Method, system and device for designing pressure-control drilling well-killing heavy slurry cap for leakage formation

Abstract

The invention belongs to the technical field of petroleum drilling engineering, particularly relates to a method, a system and a device for designing a pressure-controlled drilling, pulling-out and well killing heavy slurry cap for a leakage formation, and aims to solve the problem that a method for designing a pressure-controlled drilling, pulling-out and well killing heavy slurry cap which comprehensively considers bottom hole pressure balance, material balance and drilling crew operation time does not exist in the prior art. The method comprises the steps that a pressure-controlled dynamic formation leakage test is carried out, and the actual relation among wellhead back pressure, bottom hole pressure and formation leakage is determined; setting the drilling fluid leakage rate and the drilling crew operation time according to the allowable original density; stratum pollution factors are considered at the heavy slurry position of the shaft; and establishing a design method flow by adopting target orientation. The method is clear in thought and clear in principle, the single well difference is fully considered, verification data is adopted as a design basis, and higher applicability is achieved.

Description

Background Art

[0002] As oil and gas exploration and development move deeper into unconventional and difficult-to-use reservoirs, the formations being drilled are becoming more and more complex, with the formation pressure system becoming more complex and the formation narrow safety density window becoming more and more prominent. Managed pressure drilling technology can achieve closed wellbore circulation, early leakage monitoring, and flexible and rapid wellhead back pressure control. Combined with existing drilling technology, it can effectively solve the above-mentioned drilling problems with complex formation pressure systems and narrow safety density windows.

[0003] Controlled pressure drilling is an important process of controlled pressure drilling technology. The general process is to pressurize the water hole, control the pressure to drill to the designed well section, inject the heavy slurry cap, make the bottom hole pressure greater than the formation pressure, reduce the wellhead back pressure to zero, pull out the wellhead rotation control device sealed bearing assembly, and continue to inject the original density drilling fluid in subsequent drilling until the drill bit is pulled out of the wellhead. Among them, the design of the heavy slurry cap for well pressure control is of great significance to the safety of the drilling process. The existing design of the heavy slurry cap for controlled pressure drilling mainly considers the designed heavy slurry drilling fluid density, the injection volume of the heavy slurry drilling fluid, and the injection position of the heavy slurry drilling fluid. It solves the problem of general controlled pressure drilling in field applications, but the design method considers factors that are too ideal and is not suitable for complex substrates.

[0004] Therefore, it is very necessary to study a design method for a controlled pressure drilling and well-killing heavy grouting cap that comprehensively considers the bottom hole pressure balance, material balance, and well crew operation time, has a scientific principle, a simple process, and is highly adaptable. Based on this, the present invention provides a design method, system, and device for a controlled pressure drilling and well-killing heavy grouting cap for a lost formation. Summary of the invention

[0005] In order to solve the above-mentioned problems in the prior art, namely, the problem that the prior art does not have a method for designing a heavy grouting cap for pressure-controlled drilling that comprehensively considers the bottom hole pressure balance, material balance, and well crew operation time, the present invention provides a method, system, and device for designing a heavy grouting cap for pressure-controlled drilling that is used in lost formations.

[0006] In one aspect of the present invention, a method for designing a heavy grouting cap for controlling drilling and well killing in a lost formation is provided, which is used to calculate the injection volume of the heavy grouting cap for drilling and well killing and the maximum hydrostatic column pressure when the heavy grouting cap is injected. The method comprises:

[0007] Performing a pressure-controlled formation leakage dynamic test on the wellbore to obtain dynamic test data, obtaining bottom hole pressure based on the dynamic test data, and then obtaining a bottom hole pressure-leakage rate relationship in combination with the dynamic data;

[0008] Get the set allowable original density drilling fluid loss rate Q p , and based on the Q p and the drilling operation time to calculate the total leakage; combined with the Q pand the bottom hole pressure-leakage rate relationship, calculate the maximum hydrostatic column pressure when injecting the heavy slurry cap;

[0009] The height of the liquid column of the heavy slurry cap is calculated based on the wellhead back pressure measured by the dynamic test data; and the volume of the heavy slurry cap injected into the wellbore is calculated based on the height of the liquid column of the heavy slurry cap.

