None.
Disclosed embodiments relate generally to downhole drilling operations and more particularly to a downhole assembly employing wired drill pipe.
During drilling operations, measurements of downhole conditions taken while drilling can provide valuable information that may be used by a drilling operator to improve efficiency and performance and minimize risk. Such measurements may include measurement while drilling (MWD) and logging while drilling (LWD) measurements to obtain information about the wellbore and the surrounding formations. Along string temperature and pressure measurements (ASM) may also be of value to a drilling operator. Such along string measurements may be utilized, for example, to compute interval densities along the length of the drill string as is disclosed in U.S. Patent Publication 2013/0048380, which is incorporated herein in its entirety.
While MWD, LWD, and ASM are used in downhole drilling operations, there is room for further development. For example, there is room for improved measurements as well as for improved communication between sensors deployed along a portion of the drill string and sensors in the bottom hole assembly (BHA).
A system for drilling a subterranean wellbore includes a bottom hole assembly (BHA) coupled to a downhole end of a drill string. The BHA includes an electronic controller having a processor. The drill string includes downhole and uphole portions with the downhole portion made up of wired drill pipe and the uphole portion made up of non-wired drill pipe. The downhole portion further includes at least one sensor sub having at least one downhole sensor. The wired drill pipe provides an electronic communication link between the sensor and the processor in the bottom hole assembly.
A method for making downhole measurements includes deploying a drilling system in a subterranean wellbore. The drilling system may include a bottom hole assembly coupled to a downhole end of a drill string. The drill string includes downhole and uphole portions, the downhole portion being made up of wired drill pipe and the uphole portion being made up of non-wired drill pipe. A sensor sub including at least one sensor is deployed in the downhole portion of the drill string. A communication channel is established between the downhole sensor and a processor in the BHA using the wired drill pipe. The sensor acquires a measurement and transmits the measurement to the processor in the BHA via the wired drill pipe communication channel. The processor then processes the measurement to compute a parameter of interest which is in turn transmitted to the surface using a non-wired drill pipe communication channel such as mud pulse telemetry.
A method for downlinking data and/or a command from a surface location to a downhole processor includes providing a drilling system such as that described in the preceding paragraph. The command and/or data is transmitted from the surface to the sensor in the downhole portion of the drill string using a non-wired drill pipe communication channel, for example, employing drilling fluid pressure pulses or drill string rotation encoding. The downlinked command and/or data may then be transmitted from the sensor to the processor in the BHA using the wired drill pipe communication channel. In one embodiment, the data and/or command is decoded via a processor located proximate to the sensor. The decoded data and/or command may then be transmitted to the BHA using the wired drill pipe communication channel. In another embodiment, the signal received at the sensor is transmitted to the BHA using the wired drill pipe communication channel and then decoded using the processor in the BHA.
A method for actuating a downhole tool includes deploying a drilling system in a subterranean wellbore. The drilling system may be similar to that described above in that it includes a drill string having downhole and uphole portions, the downhole portion being made up of wired drill pipe and the uphole portion being made up of non-wired drill pipe. An actuatable downhole tool is deployed in the downhole portion. A communication channel is established between the downhole tool and a processor in the BHA using the wired drill pipe. The downhole tool may be actuated by transmitting a command from the processor to the downhole tool via the wired drill pipe.
This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.
For a more complete understanding of the disclosed subject matter, and advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
With further reference to the wired drill pipe in the lower portion 60 of the drill string, it will be understood that such wire drill pipe includes one or more electrically conductive wires deployed in each length of drill pipe. Coupling devices (e.g., inductive couplers) are located at each end of the lengths of pipe so that when the pipes are threadably connected, or otherwise coupled to one another, the wired drill pipe provides a hardwired communication link spanning several lengths of pipe (i.e., across one or more joints).
The lower portion 60 of the drill string 30 may further include one or more wired drill pipe repeater subs 62 and/or sensor subs 64. These subs 62 and 64 may include substantially any suitable measurement while drilling (MWD) and/or logging while drilling (LWD) sensors 66, for example, including accelerometers, magnetometers, internal or annular pressure sensors, temperature sensors, a natural gamma ray sensor, a neutron sensor, a density sensor, an electromagnetic antenna, a resistivity sensor, an ultrasonic sensor, an audio-frequency acoustic sensor, and the like. Such sensors may also be deployed in various MWD and LWD tools (e.g., in measurement tools 80 and 90) in the BHA 50. It will be understood that the disclosed embodiments are not limited to any particular sensor deployments.
The sensor sub 64 (or subs) employing various MWD and/or LWD sensors 66 may have substantially any longitudinal spacing along the lower portion of the drill string 30. For example, the wired drill pipe may include a single sensor sub 64 located at the intermediate location 35 which may be from several hundred to several thousand feet above the drill bit 32, depending on the specific requirements of the drilling operation. The wired drill pipe may also include several sensor subs 64 having an axial spacing along the string in a range, for example, from about 100 to 1000 feet in measured depth. Moreover, the spacing between adjacent sensor subs 64 is not necessarily uniform. For example, a longitudinal spacing between first and second sensor subs is not necessarily equal to the spacing between second and third sensor subs. The disclosed embodiments are not limited in any of these regards.
