WO2023187458A1

WO2023187458A1 - Systems and methods for wellbore investigation and log-interpretation via self-propelling wireless robotic wellbore logging tool

Info

Publication number: WO2023187458A1
Application number: PCT/IB2022/054778
Authority: WO
Inventors: Nitin Lahkar; Rishiraj Goswami; Arnab Kumar Barman
Original assignee: Nitin Lahkar; Rishiraj Goswami; Arnab Kumar Barman
Priority date: 2022-03-29
Filing date: 2022-05-22
Publication date: 2023-10-05

Abstract

A method for wellbore investigation and log-interpretation via a self-propelling wireless robotic wellbore logging tool, includes the steps of, transporting the self-propelling wireless robotic wellbore logging tool wirelessly inside a wellbore of any dimension via an autonomous robot; collecting logging data in real-time; storing the logging data in a memory capsule for data exchange facilities to further retrieve onto a processing device; releasing the self-propelling wireless robotic wellbore logging tool to a surface using buoyancy or wellbore pressure for energy efficiency; transferring the logging data collected via the self-propelling wireless robotic wellbore logging tool to a subsurface control station via wellbore fluids using an underwater communication technique; and, analysing the logging data using artificial intelligence for quicker interpretation.

Description

SYSTEMS AND METHODS FOR WELLBORE INVESTIGATION AND LOGINTERPRETATION VIA SELF-PROPELLING WIRELESS ROBOTIC WELLBORE LOGGING TOOL

FIELD OF THE INVENTION

Embodiments of the present invention generally relate to the field of oil well logging and, more particularly, to systems and methods for wellbore investigation and log-interpretation via self-propelling wireless robotic wellbore logging tool.

BACKGROUND OF THE INVENTION

As it is known that underground reservoirs are storehouses of oil which is mainly present in the pores of rocks, however, there is also availability of water and gas. Therefore, to determine or evaluate the part of core spaces filled with oil particularly, logging techniques are used.

Well logging is a technique used for determining the core spaces of rocks filled with oil via a logging device that goes into a borehole, drilled into the soil. In other words, Oil Well Logging” or the practice of making a detailed record (a well log) of the geologic formations penetrated by a borehole is an important practice in the Oil and Gas industry. Such logging devices have sensors for detecting many parameters to detect oil in rocks or other soil characteristics. However, these logging devices cause difficulties from damage during installation of the pumping string and during logging procedures. Therefore, the logging industry has seen many revolutionary changes.

Furthermore, in accordance with one of the conventional prior art literature references, wireline logging has been disclosed wherein the logging tool is lowered down a borehole and records petro physical characteristics, using various sensors. Moreover, wireline damage can also occur from various factors such as drum crush or the wireline is physically unable to support the increased loads in deep logging operation. In addition to this, the drill pipe can get stuck adding to additional wireline tension which further causes wireline failure.

Additionally, in accordance with another prior art disclosure, a conventional method of tractor well logging has been disclosed wherein the logging tool is pushed down the borehole with the use of the wheel section of a tractor. However, such a conventional method of logging requires huge mechanical support and efficient manpower, making the process more time consuming and expensive.

Moreover, other prior art disclosures also exist wherein pipe conveyed logging technique has been disclosed. This method includes the use of a drill pipe to convey the tools to the required logging depth. This system mechanically connects the logging assembly to the end of the drill string, using a specially designed crossover called a down hole wet connector. However, this method needs huge mechanical requirements and is time consuming. Various disclosures on logging technology that have been disclosed herein does not solve all the problems that arise during the logging procedure such as huge efficient manpower and time consuming procedures. In this regard, the technique that requires less manpower, less amount of time and provides high quality log data in difficult wells is the need of the hour. Moreover, a logging technique wherein the logging tool does not get stuck in the borewell and further does not cause any wireline tensions is required in the logging industry.