[0010] In some preferred embodiments, the dynamic test data is obtained by:

[0011] Obtain the minimum wellhead back pressure P that can balance the invasion of formation fluid into the wellbore during drilling b , will be with the P b The corresponding leakage rate is recorded as Q loss ;

[0012] Continuously reduce the mud pump drilling fluid flow rate into the well and increase the wellhead back pressure until the mud pump flow rate into the well is zero, and adjust the wellhead back pressure at this time to the leakage rate equal to the minimum wellhead back pressure P b Corresponding leakage rate Q loss , record the wellhead back pressure P at this time bq , the P bq As dynamic test data.

[0013] In some preferred embodiments, the bottom hole pressure P wb , and the method to obtain it is:

[0014] P wb =P h +P bq ;

[0015] Among them, the P h is the static column pressure of the original density drilling fluid, that is, the dynamic test data P bq The corresponding hydrostatic column pressure.

[0016] In some preferred embodiments, the bottom hole pressure-leakage rate relationship is obtained by:

[0017] According to the P wb and the Q loss P is obtained by interpolation or fitting. wb =g(Q loss ) calculation model, wherein the calculation model is the bottom hole pressure-leakage rate relationship.

[0018] In some preferred embodiments, the total leakage amount is calculated as follows:

[0019] V loss =Topt×Q p ;

[0020] Among them, the V loss is the total leakage volume, and Topt is the tripping time;

[0021] The maximum hydrostatic column pressure when the heavy slurry cap is injected is calculated as follows:

[0022] The Q p As Q loss , is brought into the calculation model of the bottom hole pressure-loss rate relationship, and the Q p The corresponding bottom hole pressure P wb ;

[0023] According to the bottom hole pressure P wb and the hydrostatic column pressure P of the remaining slurry ho , calculate the maximum hydrostatic column pressure P when injecting heavy slurry cap hh :

[0024] P wb =P hh +P ho .

[0025] In some preferred embodiments, the liquid column height ΔH of the heavy slurry cap is h , which is calculated as:

[0026] P bq =ΔρgΔH h ;

[0027] Wherein, the Δρ is the increase in the density of the heavy slurry cap compared to the original drilling fluid density.

[0028] In some preferred embodiments, the volume of the heavy slurry cap injected into the wellbore is calculated as follows:

[0029]

[0001] Among them, i is the corresponding number of the discrete unit in the wellbore space, ΔH is the discrete unit height of the heavy slurry cap in the wellbore, θ is the well inclination angle of the discrete unit, and A is the cross-sectional area of ​​the discrete unit.

[0002] Another aspect of the present invention provides a system for designing a pressure-controlled drilling and well-killing heavy grouting cap for a lost formation. Based on a method for designing a pressure-controlled drilling and well-killing heavy grouting cap for a lost formation, the system comprises:

[0003] A dynamic test module, configured to perform a pressure-controlled formation leakage dynamic test on the pull-out well, obtain dynamic test data, obtain bottom hole pressure based on the dynamic test data, and then obtain a bottom hole pressure-leakage rate relationship in combination with the dynamic data;

[0004] The first parameter calculation module obtains the set allowable original density drilling fluid loss rate Q p , and based on the Q p and the drilling operation time to calculate the total leakage; combined with the Q p and the bottom hole pressure-leakage rate relationship, calculate the maximum hydrostatic column pressure when injecting the heavy slurry cap;

[0005] The second parameter calculation module calculates the height of the liquid column of the heavy slurry cap according to the wellhead back pressure measured by the dynamic test data; and calculates the volume of the heavy slurry cap injected into the wellbore based on the height of the liquid column of the heavy slurry cap.

