Intelligent throttle pipe control method and system for drilling operation

Abstract

The invention relates to the technical field of throttle pipe control, and provides a throttle pipe intelligent control method and system for drilling operation, and the method comprises the steps: building a relation function of throttle pipe opening and drilling fluid flow, and building a relation function of real-time updated depth and formation pressure; after the relation fitting of the depth of the segmented change and the formation pressure is regarded as the uniform formation density in the throttle pipe opening degree control model, the flow and the hydraulic pressure corresponding to the uniform formation density are correlated through the Bernoulli equation, the flow needing to be adjusted is obtained through calculation, and the corresponding throttle pipe opening degree is obtained according to the flow needing to be adjusted through the relation function. The drilling fluid pressure is sent to the throttle manifold control module to adjust a throttle pipe, and the hydraulic pressure of the drilling fluid is quickly adjusted, so that the hydraulic pressure can more effectively balance the overall well wall formation pressure, and the hidden danger of the formation pressure to drilling under the change of the drilling depth is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of throttle tube control, and in particular to a throttle tube intelligent control method and system for drilling operations. Background Art

[0002] During the drilling operation, the well wall will be subjected to formation pressure. Drilling fluid is used as the medium for circulating flushing in the well, and the density of the drilling fluid is set to a certain extent so that the liquid pressure balances the formation pressure and protects the well wall.

[0003] As the drilling depth increases, the formation pressure will also increase, but the rock density in different rock layers will change, and the pressure of the rock pore fluid will change, so the change in formation pressure will also be non-uniform. At this time, the density of the drilling fluid needs to be adjusted to match the formation pressure, but the change in the density of the drilling fluid requires readjustment and the use of weighting agents or dilution. If the density control is not timely, the pressure difference on the well wall will bring hidden dangers to the drilling operation. Summary of the invention

[0004] The present invention provides a throttle tube intelligent control method for drilling operations, which is used to solve the problems in the prior art that when the formation pressure changes with depth during drilling operations, the density of the drilling fluid does not change in time, and the drilling fluid hydraulic pressure has a poor balancing effect on the formation pressure.

[0005] A first aspect of the present invention provides a choke tube intelligent control method for drilling operations, comprising:

[0006] Obtain the historical records of the choke opening adjustment and the drilling fluid flow rate, and establish a relationship function between the choke opening and the drilling fluid flow rate;

[0007] The formation pressure record of the logging while drilling is obtained, and a function of the relationship between depth and formation pressure is established. The function of the relationship between depth and formation pressure is updated with real-time data, and the current drilling fluid density is obtained, and a choke opening control model is established to obtain a choke opening adjustment value. The choke opening control model is specifically as follows:

[0008]

[0009] Among them, h1 is the depth of the wellhead, h2 is the depth of the bottom of the well, and f(h) is the relationship function between formation pressure and depth. is the average formation density, g is the gravitational acceleration, ρ 液 is the drilling fluid density, f(k) is the relationship function between the choke opening and the drilling fluid flow rate, A is the wellbore cross-sectional area at depth H, H is the depth of the sampling point in the drilling wellbore, C is the Bernoulli equation constant, and k is the choke opening adjustment value;

[0010] The throttle pipe opening adjustment value is sent to the throttle manifold control module.

[0011] Optionally, the step of sending the throttle tube opening adjustment value to the throttle manifold control module is as follows:

[0012] The average formation density is substituted into the pressure difference judgment model. When the average formation density satisfies the pressure difference judgment model, the throttle tube opening adjustment value is sent to the throttle manifold control module. The pressure difference judgment model is specifically:

[0013]

[0014] Wherein, Q is the preset safety pressure difference value, and h is any depth value in the interval (h1, h2).

[0015] Optionally, after obtaining the throttle tube opening adjustment value, the method further includes:

[0016] If the throttle tube opening adjustment value exceeds the throttle tube opening adjustment range, the difference between the throttle tube opening adjustment value and the throttle tube opening extreme value is calculated, and the boost valve is adjusted based on the difference.

