Patent Description:
The present disclosure generally relates to wellbore drilling and, more particularly, to sensing drill bit wear in drilling tools used in the oil and gas industry.

Drilling wellbores in some formations poses challenging conditions, such as a diminished rate of penetration (ROP), drill bit vibrations, drill bit damage, and high pressure and high temperature (HPHT) conditions. The drilling conditions are appraised at the surface by a drilling advisor to determine appropriate drilling parameters, such as revolutions per minute (RPM) of the drill, weight on bit (WOB), and gallons per minute (GPM) of drilling mud pumped during drilling, in light of the perceived drilling conditions.

<CIT> and <CIT> describe wear sensors that are provided on a drill bit or other rotary cutting tool which is for operation in a subterranean borehole and has a plurality of separate cutters protruding from a support structure towards the material to be cut by the tool. The electrically operated sensing means are located at or coupled to a sensing point within a protrusion from the support structure. This sensing point is located within a protrusion such that attrition of at least one cutter to a partially worn state brings the protrusion into abrasive contact with the material being cut and attrition of the protrusion then exposes the sensing point to the material which is being cut by the tool and thereby brings about a detectable change, which may include damage to the sensor at the sensing point, indicative of wear.

<CIT> describes a sensor assembly comprising a sensor to be carried by a movable component movably positionable about a tool body of a downhole tool. The sensor is to take wellsite measurements and the downhole tool is positionable in a wellbore. The sensor assembly further includes electronics positionable in the movable component. The electronics are to electrically connect to the sensor to receive the wellsite measurements from the sensor, and the wellsite measurements are usable to determine wellsite parameters.

<CIT> describes an earth-boring drilling tool comprises a cutting element. The cutting element comprises a substrate, a diamond table, and at least one sensing element formed from a doped diamond material disposed at least partially within the diamond table. A method for determining an at-bit measurement for an earth-boring drill bit comprises receiving an electrical signal generated within a doped diamond material disposed within a diamond table of a cutting element of the earth-boring drill bit, and correlating the electrical signal with at least one parameter during a drilling operation.

<CIT> describes a drill bit that is configured to operate within a wellbore of a hydrocarbon-bearing rock formation. The drill bit includes a drill bit body including at least one leg. The drill bit may include at least one roller cone rotatably mounted on the drill bit body. The roller cone includes a plurality of cutting elements for abrading or crushing rock. The drill bit includes at least one bearing mounted between a surface of the drill bit body and the at least one roller cone to facilitate rotation of the at least one roller cone.

This specification describes downhole drilling systems and methods that can be used to monitor and predict the condition of a drill bit in drilling tools during wellbore drilling. The drill bit is disposed at the end of the drilling system to drill the downhole formation. This drill bit includes a body, two or more blades, and a sensor module embedded in the drill bit. In some examples, the sensor module is embedded into the body of the drill bit. The sensor module includes sensors, instrumentation and signal processing circuits, batteries, insulated conductors, receivers, transmitters, and data storing and processing devices. During a drilling operation, the sensor module measures the electrical or field properties (e.g., acoustic and capacitive properties)that are used to monitor and evaluate the condition of the drill bit.

The drill bit with an onboard sensor module enables virtual drill bit grading (i.e., assessment of drill bit condition) and improved drilling automation. The data from the sensors can be transferred to the data processing system to improve and automate the drilling operation. The onboard sensor module can measure and predict condition of the drill bit. This allows the user to have more confidence when correlating damage reduction to specific drill bit features and enables continuous process improvement.

A method suitable for drilling a wellbore is defined in claim <NUM>.

Embodiments of the method for drilling a wellbore can include one or more of the following features.

In some embodiments, the method includes correlating rate of penetration with drill bit dimensions. In some cases, the method includes calculating lost time associated with reductions in drill bit dimensions. In some cases, the method includes comparing the lost time associated with reductions in drill bit dimensions with non-productive time associated with replacing the drill bit. In some cases, the method includes calculating time until drill bit replacement is required based on a rate of reduction of drill bit dimensions.

