental uplink acoustic signals herein to differentiate them from downlink acoustic signals transmitted by the control module 130 and uplink acoustic signals transmitted by a fluid sampling module 150. The supplementary control module may include a remote power source 185 which may take the form of a battery, capacitive cells, or other forms of energy storage.

For fluid sampling tool string embodiments that include a plurality of fluid sampling modules and a plurality of supplementary control modules, an addressing scheme may be employed to direct signals to the different fluid sampling modules or supplementary control modules. Accordingly, each fluid sampling module or supplementary control module can perform an address verification function upon receiving downlink or uplink acoustic signals. For example, the control module 130 or the supplemental control module 146, as desired, may address signals to specific fluid sampling modules 150A-15C to initiate fluid sampling operations. Other fluid sampling modules 150A-150C may possibly receive the same acoustic signal, but would not respond to the signal due to an address mismatch.

FIG. 4 is an illustrative diagram of a fluid sampling tool string environment 260 with a tool string 265 comprised of, for example, a control module 130, two supplemental controllers 160A and 160B, fluid sampling modules 150A-150C, a non-sampling tool 170, and mechanical adapters 140A and 140B. Note: the two supplemental controllers 160A and 160B may be integrated with available adapters or may represent a new class of adapters for a fluid sampling tool string. In FIG. 4, the control module 130 receives electrical signals from the surface interface 108 via the connection line 120 and transmits a downlink acoustic signal via the acoustic channel of the fluid sampling tool string 265. The downlink acoustic signal is received, for example, at least by fluid sampling module 150A and supplemental controller 160 A. Once the supplemental controller 160 A receives the downlink acoustic signal from the control module 130, the supplemental controller 160A transmits a supplemental downlink acoustic signal that is either a new downlink acoustic signal or an amplified version of the received downlink acoustic signal from the control module 130. The supplemental downlink acoustic signal is received, for example, at least by fluid sampling module 15 OB and supplemental controller 160B. Once the supplemental controller 160B receives the supplemental downlink acoustic signal from the supplemental controller 160A, the supplemental controller 160B transmits another supplemental downlink acoustic signal that is either a new supplemental downlink acoustic signal or an amplified version of the received supplemental downlink acoustic signal from the supplemental controller 160A. This process may continue as needed. A similar process can be carried out for uplink acoustic signals until the control module 130 receives all uplink acoustic signals transmitted by fluid sampling modules 150A-150C and/or supplemental controllers 160A and 160B. The surface interface 108 is connected to a computer 105 which enables automated operations, user-based operations, display of collected information, display of fluid sampling options, and/or other features related to the fluid sampling tool string 265.

In some embodiments, downlink acoustic signals transmitted by the control module 130 have higher energy and can propagate further along the acoustic channel provided by the fluid sampling tool string 265 (compared to uplink or downlink acoustic signals transmitted by the fluid sampling modules 150A-150C) depending on how much power is available to the control module 130. Thus, the supplemental controllers 160 A and 160B may not be needed to enhance the range of downlink acoustic signals transmitted by the control module 130. On the other hand, the supplemental controllers 160A and 160B may be needed to enhance the range of uplink acoustic signals transmitted by one or more of the fluid sampling modules 150A-150C due to the limited remote power supply (e.g., battery power) available to the fluid sampling modules 150A- 150C. The size of the adapters associated with the supplemental controllers 160 A and 160B can be selected to provide a sufficient remote power supply and/or sufficient acoustic transducer material to perform the operations described herein.

The non-sampling tool 170 may be positioned at any point along the fluid sampling tool string 265. In some embodiments, the non-sampling tool 170 corresponds to a caliper tool, casing collar location tool, casing corrosion detection tool, or other logging tool suitable for a cased wellbore scenario. Similar to the other components of the fluid sampling tool string 265, the non-sampling tool 170 may send and receive acoustic signals using the acoustic channel provided by the fluid sampling tool string 265. Accordingly, the non-sampling tool 170 may communicate with the surface interface 108 and/or the control module 130 to perform non-sampling operations. In some embodiments, the data collected by the non-sampling tool 170 may be used to direct the timing of fluid sampling operations.