[0017] The second aspect of the present application provides a choke tube intelligent control system for drilling operations, comprising:

[0018] A choke tube opening data acquisition module is used to acquire the choke tube opening adjustment history records and the drilling fluid flow history records, and establish a relationship function between the choke tube opening and the drilling fluid flow;

[0019] The opening adjustment value calculation module is used to obtain the formation pressure record of the logging while drilling, establish the relationship function between depth and formation pressure, update the relationship function between depth and formation pressure with real-time data, obtain the current drilling fluid density, establish the choke opening control model, and obtain the choke opening adjustment value. The choke opening control model is specifically as follows:

[0020]

[0021] Among them, h1 is the depth of the wellhead, h2 is the depth of the bottom of the well, and f(h) is the relationship function between formation pressure and depth. is the average formation density, g is the gravitational acceleration, ρ 液 is the drilling fluid density, f(k) is the relationship function between the choke opening and the drilling fluid flow rate, A is the wellbore cross-sectional area at depth H, H is the depth of the sampling point in the drilling wellbore, C is the Bernoulli equation constant, and k is the choke opening adjustment value;

[0022] The throttle tube control module is used to send the throttle tube opening adjustment value to the throttle manifold control module.

[0023] Optionally, in the throttle tube control module, sending the throttle tube opening adjustment value to the throttle manifold control module is specifically:

[0024] The average formation density is substituted into the pressure difference judgment model. When the average formation density satisfies the pressure difference judgment model, the throttle tube opening adjustment value is sent to the throttle manifold control module. The pressure difference judgment model is specifically:

[0025]

[0026] Wherein, Q is the preset safety pressure difference value, and h is any depth value in the interval (h1, h2).

[0027] Optionally, after obtaining the throttle tube opening adjustment value, the opening adjustment value calculation module further includes:

[0028] If the throttle tube opening adjustment value exceeds the throttle tube opening adjustment range, the difference between the throttle tube opening adjustment value and the throttle tube opening extreme value is calculated, and the boost valve is adjusted based on the difference.

[0029] The third aspect of the present application provides a choke tube intelligent control method device for drilling operations, the device comprising a processor and a memory:

[0030] The memory is used to store program code and transmit the program code to the processor;

[0031] The processor is used to execute the intelligent control method of a throttle tube for drilling operations as described in any one of the first aspects of the present invention according to the instructions in the program code.

[0032] A fourth aspect of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium is used to store program code, and the program code is used to execute a throttle tube intelligent control method for drilling operations as described in any one of the first aspects of the present invention.

[0033] It can be seen from the above technical scheme that the present invention has the following advantages: by establishing a relationship function between the throttle tube opening and the drilling fluid flow rate, and establishing a real-time updated relationship function between the depth and the formation pressure, in the throttle tube opening control model, the segmented depth and formation pressure relationship is fitted as a uniform formation density, and the flow rate is associated with the hydraulic pressure corresponding to the uniform formation density using the Bernoulli equation, the flow rate that needs to be adjusted is calculated, and the corresponding throttle tube opening is obtained according to the relationship function according to the flow rate to be adjusted, and sent to the throttle manifold control module to adjust the throttle tube, and the drilling fluid hydraulic pressure is quickly adjusted, so that the hydraulic pressure can more effectively balance the overall wellbore formation pressure, and reduce the hidden dangers of the formation pressure to drilling under the change of drilling depth. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0035] Figure 1 A flowchart of a choke tube intelligent control method for drilling operations;

[0036] Figure 2 The figure is a structural diagram of a choke tube intelligent control system used in drilling operations. DETAILED DESCRIPTION

[0037] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] The present invention provides a throttle tube intelligent control method for drilling operations, which is used to solve the problems in the prior art that when the formation pressure changes with depth during drilling operations, the density of the drilling fluid does not change in time, and the drilling fluid hydraulic pressure has a poor balancing effect on the formation pressure.

[0039] See also Figure 1 , Figure 1 The present invention provides a first flow chart of a throttle tube intelligent control method for drilling operations.