In some embodiments, the method includes updating a drilling plan based on the calculated drill bit dimensions.

In some embodiments, the method includes providing calculated drill bit dimensions as input to a drilling automation algorithm.

A system for drilling wellbores is defined in claim <NUM>.

Embodiments of the system for drilling wellbores can include one or more of the following features.

In some embodiments, the insulated conductors include copper with insulating materials disposed between the copper and a body of the drill bit. In some cases, the two insulated conductors have the same dimensions and extend in parallel from the surface of the drill bit to the sensor.

In some embodiments, the system includes a data processing system operable to control drilling operations, the data processing system in electronic communication with the onboard computer. In some cases, the data processing system is configured to receive sensed electrical resistance, calculated drill bit dimensions, or both from the onboard computer. In some cases, the data processing system includes algorithms to correlate drilling rate of penetration with drill bit dimensions. In some cases, the data processing system includes algorithms to calculate lost time associated with reductions in drill bit dimensions. In some cases, the data processing system includes algorithms to compare the lost time associated with reductions in drill bit dimensions with non-productive time associated with replacing the drill bit. In some cases, the data processing system includes algorithms to calculate time until drill bit replacement is required based on a rate of reduction of drill bit dimensions.

In some embodiments, the onboard computer is a printed circuit board.

In some embodiments, the system includes a battery electrically connected to the onboard computer and the sensor.

The prediction of the drill bit grade or condition is done during drilling while the drill bit is downhole. This approach can be used to adjust the drilling automation algorithms for improved drilling performance based on measured data in real-time and can improve the economics of drilling operations. Drill bit condition affects the invisible lost time (e.g., time lost associated with decreases in the rate of penetration due to increased wear on the drill bit). Wear of the drill bit eventually requires a replacement of the drill bit and causes non-productive time associated with tripping the drill string out of and back into the wellbore for the replacement of the drill bit. Understanding the exact drill bit conditions further reduces cost by reducing the invisible lost time and the non-productive time that constitute a significant portion of the overall drilling costs. For example, the ability to accurately predict the drill bit grade can guide decisions on when it is time to trip the drill bit and replace it instead of continuing to drill with a damaged tool. Knowing the exact bit conditions can improve the ROP, extend the drill bit life, guide drilling practices, improve trip plans, enhance drill bit design, and automate drilling operations.

The details of one or more embodiments of these systems and methods are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of these systems and methods will be apparent from the description and drawings, and from the claims.

This specification describes downhole drilling systems and methods that can be used to monitor and predict the condition of a drill bit in drilling tools during wellbore drilling. The drill bit is disposed at the end of the drilling system to drill the downhole formation. This drill bit includes a body, two or more blades, and a sensor module that is embedded into the drill bit blade. In some examples, the sensor module is embedded into the body of the drill bit. The sensor module includes sensors, instrumentation and signal processing circuits, batteries, insulated conductors, receivers, transmitters, and data storing and processing devices. During a drilling operation, the sensor module measures the electrical or field properties (e.g., acoustic and capacitive properties) that are used to monitor and evaluate the condition of the drill bit.

<FIG> is a schematic view of a drilling system <NUM> including a drill string <NUM> drilling a wellbore <NUM>. The drilling system <NUM> includes a derrick <NUM> that supports the drill string <NUM> within the wellbore <NUM>. The drill string <NUM> includes drill pipe <NUM> and a drill bit <NUM>. The drill bit <NUM> is positioned at the downhole end of the drill string <NUM> and includes a sensor module <NUM>. The sensor module <NUM> is embedded in the drill bit <NUM> and is configured to monitor and predict the wear of the drill bit <NUM>.

<FIG> is a schematic view of an example of the drill bit <NUM> with the sensor module <NUM>. The drill bit <NUM> includes a plurality of blades <NUM>, a body <NUM>, and the sensor module <NUM>. The blades <NUM> are polycrystalline diamond compact (PDC) drill bit blades. However, some drill bits implementing the condition sensing approach described in this specification have other types of blades and blades formed from other materials. For example, some drill bits use blades inserts as well as tungsten carbide blades and boron nitride blades. The PDC drill bit blades operate to cut into a subsurface formation to form a wellbore.

