Patent Grant
9493985
None
This disclosure relates generally to top drive systems and methods for operating a top drive to drill a wellbore. More specifically, this disclosure relates to top drive systems that utilize hydraulic motors to provide the torque needed to rotate a drill string.
A top drive is a system that is suspended in a derrick and used to support and rotate a drill string as well as provide a conduit for the supply of pressurized drilling fluid to the drill string. A conventional top drive system includes an electric or hydraulic motor that is coupled to a drill string. In many systems, the motor is coupled to a transmission, or other gearing, and a short section of pipe, known as a quill. The quill is often coupled to the drill string by a saver sub or may be directly coupled to the upper end of the drill string.
The quill is also in fluid communication with a gooseneck, or other piping, that provides a fluid conduit for the supply of pressurized drilling fluid, or drilling mud, from the rig's mud pumps to the drill string. The drilling fluid flows through the drill pipe and into the wellbore, providing critical functions including, cooling and lubrication of the drill bit, control of wellbore pressures, and cleaning of the wellbore. Drilling fluids are often relatively high density fluids containing suspended solids and other materials designed to improve the drilling process.
Advances in drilling technology have enabled wellbores to be drilled at extreme depths and with the use of long horizontal sections. Both of these types of wellbores necessitate the use of long drill strings. As the length of the drill string increases, the power requirements of the top drive also increases. This need for increased power has been addressed by using multiple motors and/or by increasing the size of the motors being used. As the motors increase in size and/or number the size of the top drive also increases and the supply of power to the top drive motor(s) becomes increasingly challenging. The space available for a top drive is limited by the size of the derrick and high power motors often means larger sized motors.
For top drives with high-power electric motors, additional electrical generators may be needed. Additionally, the cables that supply electric power to the top drive can be prohibitively expensive and cumbersome to manage. Similarly, top drives that utilize hydraulic motors are supplied with dedicated hydraulic power units (including a fluid supply, pump, and power generator). As the power requirements of the top drive increases so do the power requirements, and likely the physical size, of the hydraulic power unit. This can also be problematic on drilling rigs where space is limited.
Thus, there is a continuing need in the art for top drive systems, and methods for operating top drive systems, that address at least some of the issues discussed above.
A top drive comprises a hydraulic motor in fluid communication with first inlet for a supply of pressurized drilling fluid. A drill string adapter is mechanically coupled to the hydraulic motor and is in fluid communication with the first inlet. In certain embodiments, the top drive includes a second inlet for the supply of pressurized drilling fluid. In certain embodiments, the hydraulic motor is in fluid communication with the first and second inlets. In certain embodiments, the top drive includes a mixing chamber in fluid communication with the second inlet and with the drill string adapter. In certain embodiments, the top drive includes a plurality of flow control devices operable to control the supply of pressurized drilling fluid from the first inlet to the hydraulic motor. In certain embodiments, the top drive includes a sensor for measuring characteristics of the pressurized drilling fluid.
In other embodiments, a drilling system includes a top drive system with a hydraulic motor that is hydraulically coupled to a mud pump. A drill string is mechanically coupled to the hydraulic motor and hydraulically coupled to the mud pump. In certain embodiments, the drilling system includes a first fluid conduit that couples the mud pump to a first inlet of the top drive system. In certain embodiments, the drilling system includes a second fluid conduit that couples the mud pump to a first inlet of the top drive system. In certain embodiments, the hydraulic motor is hydraulically coupled to the first and second inlets. In certain embodiments, the top drive system further includes a mixing chamber that is hydraulically coupled to the second inlet and to the drill string. In certain embodiments, the drilling system includes a plurality of flow control devices operable to control fluid flow from the mud pump to the hydraulic motor. In certain embodiments, the drilling system includes a control system operable to regulate the mud pump and the plurality of flow control devices.
In some embodiments, a method of operating a top drive system includes operating a mud pump to provide a pressurized drilling fluid; supplying the pressurized drilling fluid to a top drive system; passing at least a portion of the pressurized drilling fluid through a hydraulic motor that is mechanically coupled to a drill string; and passing the pressurized drilling fluid to the drill string. In certain embodiments, the method also includes measuring one or more fluid characteristics of the pressurized drilling fluid that is passed to the drill string. In certain embodiments, the method also includes regulating the mud pump or the hydraulic motor in response to the measured fluid characteristic. In certain embodiments, the method also includes regulating the mud pump or the hydraulic motor in response to a pressure input or a rotation input. In certain embodiments, all of the pressurized drilling fluid is passed through the hydraulic motor before being passed to the drill string. In certain embodiments, the pressurized drilling fluid is combined with a second supply of pressurized drilling fluid before being passed to the drill string. In certain embodiments, the pressurized drilling fluid is supplied to the top drive system through a first and second inlet, wherein the pressurized drilling fluid is supplied to first inlet at a different pressure than the pressurized drilling fluid supplied to the second inlet.