Therefore, there is a need for a logging technique that can overcome the problems related to the conventional logging technique, including but not limited to, time consuming procedures, huge mechanical requirements and the like. Accessibility and availability of efficient manpower, resources and technology is very time consuming, restricted and often costly at times. So, in this regard, the thought for the solution to this problem has given rise to a revolutionary concept called the “Robotic Logging Technology”. Robotic logging technology promises the advent of successful logging in all kinds of wells and trajectories. It consists of a wireless logging tool controlled from the surface. This eliminates the need for the logging truck to be summoned which in turn saves precious rig time and in turn also reduces bulk mechanical requirements by introduction of robotics and automation in the oil well logging technology.

Accordingly, there remains a need in the art for innovative, novel, efficient solutions for providing wellbore investigation and log-interpretation via self- propelling wireless robotic wellbore logging tool. SUMMARY OF THE INVENTION

In accordance with an embodiment of the present invention, a method for wellbore investigation and log-interpretation via a self-propelling wireless robotic wellbore logging tool, includes the steps of, transporting the self- propelling wireless robotic wellbore logging tool wirelessly inside a wellbore of any dimension via an autonomous robot; collecting logging data in realtime; storing the logging data in a memory capsule for data exchange facilities to further retrieve onto a processing device; releasing the self-propelling wireless robotic wellbore logging tool to a surface using buoyancy or wellbore pressure for energy efficiency; transferring the logging data collected via the self-propelling wireless robotic wellbore logging tool to a subsurface control station via wellbore fluids using an underwater communication technique; and, analysing the logging data using artificial intelligence for quicker interpretation. The embodiments of the present disclosure have several features, no single one of which is solely responsible for their desirable attributes. Without limiting the scope of the present embodiments as expressed by the claims that follow, their more prominent features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled “Detailed Description”, one will understand how the features of the present embodiments provide advantages, which include providing systems and methods for wellbore investigation and preliminary log-interpretation via self-propelling wireless robotic wellbore logging tool.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a general representation of a robotic logging tool, according to an embodiment of the invention;

Fig 2 illustrates the robotic logging tool inside a cased wellbore with packer & tubing (projected perforations for visual understanding only), according to an embodiment of the invention;

Fig 3 illustrates the robotic logging tool inside a cased wellbore (diagrammatic representation), according to an embodiment of the invention; and,

Fig 4 illustrates the robotic logging tool inside an open wellbore (diagrammatic representation), according to an embodiment of the invention.

DESCRIPTION OF THE INVENTION

Various embodiments of the present invention are disclosed herein below, which relate to systems and methods for wellbore investigation and loginterpretation via self-propelling wireless robotic wellbore logging tool.

Generally, the wireline technology consists of a slick-line cable (“the wireline”) that is used for the extraction of petrophysical and geophysical data. Such data can be further utilized for the analysis of subsurface geology and reservoir properties. The conventional technologies make use of a logging truck wherein the wireline is used to lower the logging tools into the wellbore while the logging truck is used to unspool the wireline and deploy the connected tool string at the desired depth. Various specialized tools record the desired formation properties and transmit the real time information using the braided wireline in the form of the electrical impulses. However, there are several problems associated with the current Wireline Logging technology. Along with high manpower requirements, a large amount of non-productive time is spent in conventional operation. Moreover, due to bulky logging trucks and associated mechanisms money and energy are wasted. Furthermore, fishing with wireline logging technology is unpredictable and difficult because both the logging tool and the wireline may get stuck. Additionally, the process needs heavy requirements for equipment, transportation, and manpower, thus, making wireline logging technology expensive.

Furthermore, in conventional logging, the external force (from outside the wellbore) is the only mechanism to fish (pull out the tool) from the stuck point and requires a strong and costly wireline to keep the logging tool stable and in tension. The interpretation too is tedious and time consuming. A typical logging truck is operated by a crew of five members which adds to the manpower costs and the mobilization time of the unit adds to the total downtime of the well.