In the drill bit <NUM>, the sensor module <NUM> is embedded in the drill bit <NUM>. The sensor module <NUM> includes an electrical resistance sensor <NUM>, two insulated conductors 204a, 204b, onboard computer <NUM> (for example, a printed circuit board) connected to the electrical resistance sensor <NUM>, and a battery <NUM> to power the onboard computer <NUM> and the electrical resistance sensor <NUM>. The electrical resistance sensor <NUM>, the onboard computer <NUM>, and the battery <NUM> are embedded within the body <NUM> of the drill bit <NUM>. The insulated conductors extend from the electrical resistance sensor <NUM> through one of the blades <NUM> of the drill bit <NUM>. For a steel drill bit bodies, the cavity receiving the electrical resistance sensor <NUM>, the onboard computer <NUM>, and the battery <NUM> can be formed during machining and these components subsequently installed. For matrix drill bit bodies, the electrical resistance sensor <NUM>, the onboard computer <NUM>, and the battery <NUM> can incorporated during 3D printing or additive manufacturing processes used to form the drill bit bodies.

The two insulated conductors 204a, 204b extend in parallel from the electrical resistance sensor <NUM> to a surface of the drill bit <NUM>. The two insulated conductors 204a, 204b have equal dimensions. The body of the two insulated conductors 204a, 204b includes copper material or other conductive metal material. Insulating materials (e.g., fiberglass, cellulose, mineral wool, natural fibers, polystyrene, polyisocyanurate, polyurethane, perlite, and combinations thereof) encapsulate the body of the conductors. The insulating layer of the conductors 204a, 204b is placed between the conductive material of the insulated conductor and the blades <NUM> and body <NUM> of the drill bit <NUM>.

The electrical resistance sensor <NUM> is a piezoresistive sensor. The electrical resistance sensor <NUM> measures the resistance of a circuit formed by (<NUM>) one of the insulated conductors 204a, 204b, (<NUM>) the portion of the blade <NUM> between the insulated conductors 204a, 204b, and (<NUM>) the other of the insulated conductors 204a, 204b. As the blades <NUM> of the drill bit <NUM> wear away during use, the insulated conductors 204a, 204b also wear away shortening their length. The shortening of the insulated conductors 204a, 204b reduces the electrical resistance measured by the electrical resistance sensor <NUM>. Some drill bits use other types of sensors (e.g., an impedance sensor, a resistivity sensor, or a capacitance sensor) to measure the electrical resistance.

During a drilling operation (for example, while the drill bit <NUM> is drilling into a formation), the electrical resistance sensor <NUM> senses a change in electrical resistance across the conductors 204a, 204b, as the length of the conductors decreases. The electrical resistance sensor <NUM> then transmits the resistance data to the onboard computer <NUM>. The onboard computer <NUM> includes a data processing system that calculates drill bit wear based the resistance data and transmits the sensed electrical resistance and the calculated drill bit dimensions uphole to a surface data processing system <NUM> controlling drilling operations. The connection between the onboard computer <NUM> and the surface data processing system <NUM> may be a wired connection, a wireless connection, or both. In some cases, the onboard computer <NUM> transmits the sensed electrical resistance or the calculated drill bit dimensions rather than both uphole to a surface data processing system controlling drilling operations.

The surface data processing system <NUM> uses the received sensor data and executes algorithms to determine and control the drilling operations. In some implementations, the surface data processing system is configured to receive sensor data from the onboard computer <NUM> and calculate drill bit dimensions. In some implementations, the surface data processing system is configured to correlate a drilling rate of penetration with the calculated drill bit dimensions. In these implementations, the surface data processing system can calculate lost time associated with reductions in drill bit dimensions and compare the lost time associated with reductions in drill bit dimensions with non-productive time associated with replacing the drill bit. This approach enables the surface data processing system <NUM> to predict the time until drill bit replacement is required based on a rate of reduction of the drill bit dimensions. Based on the received data and the calculated parameters, modifications to the drilling parameters can be implemented to increase the life of the drill bit or to improve the rate of penetration. Additionally, a determination can be made to trip out the drill bit and replace it with a new one can be based on the predicted end-of-life of the drill bit.