[0040] S100, obtaining the historical records of the choke opening adjustment and the drilling fluid flow rate, and establishing a relationship function between the choke opening and the drilling fluid flow rate;

[0041] It should be noted that the throttle tube, as part of the drilling throttle manifold system, can be used to adjust the drilling fluid pressure and control the flow rate. While the drilling fluid enters the bottom of the well through the drill bit of the drill tool, it will also pass through the throttle valve and the overflow valve into the tube of the drilling throttle manifold for collection and processing. The throttle tube adjusts the flow rate of the drilling fluid to better ensure the effect of the drilling fluid. In the process of the throttle manifold system adjusting the drilling fluid with the opening degree of the throttle tube, the record is kept. The larger the throttle tube opening, the greater the flow rate of the drilling fluid, and the greater the flow rate of the drilling fluid, and a relationship function between the throttle tube opening and the drilling fluid flow rate is established.

[0042] S200, obtaining the formation pressure record of the logging while drilling, establishing a depth-formation pressure relationship function, updating the depth-formation pressure relationship function with real-time data, and obtaining the current drilling fluid density, establishing a choke opening control model, and obtaining a choke opening adjustment value, wherein the choke opening control model is specifically:

[0043]

[0044] Among them, h1 is the depth of the wellhead, h2 is the depth of the bottom of the well, and f(h) is the relationship function between formation pressure and depth. is the average formation density, g is the gravitational acceleration, ρ 液 is the drilling fluid density, f(k) is the relationship function between the choke opening and the drilling fluid flow rate, A is the wellbore cross-sectional area at depth H, H is the depth of the sampling point in the drilling wellbore, C is the Bernoulli equation constant, and k is the choke opening adjustment value;

[0045] It should be noted that the formation rock structure at the location of the drilling operation can be measured by logging while drilling. The formation rock physical parameters can be measured during the drilling process, and the measurement results can be sent to the ground for processing in real time using a data telemetry system. During the drilling operation, a depth meter can be configured at the drill bit to obtain the real-time depth of the drill bit. In this embodiment, the depth refers to the horizontal distance between the wellhead and the drill bit. By recording the correlation data of the drill bit depth and time during the drilling operation, the relationship between the depth and time in the current drilling operation is obtained. Then, through the correlation data of the formation pressure and time recorded by the logging while drilling, the relationship between the formation pressure and time under the formation condition of the current drilling operation is obtained. With time as the correlation, a depth and formation pressure relationship function is established. As the drill bit depth of the drilling operation changes, the formation pressure data received in real time updates the depth and formation pressure relationship function.

[0046] The density of the drilling fluid has been adjusted before being injected into the well. However, with the subsequent drilling operation, the density of the drilling fluid can be adjusted by increasing the weight or diluting it with clean water to make the density of the drilling fluid match the formation pressure. The density adjustment of the drilling fluid will be recorded, and the real-time drilling fluid density will be substituted into the model when establishing the choke opening control model. In the process from the wellhead depth h1 to the well bottom depth h2, multiple formations will be passed through. The formation pressure and depth relationship function f(h) reflects the formation pressure characteristics of multiple formations. f(h) is actually a piecewise function combining multiple segment functions. In the choke opening control model, the first formula regards the wellhead to the well bottom as a uniform formation, and the formation pressure under uniform formation density is only related to the depth. The average formation density under the uniform formation is calculated. According to the Bernoulli equation, the kinetic energy and potential of the drilling fluid can be obtained. The relationship between energy and pressure potential energy at a certain depth. When it is necessary to change the drilling fluid pressure by adjusting the throttle opening to offset the formation pressure, the pressure can be replaced by the corresponding formation pressure, and the flow rate parameter is replaced by the relationship function between the opening and the flow rate divided by the cross-sectional area. The throttle opening control model reflects that the throttle opening can be changed to change the flow rate of the drilling fluid in the wellbore to adjust the flow rate, and finally the liquid pressure on the wellbore wall can be adjusted. Any depth H in the wellbore without a throttle manifold can be used as a sampling point to be substituted into the second formula of the throttle opening control model, and the cross-sectional area is the cross-sectional area of ​​the wellbore at the depth corresponding to H. In the vertical well drilling, the wellbore diameter remains unchanged, while the cross-sectional area of ​​the trapezoidal well or throat well will gradually become thinner. The corresponding cross-sectional area needs to be obtained according to the depth H. The cross-sectional area corresponding to the wellbore depth will be recorded during the drilling process.