In accordance with the embodiment of the present invention, a wireless robot(s) which is a uniquely designed array used to wirelessly traverse inside oil and gas bore-wells of any dimension, type, and trajectory. In use, logging data collected via the self-propelling wireless robotic wellbore logging tool is transferred to a subsurface control station via wellbore fluids using underwater communication.

The robot uses various underwater communication techniques to transfer data via the wellbore fluids. These systems are present either standalone or in combinations depending on subsurface conditions and type of wellbore. There are various embodiments of the robot with varying communication systems involving acoustic waves, mud telemetry, laser and/ or light based or could be Infra-red. Depending on surface and subsurface conditions, robots are deployed. Further, the communication link is used to establish high bandwidth communication for data exchange or upload information gathered during the logging as well as receive new parameters for the next operation. The operator central or control station may be located anywhere in the world which may be connected via satellite network via a surface buoy or surface facility near the logging site. This greatly facilitates logging in logistically challenging areas. Subsequently, logging data is analyzed using artificial intelligence for quicker interpretation.

Furthermore, in accordance with an embodiment of the present invention, a wirelessly controlled and/or autonomous robot that is used for collecting real time well-logging data in any trajectory, any depth of well-bore in a swift, unique and with enhanced effectivity, further contains embedded power sources installed inside the self-propelling wireless robotic wellbore logging tool. In use, this power source provides power to the tool. It is energy efficient during operation to ensure long battery lifetime, reduce utility power consumption, and prevent excess heat.

Additionally, in accordance with an embodiment of the present invention, a self- propelling wireless robotic wellbore logging tool comprises a cutter, to push itself out when stuck or fished on sand and wax and propellers. In use, propellers guide the self-propelling wireless robotic wellbore logging tool downhole. Further it comprises wheels to adapt itself to a diameter of the wellbore and a camera dome. In use, the camera dome provides visual data for well inspection and activities related to hydrocarbon well logging. Further, the tool comprises a fishing neck for ease of fishing operations using fishing tools. These fishing tools are used to pull out the logging tool from the wellbore, and comprises a tubular member having a fishing profile disposed within or secured to the inner wall surface of the tubular member, disposed over a portion of the logging tool.

Subsequently, once the logging tool is gripped by the fishing tool, the fishing tool and the logging tool are transported to the surface of the well, thus retrieving the tool from the wellbore. Further, there are various types of fishing tools, run by using different methods such as wireline, slick line or electric line, however, these fishing methods are effective.

Additionally, in accordance with an embodiment of the present invention, a directional module comprising pads, having a claw like structure/magnetic- pads/fins/leg like structures. In use, these claw-like structures are used for directional control wherein the pads push against the wall of the wellbore, for change of direction and suspend itself in any point of the wellbore and, a muleshoe Profile/ Sharp edge, to make its way through the wellbore.

Moreover, in accordance with an embodiment of the present invention, the self- propelling wireless robotic wellbore logging tool is covered by an intelligent sensory skin which is either of an array of sensors or multidirectional fins acting as micro sensors. In use, the intelligent sensory skin is reinforced with high tensile, high strength composite material to withstand extremities of environment including HPHT wells, unconsolidated sands, faults, natural fractures with negligible wear and tear. Furthermore, in accordance with an embodiment of the present invention, the self-propelling wireless robotic wellbore logging tool further comprises a plurality of acoustic/visual sensors. In use, these sensors detect pressure/temperature fluctuations, measured depth (MD), inclination, orientation, azimuth, true vertical depth (TVD), brine salinity contrast downhole and further transmit signals to be received at the surface via electrical wellheads.

Therefore, as may be seen, various embodiments of the present invention as disclosed hereinabove provide significant advantages over prior art, such as, for example, but not limited to, energy efficiency wherein the use of buoyancy consumes less energy in logging as the present technique utilizes fluid pressure to release the tool to the wellbore surface. Further, the wellbore fluid using an underwater communication technique provides much faster data transmission from a deep underwater environment. This is possible via acoustic signals, preferred over electromagnetic waves for underwater data transmission since it can travel in water without much distortion.