<FIG> is a chart showing an example of the relationship <NUM> between an electrical resistance <NUM> and a drill bit wear <NUM>. The chart shows the relationship between drill bit gauge and the resistance sensed by sensor <NUM>. When the drill bit is at full gauge (e.g., no wear) as shown on axis <NUM>, the electrical resistance of the circuit formed by (<NUM>) one of the insulated conductors 204a, 204b, (<NUM>) the portion of the blade <NUM> between the insulated conductors 204a, 204b, and (<NUM>) the other of the insulated conductors 204a, 204b is at its highest (R1). At full gauge (i.e., before use induced wear), the insulated conductors 204a, 204b are at their full length and the electrical charge travels its longest distance. As the drill bit wears down (i.e., gauge decreases), the length of the conductors also decreases. For example, as the gauge of the drill decreases from full gauge to <NUM> (<NUM> inch under gauge), the resistance decreases from R1 to R2. The relationship between gauge and resistance for a particular configuration of drill bit and associated sensors is determined empirically in a laboratory setting.

<FIG> is a flowchart of a method <NUM> for utilizing the change in resistance data sensed by the sensor <NUM> to control one or more parameters of a drilling operation. During drilling operations, the change in electrical resistance across the insulated conductors is sensed by a sensor (<NUM>). The real-time data from the sensor is transmitted to the onboard computer. The onboard computer processes the received data using the data processing system and calculates drill bit dimensions based on the real-time change in resistance data received from the sensor (<NUM>). The measured data, the calculated parameters or both are transmitted from the onboard computer to a surface system that controls the drilling operations (<NUM>). The surface system can correlate the rate of penetration with the drill bit dimensions, calculate lost time associated with reductions in drill bit dimensions, compare the lost time associated with reductions in drill bit dimensions with non-productive time associated with replacing the drill bit, and/or calculate time until drill bit replacement is required based on a rate of reduction of drill bit dimensions. For example, the surface system updates a drilling plan based on the calculated drill bit dimensions or provides calculated drill bit dimensions as an input to a drilling automation algorithm.

<FIG> is a block diagram of an example computer system <NUM> used to provide computational functionalities associated with described algorithms, methods, functions, processes, flows, and procedures described in the present disclosure, according to some implementations of the present disclosure. The illustrated computer <NUM> is intended to encompass any computing device such as a server, a desktop computer, a laptop/notebook computer, a wireless data port, a smartphone, a personal data assistant (PDA), a tablet computing device, or one or more processors within these devices, including physical instances, virtual instances, or both. The computer <NUM> can include input devices such as keypads, keyboards, and touch screens that can accept user information. Also, the computer <NUM> can include output devices that can convey information associated with the operation of the computer <NUM>. The information can include digital data, visual data, audio information, or a combination of information. The information can be presented in a graphical user interface (UI) (or GUI).

At a high level, the computer <NUM> is an electronic computing device operable to receive, transmit, process, store, and manage data and information associated with the described subject matter. According to some implementations, the computer <NUM> can also include, or be communicably coupled with, an application server, an email server, a web server, a caching server, a streaming data server, or a combination of servers.

The computer <NUM> can receive requests over network <NUM> from a client application (for example, executing on another computer <NUM>). The computer <NUM> can respond to the received requests by processing the received requests using software applications. Requests can also be sent to the computer <NUM> from internal users (for example, from a command console), external (or third) parties, automated applications, entities, individuals, systems, and computers. Each of the components of the computer <NUM> can communicate using a system bus <NUM>. In some implementations, any or all of the components of the computer <NUM>, including hardware or software components, can interface with each other or the interface <NUM> (or a combination of both), over the system bus <NUM>. Interfaces can use an application programming interface (API) <NUM>, a service layer <NUM>, or a combination of the API <NUM> and service layer <NUM>. The API <NUM> can include specifications for routines, data structures, and object classes. The API <NUM> can be either computer-language independent or dependent. The API <NUM> can refer to a complete interface, a single function, or a set of APIs.