[0006] A third aspect of the present invention provides a storage device storing a plurality of programs, wherein the programs are suitable for being loaded and executed by a processor to implement a method for designing a heavy grouting cap for pressure-controlled drilling and well-killing in a lost formation.

[0007] In a fourth aspect of the present invention, a processing device is provided, comprising a processor and a storage device; the processor is adapted to execute various programs; the storage device is adapted to store a plurality of programs; the programs are adapted to be loaded and executed by the processor to implement a method for designing a heavy grouting cap for controlling pressure in drilling and well killing in a lost formation

[0008] Beneficial effects of the present invention:

[0009] The present invention is based on the leakage target and determines the specific relationship between the leakage amount and the wellhead back pressure and the bottom hole pressure through field testing, so the design basis is sufficient; the well killing heavy slurry cap is designed through a precise target-oriented process, and the determination target is clear; the process is simple and the operation is easy. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0011] Figure 1 It is a schematic diagram of the managed pressure drilling equipment system and dynamic formation leakage test in the present invention;

[0012] Figure 2 This is the design process of the managed pressure drilling heavy slurry cap in the present invention;

[0013] Figure 3 It is a schematic diagram of the relationship curve between the measured bottom hole pressure and the leakage rate in the present invention;

[0014] Figure 4 It is a schematic diagram of heavy slurry injection in the present invention;

[0015] Figure 5 Schematic diagram of drilling fluid loss during the drilling process in the present invention;

[0016] Figure 6 It is a structural diagram of a computer system of a server for implementing the method, system, and device embodiments of the present application. DETAILED DESCRIPTION

[0017] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It is also necessary to explain that, for ease of description, only the parts related to the relevant invention are shown in the accompanying drawings.

[0018] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0019] The first embodiment of the present invention, see Figure 1 -5, provides a method for designing a heavy grouting cap for pressure-controlled drilling and wellbore in a lost formation, which is used to calculate the injection volume of the heavy grouting cap for drilling and wellbore and the maximum hydrostatic column pressure when the heavy grouting cap is injected. The method includes:

[0020] Performing a pressure-controlled formation leakage dynamic test on the wellbore to obtain dynamic test data, obtaining bottom hole pressure based on the dynamic test data, and then obtaining a bottom hole pressure-leakage rate relationship in combination with the dynamic data;

[0021] Get the set allowable original density drilling fluid loss rate Q p , and based on the Q p and the drilling operation time to calculate the total leakage; combined with the Q p and the bottom hole pressure-leakage rate relationship, calculate the maximum hydrostatic column pressure when injecting the heavy slurry cap;

[0022] The height of the liquid column of the heavy slurry cap is calculated based on the wellhead back pressure measured by the dynamic test data; and the volume of the heavy slurry cap injected into the wellbore is calculated based on the height of the liquid column of the heavy slurry cap.

[0023] Among them, after completing the above design, the drilling operation is completed according to the pressure-controlled drilling process.

[0024] Preferably, see Figure 1 , the dynamic test data is obtained by:

[0025] Obtain the minimum wellhead back pressure P that can balance the invasion of formation fluid into the wellbore during drilling b , will be with the P b The corresponding leakage rate is recorded as Q loss ;

[0026] Continuously reduce the mud pump drilling fluid flow rate into the well and increase the wellhead back pressure until the mud pump flow rate into the well is zero, and adjust the wellhead back pressure at this time to the leakage rate equal to the minimum wellhead back pressure P b Corresponding leakage rate Q loss , record the wellhead back pressure P at this time bq , the P bq As dynamic test data.

[0027] Preferably, the bottom hole pressure P wb , and the method to obtain it is:

[0028] P wb =P h +P bq ;

[0029] Among them, the P h is the static column pressure of the original density drilling fluid, that is, the dynamic test data P bq The corresponding hydrostatic column pressure.