FIG. 5 is a flow block diagram of a method 300 involving a fluid sampling tool string with acoustic signaling. In block 302, the fluid sampling tool string is deployed in a borehole via a connection line that supplies telemetry signals to the tool string. In different embodiments, the connection line may be part of a telemetry channel for acoustic signaling, electrical signaling, optical signaling, or other telemetry options. In block 304, the control module receives a telemetry signal (and possibly electrical power) from the surface interface via the connection line. An example telemetry signal may include instructions to initiate fluid sampling operations. In block 306, the control module transmits a downlink acoustic signal to fluid sampling modules to initiate sampling operations, where the downlink acoustic signal is transmitted based at least in part on the received telemetry signal. In some embodiments, electrical power may be stored in a remote power supply (e.g., a battery), and the downlink acoustic signal is generated at least in part from the power stored in the remote power supply. At block 308, as an optional step may be performed (if any supplemental controllers are present), where supplemental controllers transmit supplemental downlink acoustic signals to fluid sampling modules. At block 310, the fluid sampling modules receive the downlink acoustic signal or supplemental downlink acoustic signal (from either the control module or a supplemental controller) and initiates fluid sampling operations as appropriate. At block 312, as an optional step, the fluid sampling modules transmit uplink acoustic signals to either the supplemental controllers or the control module to report on the current status of the fluid sampling module or on related fluid sampling operations. The control module of the fluid sampling tool string can decode and process any information received from the fluid sampling modules. Additionally or alternatively, the control module may convey information received from fluid sampling modules to a surface interface via an available telemetry channel as described herein. At earth's surface, the information can be processed by a computer 105 to facilitate automated or user-based operations related to the fluid sampling tool string.

Embodiments disclosed herein include:

A: In at least some embodiments, an example method includes deploying a fluid sampling tool string downhole, the fluid sampling tool string including a control module and a plurality of fluid sampling modules, receiving, by the control module, a telemetry signal from a surface interface, transmitting, by the control module, a downlink acoustic signal based at least in part on the received telemetry signal, and initiating a fluid sampling operation, by at least one of the plurality of fluid sampling modules, in response to the downlink acoustic signal.

B: In at least some embodiments, an example system includes a fluid sampling tool string deployed downhole, where the fluid sampling tool string includes a control module and a plurality of fluid sampling modules, and a surface interface in communication with the fluid sampling tool string, where the control module is configured to receive a telemetry signal from the surface interface and to transmit a downlink acoustic signal based at least in part on the telemetry signal, and where at least one of the plurality of fluid sampling modules initiates a fluid sampling operation in response to the downlink acoustic signal.

Each of embodiments A and B may have one or more of the following additional elements in any combination: Element 1 : receiving, by a supplemental controller, the downlink acoustic signal and transmitting a supplemental downlink acoustic signal to one or more of the plurality of fluid sampling modules. Element 2: further comprising transmitting, by one of the plurality of fluid sampling modules, an uplink acoustic signal. Element 3 : further comprising receiving, by a supplemental controller, the uplink acoustic signal, and transmitting a supplemental uplink acoustic signal to the control module or another supplemental controller. Element 4: further comprising transmitting, by the control module, a telemetry signal to a surface interface in response to receiving the uplink acoustic signal or a supplemental uplink acoustic signal. Element 5: further comprising performing an address verification, by one of the plurality of fluid sampling modules, in response to receiving the downlink acoustic signal or a supplemental downlink acoustic signal. Element 6: further comprising transmitting the downlink acoustic signal in response to sensor measurements collected by the fluid sampling tool string. Element 7: further conveying the acoustic signal to one of the plurality of fluid sampling modules via an acoustic channel corresponding to at least two fluid sampling module tool bodies and at least one adapter. Element 8: further comprising assembling the fluid sampling tool string by coupling the plurality of fluid sampling modules together without adapters. Element 9: further comprising assembling the fluid sampling tool string by joining the plurality of fluid sampling modules together with one or more adapters, where at least one of the one or more adapters includes a supplemental controller to convey uplink or downlink acoustic signals. Element 10: where the fluid sampling tool string further comprises a supplemental controller configured to receive the downlink acoustic signal and transmit a supplemental downlink acoustic signal to one or more of the plurality of fluid sampling modules. Element 11 : where the supplemental downlink acoustic signal is a new downlink acoustic signal relative to the received downlink acoustic signal. Element 12: where the supplemental downlink acoustic signal is an amplified version of the received downlink acoustic signal. Element 13: where the supplemental controller is part of an adapter that mechanically couples two of the plurality of fluid sampling modules together. Element 14: where each of the plurality of fluid sampling modules is configured to transmit uplink acoustic signals. Element 15: where each of the plurality of fluid sampling modules is uniquely addressable by the controller. Element 16: where the fluid sampling tool string comprises at least one sensor, and where measurements collected by the at least one sensor are used to direct timing of the downlink acoustic signal. Element 17: where the fluid sampling tool string includes an acoustic channel corresponding to at least two fluid sampling module tool bodies and at least one adapter. Element 18: where the control module is powered by a remote power supply charged by power received from the surface interface. Element 19: where the fluid sampling tool string includes at least one non-sampling tool configured to communicate with the control module via an acoustic channel that includes at least one fluid sampling module tool body.

Numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to embrace all such variations and modifications.