The service layer <NUM> can provide software services to the computer <NUM> and other components (whether illustrated or not) that are communicably coupled to the computer <NUM>. The functionality of the computer <NUM> can be accessible for all service consumers using this service layer. Software services, such as those provided by the service layer <NUM>, can provide reusable, defined functionalities through a defined interface. For example, the interface can be software written in JAVA, C++, or a language providing data in extensible markup language (XML) format. While illustrated as an integrated component of the computer <NUM>, in alternative implementations, the API <NUM> or the service layer <NUM> can be stand-alone components in relation to other components of the computer <NUM> and other components communicably coupled to the computer <NUM>. Moreover, any or all parts of the API <NUM> or the service layer <NUM> can be implemented as child or sub-modules of another software module, enterprise application, or hardware module without departing from the scope of the present disclosure.

The computer <NUM> includes an interface <NUM>. Although illustrated as a single interface <NUM> in <FIG>, two or more interfaces <NUM> can be used according to particular needs, desires, or particular implementations of the computer <NUM> and the described functionality. The interface <NUM> can be used by the computer <NUM> for communicating with other systems that are connected to the network <NUM> (whether illustrated or not) in a distributed environment. Generally, the interface <NUM> can include, or be implemented using, logic encoded in software or hardware (or a combination of software and hardware) operable to communicate with the network <NUM>. More specifically, the interface <NUM> can include software supporting one or more communication protocols associated with communications. As such, the network <NUM> or the interface's hardware can be operable to communicate physical signals within and outside of the illustrated computer <NUM>.

The computer <NUM> also includes a database <NUM> that can hold data for the computer <NUM> and other components connected to the network <NUM> (whether illustrated or not). For example, database <NUM> can be an in-memory, conventional, or a database storing data consistent with the present disclosure. In some implementations, database <NUM> can be a combination of two or more different database types (for example, hybrid in-memory and conventional databases) according to particular needs, desires, or particular implementations of the computer <NUM> and the described functionality. Although illustrated as a single database <NUM> in <FIG>, two or more databases (of the same, different, or combination of types) can be used according to particular needs, desires, or particular implementations of the computer <NUM> and the described functionality. While database <NUM> is illustrated as an internal component of the computer <NUM>, in alternative implementations, database <NUM> can be external to the computer <NUM>.

The computer <NUM> also includes a memory <NUM> that can hold data for the computer <NUM> or a combination of components connected to the network <NUM> (whether illustrated or not). Memory <NUM> can store any data consistent with the present disclosure. In some implementations, memory <NUM> can be a combination of two or more different types of memory (for example, a combination of semiconductor and magnetic storage) according to particular needs, desires, or particular implementations of the computer <NUM> and the described functionality. Although illustrated as a single memory <NUM> in <FIG>, two or more memories <NUM> (of the same, different, or combination of types) can be used according to particular needs, desires, or particular implementations of the computer <NUM> and the described functionality. While memory <NUM> is illustrated as an internal component of the computer <NUM>, in alternative implementations, memory <NUM> can be external to the computer <NUM>.

There can be any number of computers <NUM> associated with, or external to, a computer system containing computer <NUM>, with each computer <NUM> communicating over network <NUM>. Further, the terms "client," "user," and other appropriate terminology can be used interchangeably, as appropriate, without departing from the scope of the present disclosure. Moreover, the present disclosure contemplates that many users can use one computer <NUM> and one user can use multiple computers <NUM>.