In addition, the collected logging data, alongside getting stored into a memory capsule, gets transmitted wirelessly to get a real-time update. Additionally, the present technology uses robots, machine learning and artificial intelligence, to analyze logging. Further, Artificial intelligence, with its accuracy, generates an automated report on specific areas of interest in a human-readable form, which helps interpret data and make decisions quickly. Subsequently, the present invention is more economical as the techniques embedded in a single tool makes the robotic wellbore logging tool all in one functionality tool. As a result, the said robotic wellbore logging tool cuts down the cost of human resources and equipment, making it a cheap and economic logging process.

Moreover, a self-sustainable electric circuit installed on the robotic wellbore logging tool consistently supplies power to the robotic wellbore logging tool. The tool won’t need to rely on the external factor for power supply, which is a huge advantage in cost saving. Additionally, the present technology is environmentally friendly as it eliminates fuel use and reduces the use of heavy vehicles for pulling out the tool from the wellbore, also reducing manpower.

FIG. 1 illustrates a general representation of a robotic tool, according to an embodiment of the invention. As illustrated therein, the element list is as follows:

1 : Cutter system

2: Propeller

3: Fishing neck

4: Wheel

5: Camera dome

6: Robot body containing all logging tools inside covered with intelligent skin.

7: Pads/leg like structures

8: Muleshoe Profile/ Sharp edge

In accordance with an embodiment of the present invention, the invention comprises of various modules. The robot is a single entity or an array of robots placed like carriages in multiple well defined and segregated stages with each stage having some definite functional property. One embodiment may help in the propulsion or locomotion of the system. Another embodiment may be divided into different modules to perform logging of the wellbore. Power subsystem is incorporated.

It can also be stated that one embodiment of the invention relates to the locomotion of the robot through wellbore of any possible trajectory. Well completion maybe of any type-open hole, cased, cased and perforated with tubing, tubingless, liner completion etc. just to name a few. Few embodiments of robot locomotion are mentioned below. These systems are present either standalone or in combinations depending on subsurface conditions and type of wellbore, including, leg-like structures (with and/ or without pads and fins), use of wheels and/ or rollers that can adapt itself to the surface (of wellbore)(element 4,7 of fig 1 ), using track system, and, using Propellers (element 2, fig1 ).

It is understood that invention is not limited to the description of above embodiments. The characteristics and features of the current invention may be deployed in numerous embodiments without differing much from the scope of the invention. Such similar and variant embodiments incorporating modifications, changes, adaptations, are basically within the scope of this robot. The robot can be incorporated with pads or fins for the directional control. The pads push against the wall of the wellbore/casing/tubing and help in the change of direction.

In addition, the invention consists of a communication system as well as a data logging system and its transfer to the subsurface control station. The robot uses various underwater communication techniques to transfer data via the wellbore fluids. Few embodiments of robot communication are mentioned below. These systems are present either standalone or in combinations depending on subsurface conditions and type of wellbore, including, Acoustic waves, Mud telemetry, Laser and/ or light based, and, Infra-red.

There are various embodiments of the robot with varying communication systems and above embodiments are not exhaustive. Depending on surface and sub-surface conditions robot will be deployed. The communication link will be used to establish high bandwidth communication for data exchange or upload information gathered during the logging as well as receive new parameters for the next operation. The operator central or control station may be located anywhere in the world which may be connected via satellite network via a surface buoy or surface facility near the logging site. This greatly facilitates logging in logistically challenging areas.

In use, an autonomous robot or an autonomous vehicle or a drone mounted with robotic manipulator maybe used to release or project the robot from the surface to the wellbore in a certain trajectory. In some circumstances this minimizes system requirements and huge cost and time required to setup or transfer an oil rig and the facility from one place to another.