In the depicted embodiment, the BHA 50 further includes an MWD tool 80 located near the drill bit 32. The MWD tool may include various wellbore surveying sensors 82, for example, including a tri-axial accelerometer set, a tri-axial magnetometer set, and/or one or more gyroscopic sensors. The MWD tool 80 may further include a telemetry device 84 such as a mudflow telemetry device and/or an electromagnetic telemetry device. As is known to those of ordinary skill in the art, a mudflow telemetry device is configured to selectively block or partially block the flow of drilling fluid through the drill string 30 thereby causing pressure changes therein. In other words, the telemetry device 84 may be configured to modulate the pressure in the drilling fluid to transmit data from the BHA 50 to a surface location. Modulated changes in pressure may be detected by a pressure transducer at the surface and processed to reconstruct the transmitted data. Modulation and demodulation of such pressure waves are described in detail in commonly assigned U.S. Pat. No. 5,375,098, which is incorporated by reference herein in its entirety. As is also known to those of ordinary skill in the art, an electromagnetic telemetry device utilizes low frequency electromagnetic waves to communicate with the surface. One example of an electromagnetic telemetry device suitable for two-way communication with the surface is disclosed in commonly assigned U.S. Pat. No. 6,727,827, which is incorporated by reference herein in its entirety.
The BHA 50 may further include an LWD tool 90 located near the drill bit 32. The LWD tool 90 may include substantially any suitable formation evaluation sensors 92 (also referred to as LWD sensors) for measuring various formation properties such as the porosity, the density, the resistivity, and the acoustic velocity of the formation. The formation evaluation sensors 92 may include, for example, a natural gamma ray sensor, a neutron sensor, a density sensor, an electromagnetic antenna, a resistivity sensor, a formation pressure sensor, an annular pressure sensor, a temperature sensor, an ultrasonic sensor, an audio-frequency acoustic sensor, a caliper sensor, and the like. The sensors may also include sensors for measuring the characteristics of the BHA such as strain gauges for measuring various directional strain components in the BHA. The disclosed embodiments are not limited to the use of any particular sensor embodiments or configurations.
It will be understood that the deployment illustrated on
It will be understood that method 100 may be utilized in making substantially any suitable downhole sensor measurements. For example, method 100 may be utilized to make deep and/or ultra-deep reading resistivity measurements having a large axial spacing between the transmitter and receiver. In such embodiments, sensor subs 64 (
Deployment of transmitters and/or receivers in sensor sub 64 enables them to be axially spaced apart substantially any suitable distance (including up to several hundred feet or even a few thousand feet) to achieve a desired measurement depth. For example, electromagnetic transmitters may be deployed in LWD tool 90 (in proximity to a local power source) while the electromagnetic receivers may be deployed in sensor subs 64 at various suitable axial spacings from the transmitters. During an LWD operation, the electromagnetic measurements may be received (at 104 in
With continued reference to
With continued reference to
When making magnetic ranging measurements sensor subs 64 may employ magnetic field sensors such as a set of tri-axial magnetometers. Magnetic field measurements may be acquired while drilling (or while drilling is temporarily suspended, for example, when adding additional drill pipe to the drill string) at a number of axial locations along the BHA 50 and/or the lower portion 60 of the drill string 30. These measurements may be transmitted from the sensor subs 64 to the BHA 50 using the WDP communication link as described above. The measurements may then be processed at a processor in the BHA (e.g., in MWD tool 80 or LWD tool 90) to obtain a range and bearing (distance and direction) to the magnetic target (e.g., using triangulation techniques). Suitable processing techniques are disclosed, for example, in U.S. Pat. No. 6,985,814 which is fully incorporated herein by reference.
Method 100 may further be employed to obtain measurements of pipe stretch (which may be correlated with weight-on-bit), and/or rate of penetration of drilling. It will be understood that the term “pipe stretch” refers to a change in axial length of the drill string that may include an increase in length (pipe stretch) or a decrease in length (pipe compression). For example, measurements obtained from a number of axially spaced formation evaluation sensors (LWD sensors) may be correlated to estimate the pipe stretch and/or rate of penetration. In such embodiments, the LWD sensors are deployed in sensor subs 64 in the lower portion 60 of the drill string 30 and in the BHA 50 (e.g., in LWD tool 90). As described above with respect to
With continued reference to
The data and/or commands may be downlinked from the surface to the sensors in the lower portion of the drill string, for example, in the form of pressure pulses or drilling fluid flow rate pulse in the column of drilling fluid. These pulses may be measured using one or more pressure sensors in the sensor sub 64. The pulses may be encoded and decoded using any suitable techniques. The data and/or commands may also be downlinked, for example in the form of drill string rotation rate changes which may be measured using accelerometer and/or magnetometer sets in the sensor sub 64. These rotation rate changes may be also be encoded and decoded using any suitable techniques. Suitable techniques for transmitting data and/or commands from the surface to the sensor sub 64 are disclosed in U.S. Patent Publications 2011/0286308, 2011/0286309, 2013/0220602, and 2014/0036629, each of which is incorporated by reference in its entirety herein.
It will be understood that method 120 may advantageously improve both the speed and accuracy of the downlinking communications. In particular, moving the sensors (e.g., the drilling fluid pressure sensors) away from the drill bit and other BHA components tends to reduce noise and therefore improve the speed and accuracy of the communications in the first communication channel.
With continued reference to
It will be understood that method 140 is not limited to downlinking a command as described in the above example. Such control may also utilize a “smart” system. For example, the controller may be configured to automatically actuate the downhole tool when certain drilling conditions have been met. For example, the reamer blades may be extended when drilling a borehole having a predetermined calliper or dogleg severity. Likewise, sensors may be activated upon entering a predetermined formation (which may be established based upon real time MWD and/or LWD data). The disclosed embodiments are not limited in any of these regards.
A bottom hole assembly employing wired drill pipe and certain advantages thereof have been described in detail, it should be understood that various changes, substitutions and alternations can be made herein without departing from the spirit and scope of the disclosure as defined by the appended claims.