[0047] The density of the drilling fluid in the wellbore is consistent. Although the drilling fluid pressure adjusted under the throttle opening cannot achieve the best balancing effect on the formation pressure at all locations in the wellbore, it is optimal overall.

[0048] S300, sending the throttle pipe opening adjustment value to the throttle manifold control module.

[0049] It should be noted that the control module in the throttle manifold control box can realize corresponding actions, data collection, related control logic judgment and execution, and complete the configuration of related interfaces and automatic data control with the terminal equipment through the Internet to realize remote control of the throttle switch; after the throttle tube opening adjustment value is sent to the throttle manifold, the drilling fluid hydraulic pressure can be quickly adjusted, so that the hydraulic pressure can more effectively balance the overall wellbore formation pressure, but it is only a temporary balance for the real-time changing formation pressure and rock gap density, and the density of the drilling fluid still needs to be adjusted later; in addition to being suitable for pressure control during drilling, this embodiment can also be used to kill the well when overflow occurs in an empty well. When the accumulated throttle tube opening adjustment value reaches a preset threshold after a period of operation, the throttle manifold control module can communicate online to send an alarm to the operation and maintenance personnel of the drilling operation and maintenance control center, indicating that there is an abnormal pressure change, and indicating the drilling fluid density that needs to be adjusted according to the accumulated throttle tube opening adjustment value, so that the operation and maintenance personnel can quickly respond to drilling safety and maintain drilling safety in time.

[0050] In this embodiment, by establishing a relationship function between the throttle tube opening and the drilling fluid flow rate, and establishing a real-time updated relationship function between the depth and the formation pressure, in the throttle tube opening control model, the segmented variation in the depth and the formation pressure relationship is fitted as a uniform formation density, and the flow rate is associated with the hydraulic pressure corresponding to the uniform formation density using the Bernoulli equation, the flow rate that needs to be adjusted is calculated, and the corresponding throttle tube opening is obtained according to the relationship function based on the flow rate to be adjusted, and sent to the throttle manifold control module to adjust the throttle tube, and the drilling fluid hydraulic pressure is quickly adjusted so that the hydraulic pressure can more effectively balance the overall wellbore formation pressure and reduce the hidden dangers of formation pressure to drilling under changes in drilling depth.

[0051] The above is a detailed description of the first embodiment of a throttle tube intelligent control method for drilling operations provided by the present application. The following is a detailed description of the second embodiment of a throttle tube intelligent control method for drilling operations provided by the present application.

[0052] In this embodiment, a choke tube intelligent control method for drilling operations is further provided. In the aforementioned step S300, the choke tube opening adjustment value is sent to the choke manifold control module specifically as follows:

[0053] The average formation density is substituted into the pressure difference judgment model. When the average formation density satisfies the pressure difference judgment model, the throttle tube opening adjustment value is sent to the throttle manifold control module. The pressure difference judgment model is specifically:

[0054]

[0055] Wherein, Q is the preset safety pressure difference value, and h is any depth value in the interval (h1, h2);

[0056] It should be noted that the density of the drilling fluid needs to be reasonably set during the drilling operation. When the density of the drilling fluid is too high, the formation will be leaked and the wellbore wall will be crushed. Therefore, in this embodiment, when adjusting the throttle opening, the formation with low rock gap density needs to be considered to prevent the pressure difference between the drilling fluid hydraulic pressure and the formation after adjusting the throttle opening from being too large. In the established pressure difference judgment model, the pressure difference between the drilling wellbore depth h1 to the drilling bottom depth h2 and the fitted equivalent average formation density will be traversed. When the fitted equivalent pressure difference can all meet the requirement of being less than the preset safety pressure difference value, it can be ensured that the drilling fluid pressure increased by the throttle opening will not crush the wellbore wall at the place where the formation rock gap density is the smallest. The preset safety pressure difference value is set according to the structure, material and parameters of the wellbore wall.