From the perspective of awareness and intelligent perception, the system will contain various acoustic and visual sensors that help for intelligent perception for enhancement of the navigation and self-awareness and self-monitoring. One embodiment of the invention will contain camera as well as acoustic sensors for providing visual data for well inspection and activities related to hydrocarbon well logging. Its body is covered with a novel intelligent sensory skin which is either of an array of sensors or multidirectional fins that act as micro sensors (depending on wellbore conditions). (element 6, fig 1 ) Moreover, one embodiment of data-logging (well-logging) will store the log data in memory capsule for data exchange facilities which maybe further retrieved onto a computer. It may be also transferred wirelessly to the surface and sent to a storage device or cloud storage device. Various compression techniques may be used to decrease bandwidth requirements before sending the data. Real time onboard analysis of the retrieved log data using artificial intelligence will be performed to aid the geologist or engineer for quicker interpretation of the log data. The logging tools maybe embedded onto the robot or a stage of the robot where the robot can take readings continually or in discrete manner. The invention is designed to acquire the log data which is collected by the conventional wireline logging tools viz. SP, Caliper, Gamma ray, Density, Neutron, Sonic, Resistivity (shallow, medium, deep, MSFL and others), NMR, FMI, PLT and all available forms of logs. One embodiment of the robot contains a novel form of logging probe that gives a scanned image of the formation upto a certain depth of investigation, indicating the geophysical properties of the formation and may help in direct prediction of hydrocarbons. The petrophysical parameters are stored onboard or sent to a control operator on the surface. The interpretation of the features of the logs is done using artificial intelligence and machine learning models.

Further, the multi-modal robot will consist of advanced sensors for collecting basic wellbore data like wellbore temperature, differential pressure, measured depth (MD), inclination, orientation, azimuth, True vertical depth (TVD). One embodiment of the module may take the data and release itself to the surface using buoyancy or wellbore pressure for energy efficiency. Further that also gives an advantage in critical situations when the robot is stuck (fish). Other stages may also be gradually released to the surface as per convenience.

The power required to drive the robot maybe stored in battery packs or wirelessly powered or recharged and storing it in battery packs. The robot may also be recharged from the well bore characteristics like temperature, pressure, etc. Also, a nuclear-powered generator or a novel nuclear cell or such form of clean energy maybe be used for providing power. This helps the intelligent robotic system to be wellbore resident, meaning if deployed once, stays inside for desired time as per requirements in specific conditions, wellbore operations, well test and PLT operations.

Various backup and safety measures are taken to make it a fail-safe system. The ratio of diameter of the robot to the diameter of the wellbore is optimized for reducing wall effects. One of more types of locomotion combined with propeller or non-propeller-based propulsion system is kept ensuring safety. The robot may suspend itself in any point of wellbore with the help of claw like structure as well as magnetic pads. In case it is stuck or fished on sand and wax, it uses a cutting tool and a mechanism to push itself out (Element 8 & Element 2, fig 1 ). A provision is also kept for attaching the fishing tool via a fish neck (Element 3, fig 1 ) to pull it out using external force in critical condition.

The invention can withstand extremities of environment such as. HPHT wells, unconsolidated sands, faults, natural fractures with negligible wear and tear, so that, otherwise possible phenomena viz. biofouling, corrosion, cracking, erosion, etc. are avoided. This is made possible with the special material of construction as well as the hydrodynamically efficient shape. The material is reinforced with high tensile, high strength composite materials, keeping its weight lighter but at the same time highly tolerant to external forces. The material also provides fire proofing for improved safety.