[0030] Among them, the leakage rate when the wellbore is circulated and the wellbore is stopped is the same, so it can be considered that the bottom hole pressure of the two is the same, both P wb In the prior art, the bottom hole pressure P wb is the hydrostatic column pressure P h With wellhead return P b , annular flow friction P f The calculation of the annular flow friction is based on a semi-empirical theoretical formula, which requires multiple empirical parameters and is difficult to calculate accurately.

[0031] Bottom hole pressure P when wellbore circulation stops wb is the hydrostatic column pressure P h The wellhead back pressure F recorded by the pressure-controlled formation leakage test bq The above content can be used to calculate the bottom hole pressure P without calculating the annular flow friction. wb Since there is no need to calculate the annular flow friction, the calculated bottom hole pressure is more accurate.

[0032] Preferably, the bottom hole pressure-leakage rate relationship is obtained by:

[0033] According to the P wb and the Q loss P is obtained by interpolation or fitting. wb =g(Q loss ) calculation model, wherein the calculation model is the bottom hole pressure-leakage rate relationship.

[0034] Among them, Figure 3As shown, this is a curve of bottom hole pressure and leakage rate recorded in a certain well; the yx equation is obtained by polynomial fitting, and the dotted line is the yx equation curve.

[0035] Preferably, the total leakage amount is calculated as follows:

[0036] V loss =Topt×Q p ;

[0037] Among them, the V loss is the total leakage volume, and Topt is the tripping time;

[0038] The drilling operation time Topt is generally determined by the performance of the on-site equipment and the work efficiency of the operators, and varies from construction unit to construction unit. The Topt is used to determine the allowable original density drilling fluid loss rate Q according to the empirical value. p , should satisfy V loss <V org , V org Reserve mud volume for the site.

[0039] The maximum hydrostatic column pressure when the heavy slurry cap is injected is calculated as follows:

[0040] The Q p As Q loss , is brought into the calculation model of the bottom hole pressure-loss rate relationship, and the Q p The corresponding bottom hole pressure P wb ;

[0041] According to the bottom hole pressure P wb and the hydrostatic column pressure P of the remaining slurry ho , calculate the maximum hydrostatic column pressure P when injecting heavy slurry cap hh :

[0042] P wb =P hh +P ho .

[0043] Preferably, see Figure 4 , Figure 5 , the liquid column height ΔH of the heavy slurry cap h , which is calculated as:

[0044] P bq =ΔρgΔH h ;

[0045] Wherein, the Δρ is the increase in the density of the heavy slurry cap compared to the original drilling fluid density.

[0046] Preferably, the volume of the heavy slurry cap injected into the wellbore is calculated as follows:

[0047]

[0048] Among them, i is the corresponding number of the discrete unit in the wellbore space, ΔH is the discrete unit height of the heavy slurry cap in the wellbore, θ is the well inclination angle of the discrete unit, and A is the cross-sectional area of ​​the discrete unit.

[0049] Preferably, see Figure 4 , Figure 5 , determine whether the casing shoe is located in the vertical well section; if so, calculate the bottom well depth H of the heavy slurry cap column based on the total leakage, the well depth at the casing shoe, and the cross-sectional area inside the casing shoe d Otherwise, based on the total leakage, the depth of the inclination point, and the cross-sectional area of ​​the casing shoe, the bottom depth of the heavy slurry cap column H is calculated. d , that is, the injection position of the heavy slurry cap, which is calculated as follows:

[0050] When the casing shoe is located in the vertical well section, the H d The calculation method is:

[0051]

[0052] Among them, A c H is the inner cross-sectional area of ​​the casing shoe, c The depth of the well at the casing shoe;

[0053] When the casing shoe is not located in the vertical well section, the H d The calculation method is:

[0054]

[0055] Among them, A c H is the inner cross-sectional area of ​​the casing shoe, x The depth of the well at the inclination point.

[0056] Preferably, see Figure 4 , Figure 5 , the volume of the heavy grout cap in the drill string is calculated as follows:

[0057]

[0058] Among them, the P fa is the opening pressure of the one-way valve in the drilling tool, and A p is the cross-sectional area of ​​the drill string water hole.

