Patent Description:
Exploration and production of hydrocarbons generally requires the use of various tools that are lowered into a borehole, such as drilling assemblies, measurement tools, and production devices (e.g., fracturing tools). Electronic components may be disposed downhole for various purposes, such as control of downhole tools, communication with the surface, and storage and analysis of data. Traditional printed circuit boards are one such type of electronic components. A printed circuit board (PCB) is a plate or board comprising a substrate supporting different elements that make up an electrical circuit that contains the electrical interconnections between them. The substrate is typically made from epoxy resin. As another example, a multi-chip module (MCM) is an electronic assembly with a number of conductor terminals or "pins" where multiple integrated circuits (ICs or "chips"), semiconductor dies and/or other discrete components are integrated, usually onto a unifying substrate, so that in use it is treated as if it were a single component. Other terms, such as "hybrid" or "hybrid integrated circuit", also refer to MCMs.

The size and cost of making PCB's is one factor that inhibits the efficient use of such electronics in downhole tools. In aspects, the present disclosure addresses the need for enhanced, more compact, and robust electronic components for downhole applications. <CIT> is concerned with a hydrocarbon well performance monitoring system. <CIT> is concerned with a strain gage. <CIT> is concerned with a pressure sensor.

According to an aspect, there is provided an apparatus as claimed in claim <NUM>. In one embodiment, the sensing element is connected to the transducing element without any flexible connection. In one embodiment, the active electronic component is connected to the transducing element without any flexible connection.

According to an aspect, there is provided a method as claimed in claim <NUM>.

Examples of certain features of the disclosure have been summarized rather broadly in order that the detailed description thereof that follows may be better understood and in order that the contributions they represent to the art may be appreciated.

For a detailed understanding of the present disclosure, reference should be made to the following detailed description of the embodiments, taken in conjunction with the accompanying drawings, in which like elements have been given like numerals, wherein:.

In aspects, the present application provides devices that can minimize the space needed for downhole electronics, such as sensors and related electronics. Electronics packages according to some embodiments do not use a PCB or ceramic mounting structure or wiring. The tracks connecting the sensor elements and its electronic or optic circuitry may be produced in a few or even only one manufacturing step by depositing one or more layers on a substrate. To better understand the teachings of the present disclosure, there is described below a drilling system in which devices according to the present disclosure may be used.

Referring now to <FIG>, there is shown one illustrative embodiment of a drilling system <NUM> utilizing a borehole string <NUM> that may include a bottomhole assembly (BHA) <NUM> for directionally drilling a borehole <NUM>. While a land-based rig is shown, these concepts and the methods are equally applicable to offshore drilling systems. The borehole string <NUM> may be suspended from a rig <NUM> and may include jointed tubulars or coiled tubing. In one configuration, the BHA <NUM> may include downhole tools such as a drill bit <NUM>, a sensor sub <NUM>, a power and/or communication module such as a bidirectional communication and power module (BCPM) <NUM>, a formation evaluation (FE) sub <NUM>, and rotary power devices such as drilling motors <NUM>. The sensor sub <NUM> may include sensors for measuring near-bit direction (e.g., BHA azimuth and inclination, BHA coordinates, etc.) and sensors and tools for making rotary directional surveys. The formation evaluation (FE) sub <NUM> may include sensors to measure properties of the formation, such as nuclear tools, resistivity tools, acoustic tools, NMR tools. The borehole string <NUM> may further include sensors to measure the dynamic properties of the drilling process such as weight, torque, rate of penetration, rotational velocity, vibration, acceleration, force, strain, bending and the like that are useful to monitor and/or control the drilling process. The system may also include information processing devices such as a surface controller <NUM> and / or a downhole controller <NUM>. Communication between the surface and the BHA <NUM> may use uplinks and / or downlinks that may be generated by a mud-driven alternator, a mud pulser, an electromagnetic transmitter, an acoustic transmitter and /or conveyed via the mud, hard wires (e.g., electrical conductors, fiber optics), the formation, the borehole, or the borehole string <NUM>. The uplinks and / or downlinks may comprise pressure pulses, electric signals, acoustic signals, or electromagnetic signals or a combination thereof. One or more electronics packages may be used within the BHA <NUM> or other component of the borehole string <NUM> to provide for data storage and processing, communication and/or control functions.

Referring to <FIG>, there is shown one non-limiting embodiment of an electronics package <NUM> that may be used with the drilling system <NUM> of <FIG>. According to the invention, the package <NUM> includes a transducing substrate <NUM> also known as a transducer that is configured to transduce one or more of a strain, a bending, a force, a torque, a pressure, a temperature, a dilatation, and / or a contraction into one or more signals such as an electric signal (e.g., a voltage or a current), an optical signal, a displacement, and / or a dimension (e.g. a length, an area, a volume, or a shape). The package <NUM> further includes one or more sensors or sensing elements <NUM> that are configured to sense the transduced property and to generate analog or digital signals in response to the sensed transduced property, pads <NUM> or tracks <NUM>, and one or more electronic components, e.g. passive components <NUM> or active components <NUM>, that are configured to communicate with the sensing elements <NUM> via at least one of the tracks <NUM>.