Conditional language used herein, such as, among others, “can,” “could,” “might,” “may,” “e.g.,” and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without author input or prompting, whether these features, elements and/or steps are included or are to be performed in any particular embodiment. The terms "comprising," "including," 'having," and the like are synonymous and are used inclusively, in an open-ended fashion, and do not exclude additional elements, features, acts, operations, and so forth. Also, the term "or" is used in its inclusive sense (and not in its exclusive sense) so that when used, for example, to connect a list of elements, the term "or" means one, some, or all of the elements in the list.

While there has been shown and described the preferred embodiment of the instant invention it is to be appreciated that the invention may be embodied otherwise than is herein specifically shown and described and that, within said embodiment, certain changes may be made in the form and arrangement of the parts without departing from the underlying ideas or principles of this invention as set forth in the Claims appended herewith. Therefore, the appended claims are to be construed to cover all equivalents falling within the true scope and spirit of the invention.

Claims

Claims I / We claim,

1. A method for wellbore investigation and log-interpretation via a self- propelling wireless robotic wellbore logging tool, said method comprising the steps of: transporting said self-propelling wireless robotic wellbore logging tool wirelessly inside a wellbore of any dimension via an autonomous robot; collecting logging data in real-time; storing said logging data in a memory capsule for data exchange facilities to further retrieve onto a processing device; releasing said self-propelling wireless robotic wellbore logging tool to a surface using buoyancy or wellbore pressure for energy efficiency; transferring said logging data collected via said self-propelling wireless robotic wellbore logging tool to a subsurface control station via wellbore fluids using an underwater communication technique; and, analysing said logging data using artificial intelligence for quicker interpretation.

2. The method as claimed in claim 1 , wherein said method further comprises the step of powering said self-propelling wireless robotic wellbore logging tool via a self-sustained electrical circuitry installed inside said self- propelling wireless robotic wellbore logging tool.

3. A system for wellbore investigation and log-interpretation, said system comprising: a self-propelling wireless robotic wellbore logging tool; a cutter, to push itself out when stuck or fished on sand and wax; a plurality of propellers for guiding said self-propelling wireless robotic wellbore logging tool downhole; a fishing neck for ease of fishing operations using a plurality of fishing tools; a plurality of wheels mounted on said self-propelling wireless robotic wellbore logging tool, said plurality of wheels being configured to adapt itself to a diameter of said wellbore; and, a camera dome, for providing visual data for well inspection and activities related to hydrocarbon well logging; characterised in that, said self-propelling wireless robotic wellbore logging tool having a selfcleaning technology using reverse spinning of thrusters based on pre-set anti drag sensor readings, further characterised in that, said self-propelling wireless robotic wellbore logging tool having a different sub-surface, underwater/ under-fluid communication systems and telemetry to transfer log-data via wellbore fluids.

4. The system as claimed in Claim 3, wherein said system further comprises, a directional module comprising a plurality of pads, said directional module being a claw like structure/magnetic-pads/fins/leg like structures, for directional control wherein said plurality of pads push against wall of said wellbore for change of direction and suspend itself in any point of said wellbore; and, a muleshoe Profile/ Sharp edge, to make its way through said wellbore.

5. The system as claimed in claim 4, wherein said system further comprises an intelligent sensory skin which is either of an array of sensors or multidirectional fins act as micro sensors covering said self-propelling wireless robotic wellbore logging tool.

6. The system as claimed in claim 5, wherein said intelligent sensory skin is further reinforced with high tensile, high strength composite material to withstand extremities of environment including HPHT wells, unconsolidated sands, faults, natural fractures with negligible wear and tear.

7. The system as claimed in claim 4, wherein said self-propelling wireless robotic wellbore logging tool is either embedded onto a robot or a stage of a robot to take readings continually.

8. The system as claimed in claim 4, wherein said self-propelling wireless robotic wellbore logging tool further comprises a plurality of acoustic/visual sensors to detect pressure/temperature fluctuations, measured depth (MD), inclination, orientation, azimuth, true vertical depth (TVD), brine salinity contrast downhole and further transmit signals to be received at the surface via electrical wellheads.