[0057] Further, in the aforementioned step S200, after obtaining the throttle tube opening adjustment value, it also includes: if the throttle tube opening adjustment value exceeds the throttle tube opening adjustment range, then calculating the difference between the throttle tube opening adjustment value and the throttle tube opening extreme value, and adjusting the boost valve with the difference; it should be noted that the throttle valve opening has adjustment restrictions, and the aforementioned relationship function f(k) between the throttle tube opening and the drilling fluid flow rate is only valid within a certain opening range, but in the calculation of the throttle tube opening control model, the opening adjustment value calculated to meet the formation pressure may exceed the adjustment range of the throttle tube. At this time, the boost valve in the throttle manifold can be adjusted according to the opening value of the excess part, and combined with the control, the boost valve adjustment value calculation can refer to the model:

[0058]

[0059] Among them, P 增 k is the boost value that the boost valve needs to adjust, 调 is the throttle tube opening adjustment value, k max is the extreme value of the throttle opening; according to the pressure regulation of the booster valve, the boost value P that the booster valve needs to adjust 增 The boost valve is controlled in conjunction with the throttle tube to control the hydraulic pressure of the drilling fluid.

[0060] The above is a detailed description of an intelligent control method for a throttle tube for drilling operations provided in the first aspect of the present application. The following is a detailed description of an embodiment of an intelligent control system for a throttle tube for drilling operations provided in the second aspect of the present application.

[0061] See also Figure 2 , Figure 2 This embodiment provides a choke tube intelligent control system for drilling operations, including:

[0062] A choke opening data acquisition module 10 is used to acquire the choke opening adjustment history records and the drilling fluid flow history records, and establish a relationship function between the choke opening and the drilling fluid flow;

[0063] The opening adjustment value calculation module 20 is used to obtain the formation pressure record of the logging while drilling, establish the relationship function between the depth and the formation pressure, update the relationship function between the depth and the formation pressure with real-time data, and obtain the current drilling fluid density, establish the choke opening control model, and obtain the choke opening adjustment value. The choke opening control model is specifically:

[0064]

[0065] Among them, h1 is the depth of the wellhead, h2 is the depth of the bottom of the well, and f(h) is the relationship function between formation pressure and depth. is the average formation density, g is the gravitational acceleration, ρ 液 is the drilling fluid density, f(k) is the relationship function between the choke opening and the drilling fluid flow rate, A is the wellbore cross-sectional area at depth H, H is the depth of the sampling point in the drilling wellbore, C is the Bernoulli equation constant, and k is the choke opening adjustment value;

[0066] The throttle tube control module 30 is used to send the throttle tube opening adjustment value to the throttle manifold control module.

[0067] Furthermore, in the throttle tube control module 30, the throttle tube opening adjustment value is sent to the throttle manifold control module specifically as follows:

[0068] The average formation density is substituted into the pressure difference judgment model. When the average formation density satisfies the pressure difference judgment model, the throttle tube opening adjustment value is sent to the throttle manifold control module. The pressure difference judgment model is specifically:

[0069]

[0070] Wherein, Q is the preset safety pressure difference value, and h is any depth value in the interval (h1, h2).

[0071] Furthermore, after obtaining the throttle tube opening adjustment value, the opening adjustment value calculation module 20 further includes:

[0072] If the throttle tube opening adjustment value exceeds the throttle tube opening adjustment range, the difference between the throttle tube opening adjustment value and the throttle tube opening extreme value is calculated, and the boost valve is adjusted according to the difference; the throttle manifold system includes an explosion-proof solenoid valve group, an explosion-proof PLC electronic control system, terminal equipment, and a hydraulic throttle manifold control box. The corresponding action of the explosion-proof solenoid valve group is judged and executed through the data acquisition-related control logic of the explosion-proof PLC electronic control system to achieve remote control of the throttle switch.

[0073] The third aspect of the present application also provides a throttle tube intelligent control method device for drilling operations, including a processor and a memory: the memory is used to store program code and transmit the program code to the processor; the processor is used to execute the above-mentioned throttle tube intelligent control method for drilling operations according to the instructions in the program code.

[0074] A fourth aspect of the present application provides a computer-readable storage medium, characterized in that the computer-readable storage medium is used to store program codes, and the program codes are used to execute the above-mentioned throttle tube intelligent control method for drilling operations.