As used herein, a transducer or transducing substrate or transducing element is a device that converts a first property in or to a second property. For example, a transducer or transducing substrate or transducing element is a device that converts one form of energy to another. More particularly, a transducer converts a signal in one form of energy to a signal in another form of energy. For example, a mechanical transducer converts a first mechanical property into a second different mechanical or a non-mechanical property, or vice versa. For example, a resistance strain gauge may convert strain or lengthening into an electric signal, a membrane may convert pressure variations into mechanical movement, a solid plate may convert a force signal, a torque signal, or a bending signal into a displacement, a lengthening, a contraction, a bending, etc. A non-mechanical transducer may convert a first non-mechanical property into a second non-mechanical property. For example, a thermocouple converts a temperature signal into an electric signal, etc..

As used herein, a passive component is a component that does not require an electrical power source in order to perform their intended function; e.g., batteries, resistors, capacitors, inductors, antennas, transformers, etc. Generally, passive components can store or maintain energy in the form of voltage or current, but cannot add energy to a system.

As used herein, an active component is a component that requires an electrical power source in order to modify an electrical input signal and/or generate an electrical output signal (e.g., amplifier, such as a pre-amplifier, analog-to-digital converter, processor, microprocessor, vacuum tubes) and may or may not comprise semiconductors. The power source may be a separate part that has flexible electrical connections to the electronics package <NUM>. In another embodiment, the power source may be fixedly connected to the transducing element <NUM> by rigid connections. In one embodiment, the power source may be connected to the transducing element <NUM> without any flexible connection. Active components often have the ability to electrically control electron flow in a circuit to amplify, convert analog signals to digital signals, correct, average, or otherwise process the signal that is communicated by the sensing element <NUM>. Active devices can also add power to a circuit. It should be noted that a "fixed" connection effectively integrates two or more components into a single unit, which prevents relative motion between the two connected components. This is in contrast to a flexible connection which allows relative movement between the two connected bodies.

In a conventional manner, the pads <NUM> are terminals at which electrical or optical connections can be made and the tracks <NUM> act as electrical or optical carriers between two or more points. Electronic components may be bare die components or packaged components which are included in a housing such as a plastic, elastomer, or metal housing configured to mechanically protect the components, to hydraulically seal the components, to transfer heat from or to the components, and / or to at least partially electrically isolate the components within the housing.

The package <NUM> may be formed by integrating at least one of the sensing element <NUM>, the pads <NUM> and the tracks <NUM> onto the transducing substrate or transducing element <NUM> by the process of depositing layers, e.g. thin films of insulating and conducting materials. Sputtering is a commonly known technology that may be utilized to create layers on the transducing element <NUM>. Elements like tracks, pads, or sensing elements may be created by sputtering if combined with masking or subtractive manufacturing such as etching, grinding or laser irradiation. Alternatively, layers may be also created by 3D printing. In this arrangement, the passive and/or active electronic components <NUM>, <NUM> as well as a power source may be fixedly connected by one or more of adhesive attachment, by welding, by soldering, by bonding, or by any type of mechanical fixture such as screws, nuts, clamps, etc..

In one arrangement, the <FIG> embodiment may use a "coin" or disk shaped metallic substrate for the transducing substrate or transducing element <NUM>. A sensing element <NUM>, for example, a strain gauge sensor may be positioned over a thinned down section of the transducing substrate <NUM>. Using a metallic substrate <NUM> allows the connection of the transducing substrate <NUM> to the drilling system <NUM> of <FIG> close enough so that the strain sensed by the strain gauge corresponds to the strain of the drilling system <NUM> of <FIG>. To ensure the close connection of the transducing element <NUM> to the drilling system <NUM> of <FIG>, the transducing element <NUM> needs have a strong enough physical connection so that the metallic transducing substrate <NUM> can withstand the vibrations without breaking. For example, a strain gauge sensor <NUM> may be a sputtered sensor that is connected to sputtered pads <NUM>. As a further example, the strain gauge sensor <NUM> may utilize a bridge configuration to sense the deformation of the transducing substrate <NUM>. The electronic component <NUM> may be a pre-amplifier along with a temperature sensor (not shown) and may be arranged around the central sensing structure and attached by soldering directly onto sputtered pads <NUM>. The temperature sensor may be utilized to correct for temperature effects of the transducing substrate <NUM> and/or the strain gauge sensor <NUM>.

While the foregoing is discussed with respect to a strain sensing element, it should be understood that other sensors are also possible within the scope of this disclosure. For instance, the sensor <NUM> may also comprise an inertia sensing element. For example, the sensor <NUM> may comprise an accelerometer or a gyrometer. Other sensors may include a temperature sensor, an acoustic sensor such as an acoustic wave sensor, a dimension sensor such as a displacement sensor, a length sensor, a dilatation, a contraction sensor, a bending sensor, a force sensor, a torque sensor, and a pressure sensor. Accordingly, the transducing substrate <NUM> may be selected to transduce the signal in the first form of energy to the corresponding second form of energy that the sensor <NUM> is configured to sense.