Implementations of the subject matter and the functional operations described in this specification can be implemented in digital electronic circuitry, intangibly embodied computer software or firmware, in computer hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them. Software implementations of the described subject matter can be implemented as one or more computer programs. Each computer program can include one or more modules of computer program instructions encoded on a tangible, non-transitory, computer-readable computer-storage medium for execution by, or to control the operation of, data processing apparatus. Alternatively, or additionally, the program instructions can be encoded in/on an artificially-generated propagated signal. The example, the signal can be a machine-generated electrical, optical, or electromagnetic signal that is generated to encode information for transmission to suitable receiver apparatus for execution by a data processing apparatus. The computer-storage medium can be a machine-readable storage device, a machine-readable storage substrate, a random or serial access memory device, or a combination of computer-storage mediums.

The terms "data processing apparatus," "computer," and "electronic computer device" (or equivalent as understood by one of ordinary skill in the art) refer to data processing hardware. For example, a data processing apparatus can encompass all kinds of apparatus, devices, and machines for processing data, including by way of example, a programmable processor, a computer, or multiple processors or computers. The apparatus can also include special purpose logic circuitry including, for example, a central processing unit (CPU), a field programmable gate array (FPGA), or an application specific integrated circuit (ASIC). In some implementations, the data processing apparatus or special purpose logic circuitry (or a combination of the data processing apparatus or special purpose logic circuitry) can be hardware- or software-based (or a combination of both hardware- and software-based). The apparatus can optionally include code that creates an execution environment for computer programs, for example, code that constitutes processor firmware, a protocol stack, a database management system, an operating system, or a combination of execution environments. The present disclosure contemplates the use of data processing apparatuses with or without conventional operating systems, for example LINUX, UNIX, WINDOWS, MAC OS, ANDROID, or IOS.

A computer program, which can also be referred to or described as a program, software, a software application, a module, a software module, a script, or code, can be written in any form of programming language. Programming languages can include, for example, compiled languages, interpreted languages, declarative languages, or procedural languages. Programs can be deployed in any form, including as stand-alone programs, modules, components, subroutines, or units for use in a computing environment. A program can be stored in a portion of a file that holds other programs or data, for example, one or more scripts stored in a markup language document, in a single file dedicated to the program in question, or in multiple coordinated files storing one or more modules, sub programs, or portions of code. A computer program can be deployed for execution on one computer or on multiple computers that are located, for example, at one site or distributed across multiple sites that are interconnected by a communication network. While portions of the programs illustrated in the various figures may be shown as individual modules that implement the various features and functionality through various objects, methods, or processes, the programs can instead include a number of sub-modules, third-party services, components, and libraries. Conversely, the features and functionality of various components can be combined into single components as appropriate. Thresholds used to make computational determinations can be statically, dynamically, or both statically and dynamically determined.

Computers suitable for the execution of a computer program can be based on one or more of general and special purpose microprocessors and other kinds of CPUs. The elements of a computer are a CPU for performing or executing instructions and one or more memory devices for storing instructions and data. Generally, a CPU can receive instructions and data from (and write data to) a memory. A computer can also include, or be operatively coupled to, one or more mass storage devices for storing data. In some implementations, a computer can receive data from, and transfer data to, the mass storage devices including, for example, magnetic, magneto optical disks, or optical disks. Moreover, a computer can be embedded in another device, for example, a mobile telephone, a personal digital assistant (PDA), a mobile audio or video player, a game console, a global positioning system (GPS) receiver, or a portable storage device such as a universal serial bus (USB) flash drive.

Computer readable media (transitory or non-transitory, as appropriate) suitable for storing computer program instructions and data can include all forms of permanent/non-permanent and volatile/non-volatile memory, media, and memory devices. Computer readable media can include, for example, semiconductor memory devices such as random access memory (RAM), read only memory (ROM), phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), and flash memory devices. Computer readable media can also include, for example, magnetic devices such as tape, cartridges, cassettes, and internal/removable disks. Computer readable media can also include magneto optical disks and optical memory devices and technologies including, for example, digital video disc (DVD), CD ROM, DVD+/-R, DVD-RAM, DVD-ROM, HD-DVD, and BLURAY. The memory can store various objects or data, including caches, classes, frameworks, applications, modules, backup data, jobs, web pages, web page templates, data structures, database tables, repositories, and dynamic information. Types of objects and data stored in memory can include parameters, variables, algorithms, instructions, rules, constraints, and references. Additionally, the memory can include logs, policies, security or access data, and reporting files.