For a more detailed description of the embodiments of the present disclosure, reference will now be made to the accompanying drawings, wherein:
It is to be understood that the following disclosure describes several exemplary embodiments for implementing different features, structures, or functions of the invention. Exemplary embodiments of components, arrangements, and configurations are described below to simplify the present disclosure; however, these exemplary embodiments are provided merely as examples and are not intended to limit the scope of the invention. Additionally, the present disclosure may repeat reference numerals and/or letters in the various exemplary embodiments and across the Figures provided herein. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various exemplary embodiments and/or configurations discussed in the various figures. Moreover, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed interposing the first and second features, such that the first and second features may not be in direct contact. Finally, the exemplary embodiments presented below may be combined in any combination of ways, i.e., any element from one exemplary embodiment may be used in any other exemplary embodiment, without departing from the scope of the disclosure.
Additionally, certain terms are used throughout the following description and claims to refer to particular components. As one skilled in the art will appreciate, various entities may refer to the same component by different names, and as such, the naming convention for the elements described herein is not intended to limit the scope of the invention, unless otherwise specifically defined herein. Further, the naming convention used herein is not intended to distinguish between components that differ in name but not function. Additionally, in the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to.” All numerical values in this disclosure may be exact or approximate values unless otherwise specifically stated. Accordingly, various embodiments of the disclosure may deviate from the numbers, values, and ranges disclosed herein without departing from the intended scope. Furthermore, as it is used in the claims or specification, the term “or” is intended to encompass both exclusive and inclusive cases, i.e., “A or B” is intended to be synonymous with “at least one of A and B,” unless otherwise expressly specified herein.
Referring initially to
In operation, pressurized drilling fluid is supplied by mud pumps 112 to the top drive system 18 via the stand pipe 114 and rotary hose 116. The rotary hose 116 couples to the top drive system 118 at fluid inlet 126. Flow control devices 124A-124D are operable to divide the flow of drilling fluid between fluid conduit 128 and 130. Flow control devices 124A-124D can be adjusted to divide the drilling fluid between the fluid conduits 128, 130 so as to create a pressure differential across hydraulic motor 120. For example, maintaining a higher pressure in fluid conduit 128 than in fluid conduit 30 will result in fluid passing through the hydraulic motor 120 from fluid conduit 128 to fluid conduit 130. A plurality of flow control devices, such as valves or chokes, 124A-124D are also operable to control the pressure and flow rate of drilling fluid that is passed through fluid outlet 132 to the drill string 122.
Referring now to
The pressurized fluid supplied by the mud pumps 212 provides both the fluid energy to power the motor 220 and supply the drill string 222 with drilling fluid having the flow rate, density, and pressure necessary to perform drilling operations. In order to meet both of these needs, a control system 300 may include top drive sensors 302, downhole sensors 304, mud return sensors 306, drilling controller 308, mud pump controller 310, bottomhole pressure data input 312, and drill string rotation input 314. The controllers 308, 310 and the inputs 312, 314 may be standalone systems or may be integrated into a drilling control system such as that described in WO 2013/052165, titled Automatic Drilling System, which is incorporated by reference herein for all purposes.
Top drive sensors 302 may be integrated into the top drive system 218 and may be configured to measure characteristics of the drilling fluid at one or more locations in the top drive system 218. For example, one or more sensors 302 may measure the pressure and flow rate of fluid entering the drill string 222 as well as the differential pressure across the motor 220. Downhole sensors 304 may measure drilling fluid characteristics at or near the drill bit, or at other locations in the drill string 222. Mud return sensors 306 may be operable to measure the pressure and flow rate of drilling fluid that is returned from the wellbore.
In operation, the desired bottomhole pressure characteristics and drill string rotation characteristics are entered via inputs 312 and 314 respectively, by a system operator or other drilling control system. That data is communicated to the drilling controller 308, which analyzes the fluid characteristics measured by sensors 302, 304, and 306 in order to determine the required operating parameters of the mud pumps 212 and the motor 220. The drilling controller 308 then issues instructions to the motor control valves 224 and 226 as well as mud pump controller 310 to regulate the supply of drilling fluid to the top drive system 218. Control system 300 can operate in a continuous feedback mode where continuous adjustments are made in response to data received from the sensors.
Referring now to
Referring now to
Referring now to
While the disclosure is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and description. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the disclosure to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present disclosure.
| Number | Name | Date | Kind |
|---|---|---|---|
| 6050348 | Richarson | Apr 2000 | A |
| 20090151934 | Heidecke | Jun 2009 | A1 |
| 20110280104 | McClung, III | Nov 2011 | A1 |
| 20120024539 | Lehr | Feb 2012 | A1 |
| 20130118811 | Fagg | May 2013 | A1 |
| 20140166363 | Haci | Jun 2014 | A1 |
| Number | Date | Country |
|---|---|---|
| 2344121 | May 2000 | GB |
| 2013052165 | Apr 2013 | WO |
| Entry |
|---|
| Search Report and Written Opinion dated Dec. 12, 2014 for corresponding International Application No. PCT/US2014/046493 (77 pgs.). |
| Number | Date | Country | |
|---|---|---|---|
| 20150027782 A1 | Jan 2015 | US |