[0075] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and equipment can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0076] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0077] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0078] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0079] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0080] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A choke tube intelligent control method for drilling operations, characterized in that include: Obtain the historical records of the choke opening adjustment and the drilling fluid flow rate, and establish a relationship function between the choke opening and the drilling fluid flow rate; The formation pressure record of the logging while drilling is obtained, and a function of the relationship between depth and formation pressure is established. The function of the relationship between depth and formation pressure is updated with real-time data, and the current drilling fluid density is obtained, and a choke opening control model is established to obtain a choke opening adjustment value. The choke opening control model is specifically as follows: Among them, h1 is the depth of the wellhead, h2 is the depth of the bottom of the well, and f(h) is the relationship function between formation pressure and depth. is the average formation density, g is the gravitational acceleration, ρ 液 is the drilling fluid density, f(k) is the relationship function between the choke opening and the drilling fluid flow rate, A is the wellbore cross-sectional area at depth H, H is the depth of the sampling point in the drilling wellbore, C is the Bernoulli equation constant, and k is the choke opening adjustment value; The throttle pipe opening adjustment value is sent to the throttle manifold control module.

2. The intelligent control method for a choke tube used in drilling operations according to claim 1, characterized in that: The method of sending the throttle tube opening adjustment value to the throttle manifold control module is as follows: The average formation density is substituted into the pressure difference judgment model. When the average formation density satisfies the pressure difference judgment model, the throttle tube opening adjustment value is sent to the throttle manifold control module. The pressure difference judgment model is specifically: Wherein, Q is the preset safety pressure difference value, and h is any depth value in the interval (h1, h2).

3. The intelligent control method for a choke tube used in drilling operations according to claim 1, characterized in that: After obtaining the throttle tube opening adjustment value, the method further includes: If the throttle tube opening adjustment value exceeds the throttle tube opening adjustment range, the difference between the throttle tube opening adjustment value and the throttle tube opening extreme value is calculated, and the boost valve is adjusted based on the difference.

4. A choke tube intelligent control system for drilling operations, characterized in that: include: A choke tube opening data acquisition module is used to acquire the choke tube opening adjustment history records and the drilling fluid flow history records, and establish a relationship function between the choke tube opening and the drilling fluid flow; The opening adjustment value calculation module is used to obtain the formation pressure record of the logging while drilling, establish the relationship function between depth and formation pressure, update the relationship function between depth and formation pressure with real-time data, obtain the current drilling fluid density, establish the choke opening control model, and obtain the choke opening adjustment value. The choke opening control model is specifically as follows: Among them, h1 is the depth of the wellhead, h2 is the depth of the bottom of the well, and f(h) is the relationship function between formation pressure and depth. is the average formation density, g is the gravitational acceleration, ρ 液 is the drilling fluid density, f(k) is the relationship function between the choke opening and the drilling fluid flow rate, A is the wellbore cross-sectional area at depth H, H is the depth of the sampling point in the drilling wellbore, C is the Bernoulli equation constant, and k is the choke opening adjustment value; The throttle tube control module is used to send the throttle tube opening adjustment value to the throttle manifold control module.

5. The intelligent control system for choke tube used in drilling operation according to claim 4, characterized in that: In the throttle tube control module, the throttle tube opening adjustment value is sent to the throttle manifold control module specifically as follows: The average formation density is substituted into the pressure difference judgment model. When the average formation density satisfies the pressure difference judgment model, the throttle tube opening adjustment value is sent to the throttle manifold control module. The pressure difference judgment model is specifically: Wherein, Q is the preset safety pressure difference value, and h is any depth value in the interval (h1, h2).

6. The intelligent control system for choke tube used in drilling operation according to claim 4, characterized in that: In the opening adjustment value calculation module, after obtaining the throttle tube opening adjustment value, the following further comprises: If the throttle tube opening adjustment value exceeds the throttle tube opening adjustment range, the difference between the throttle tube opening adjustment value and the throttle tube opening extreme value is calculated, and the boost valve is adjusted based on the difference.

7. A choke tube intelligent control device for drilling operations, characterized in that: The device comprises a processor and a memory: The memory is used to store program code and transmit the program code to the processor; The processor is used to execute the intelligent control method of a choke tube for drilling operations as described in any one of claims 1 to 3 according to the instructions in the program code.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store program codes, and the program codes are used to execute the choke tube intelligent control method for drilling operations as described in any one of claims 1-3.

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