Referring to <FIG>, there is another non-limiting embodiment of a substrate <NUM> that is suitable for a package configured to estimate torque and / or axial loadings. The transducing element or substrate <NUM> may be formed as a disk having an upper surface <NUM> and a lower surface <NUM>. In some embodiments, a cavity <NUM> may be formed on the lower surface <NUM> in order to make the substrate <NUM> more responsive to flexure. In particular, a wall defining the cavity <NUM> may be thinned to form a membrane <NUM> on which the sensing element <NUM> may be formed. Generally, for applications to estimate physical loadings, the substrate <NUM> should be sufficiently elastically deformable to react in a predetermined way as adjacent structures move, bend, stretch, or twist in response to applied loadings. Thus, the sensor <NUM> deposited (e.g. sputtered) or otherwise fixedly connected to the substrate <NUM> can detect and generate signals representative of such physical deformations. The substrate <NUM> may be formed of metals, non-metals, ceramics, composites, or any other suitable materials or combination of materials. Fixedly connecting the sensor <NUM> to the substrate <NUM> enables the electronics package to be provided as an integral assembly that requires minimized space. In one embodiment, the sensor <NUM> is fixedly connected to the substrate <NUM> without any flexible connection. The substrate may be part of one of the downhole tools that are discussed above with respect to <FIG>.

Referring to <FIG>, there is schematically shown one arrangement for forming an integrated electronics layer for the package <NUM>. In this embodiment, the package <NUM> includes a plurality of layers <NUM> over the transducing element or transducer substrate <NUM>. The layers <NUM> may include one or more electrically insulating layers <NUM>, one or more electrically conductive layers <NUM>, and one or more protection layers <NUM> formed using known thin-film deposition processes such as sputtering. It should be noted that the sensing element <NUM>, pads <NUM>, and tracks <NUM> may be structurally integrated and formed effectively in separate processes or within the same structuring process.

It should be understood that the teachings of the present disclosure may be implemented in various configurations. Some non-limiting embodiments are described below with reference to <FIG>. Each of these embodiments use a transducing element or transducing substrate <NUM> on which the pads <NUM> and tracks <NUM> are defined by a layer deposited on the transducing substrate <NUM> as discussed above. These embodiments might be used, for example, as a sensor for dynamic related properties such as bending, force, torque, weight, and pressure, or as an acoustic sensor such as a hydrophone. However, each figure illustrates a different possible electrical arrangement.

<FIG> illustrates a package <NUM> that does not necessarily incorporate a sensing element. This embodiment uses passive components <NUM>, such as resistive elements <NUM>, active components <NUM>, and other structures with electrical or optical functionality <NUM>.

<FIG> illustrates a package <NUM> that includes a housed component <NUM> that may include an active electronic component (e.g., amplification circuitry), a sensor <NUM>, for example a strain sensor or a piezoelectric crystal, sensing the signal from the transducing substrate <NUM>, and a passive electronic component such as resistive circuitry <NUM> or capacitor <NUM> and an active electronic component such as an amplifier <NUM>. In this embodiment, the connections, e.g., the connections <NUM> for the housed component <NUM>, use adhesives and / or solders. Other embodiments might include welded or sintered connections or any type of wire bond. It should be noted that the amplification circuitry in the housed component <NUM> can be readily located close to the sensor <NUM> that is in close contact to the transducing substrate <NUM> to minimize problems that may occur when weak sensor signals are present.

<FIG> illustrates a package <NUM> that is similar to the <FIG> embodiment, but includes a bare die component <NUM>. In this embodiment, there are a combination of wire bonded connections and adhesive / soldered connections. For example, there may be wire bonded connections <NUM> and adhesive / solder connections <NUM>.

In still another embodiment that is not shown, one or more of a sensor such as a strain sensor, a track, and a pad may be sputtered or otherwise deposited on a metallic substrate to form a sensor module. This sensor module may then be connected to a PCB board or other electronic device using flexible wiring and adhesives / soldering / connectors / clamps or other wire bond techniques.

While the present teachings have been discussed in the context of hydrocarbon producing wells, it should be understood that the present teachings may be applied to geothermal wells, groundwater wells, subsea analysis, etc. Also, any conveyance device, other than a drill string, may be used to convey downhole tools. Exemplary non-limiting conveyance devices include casing pipes, wirelines, wire line sondes, slickline sondes, drop shots, self-propelled tractors etc..

Claim 1:
An apparatus for use in a wellbore, characterized by:
- a transducing substrate (<NUM>) configured to transduce a first property into a second property;
- a sensing element (<NUM>) fixedly connected to the transducing substrate (<NUM>) and configured to generate a signal in response to the second property;
- layers (<NUM>) created on the transducing substrate (<NUM>) by sputtering or 3D printing, the layers (<NUM>) defining at least one track (<NUM>) and including an insulating layer (<NUM>) and a conductive layer (<NUM>); and
- at least one active electronic component (<NUM>) fixedly connected to the transducing substrate (<NUM>) and in communication with the sensing element (<NUM>) via the at least one track (<NUM>).