Implementations of the subject matter described in the present disclosure can be implemented on a computer having a display device for providing interaction with a user, including displaying information to (and receiving input from) the user. Types of display devices can include, for example, a cathode ray tube (CRT), a liquid crystal display (LCD), a light-emitting diode (LED), and a plasma monitor. Display devices can include a keyboard and pointing devices including, for example, a mouse, a trackball, or a trackpad. User input can also be provided to the computer through the use of a touchscreen, such as a tablet computer surface with pressure sensitivity or a multi-touch screen using capacitive or electric sensing. Other kinds of devices can be used to provide for interaction with a user, including to receive user feedback, for example, sensory feedback including visual feedback, auditory feedback, or tactile feedback. Input from the user can be received in the form of acoustic, speech, or tactile input. In addition, a computer can interact with a user by sending documents to, and receiving documents from, a device that is used by the user. For example, the computer can send web pages to a web browser on a user's client device in response to requests received from the web browser.

The term "graphical user interface," or "GUI," can be used in the singular or the plural to describe one or more graphical user interfaces and each of the displays of a particular graphical user interface. Therefore, a GUI can represent any graphical user interface, including, but not limited to, a web browser, a touch screen, or a command line interface (CLI) that processes information and efficiently presents the information results to the user. In general, a GUI can include a plurality of user interface (UI) elements, some or all associated with a web browser, such as interactive fields, pull-down lists, and buttons. These and other UI elements can be related to or represent the functions of the web browser.

Implementations of the subject matter described in this specification can be implemented in a computing system that includes a back end component, for example, as a data server, or that includes a middleware component, for example, an application server. Moreover, the computing system can include a front-end component, for example, a client computer having one or both of a graphical user interface or a Web browser through which a user can interact with the computer. The components of the system can be interconnected by any form or medium of wireline or wireless digital data communication (or a combination of data communication) in a communication network. Examples of communication networks include a local area network (LAN), a radio access network (RAN), a metropolitan area network (MAN), a wide area network (WAN), Worldwide Interoperability for Microwave Access (WIMAX), a wireless local area network (WLAN) (for example, using <NUM> a/b/g/n or <NUM> or a combination of protocols), all or a portion of the Internet, or any other communication system or systems at one or more locations (or a combination of communication networks). The network can communicate with, for example, Internet Protocol (IP) packets, frame relay frames, asynchronous transfer mode (ATM) cells, voice, video, data, or a combination of communication types between network addresses.

Cluster file systems can be any file system type accessible from multiple servers for read and update. Locking or consistency tracking may not be necessary since the locking of exchange file system can be done at application layer. Furthermore, Unicode data files can be different from non-Unicode data files.

While this specification contains many specific implementation details, these should not be construed as limitations on the scope of what may be claimed, but rather as descriptions of features that may be specific to particular implementations. Certain features that are described in this specification in the context of separate implementations can also be implemented, in combination, in a single implementation. Conversely, various features that are described in the context of a single implementation can also be implemented in multiple implementations, separately, or in any suitable sub-combination. Moreover, although previously described features may be described as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can, in some cases, be excised from the combination, and the claimed combination may be directed to a sub-combination or variation of a sub-combination.

Claim 1:
A method suitable for drilling a wellbore, the method comprising:
measuring electrical resistance of a circuit formed by
i) a first insulated conductor (<NUM>) extending from an outer surface of a blade (<NUM>) of a drill bit (<NUM>) to a sensor inside the drill bit,
ii) a portion of the blade (<NUM>), and
iii) a second insulated conductor (<NUM>) extending from the outer surface of the blade (<NUM>) of the drill bit (<NUM>) to the sensor inside the drill bit, wherein the portion of the blade (<NUM>) is between the first insulated conductor and the second insulated conductor (<NUM>);
calculating drill bit wear based on the measured electrical resistance; and
transmitting the measured electrical resistance, the calculated drill bit wear, or both uphole to a system for controlling drilling operations.