[0059] Although the various steps in the above embodiment are described in the above-mentioned order, those skilled in the art can understand that in order to achieve the effect of this embodiment, different steps do not have to be executed in such an order. They can be executed simultaneously (in parallel) or in a reverse order. These simple changes are within the scope of protection of the present invention.

[0060] A second embodiment of the present invention is a system for designing a pressure-controlled drilling and well-killing heavy grouting cap for a lost formation, the system comprising:

[0061] A dynamic test module, configured to perform a pressure-controlled formation leakage dynamic test on the pull-out well, obtain dynamic test data, obtain bottom hole pressure based on the dynamic test data, and then obtain a bottom hole pressure-leakage rate relationship in combination with the dynamic data;

[0062] The first parameter calculation module obtains the set allowable original density drilling fluid loss rate Q p , and based on the Q p and the drilling operation time to calculate the total leakage; combined with the Q p and the bottom hole pressure-leakage rate relationship, calculate the maximum hydrostatic column pressure when injecting the heavy slurry cap;

[0063] The second parameter calculation module calculates the height of the liquid column of the heavy slurry cap according to the wellhead back pressure measured by the dynamic test data; and calculates the volume of the heavy slurry cap injected into the wellbore based on the height of the liquid column of the heavy slurry cap.

[0064] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process and related instructions of the system described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0065] It should be noted that the above embodiment provides a system for designing a heavy grouting cap for controlling the pressure of drilling and wellbore in a lost formation. It is only illustrated by the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the modules or steps in the embodiments of the present invention can be decomposed or combined. For example, the modules in the above embodiments can be combined into one module, or further divided into multiple sub-modules to complete all or part of the functions described above. The names of the modules and steps involved in the embodiments of the present invention are only for distinguishing the modules or steps, and are not regarded as improper limitations on the present invention.

[0066] See also Figure 6 A storage device according to a third embodiment of the present invention stores a plurality of programs, wherein the programs are suitable for being loaded and executed by a processor to implement a method for designing a heavy slurry cap for controlling the drilling pressure in a lost formation.

[0067] See also Figure 6 A processing device of the fourth embodiment of the present invention includes a processor and a storage device; the processor is suitable for executing various programs; the storage device is suitable for storing multiple programs; the program is suitable for being loaded and executed by the processor to implement a method for designing a heavy slurry cap for pressure-controlled drilling and wellbore pressure in a lost formation.

[0068] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process and related instructions of the storage device and processing device described above can refer to the corresponding process in the aforementioned method embodiment and will not be repeated here.

[0069] Those skilled in the art should be able to appreciate that the modules and method steps of each example described in conjunction with the embodiments disclosed herein can be implemented with electronic hardware, computer software or a combination of the two, and the programs corresponding to the software modules and method steps can be placed in random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium known in the technical field. In order to clearly illustrate the interchangeability of electronic hardware and software, the composition and steps of each example have been generally described in the above description according to the function. Whether these functions are performed in electronic hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0070] Reference below Figure 6 , which shows a schematic diagram of the structure of a computer system of a server for implementing the method, system, and device embodiments of the present application. Figure 6 The server shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0071] like Figure 6 As shown, the computer system includes a central processing unit (CPU) 601, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 602 or the program loaded from the storage part 608 to the random access memory (RAM) 603. Various programs and data required for system operation are also stored in the RAM 603. The CPU 601, ROM 602 and RAM 603 are connected to each other through a bus 604. An input / output (I / O) interface 605 is also connected to the bus 604.

[0072] The following components are connected to the I / O interface 605: an input section 606 including a keyboard, a mouse, etc.; an output section 607 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker; a storage section 608 including a hard disk, etc.; and a communication section 609 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 609 performs communication processing via a network such as the Internet. A drive 610 is also connected to the I / O interface 605 as needed. A removable medium 611, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 610 as needed so that a computer program read therefrom is installed into the storage section 608 as needed.

[0073] In particular, according to an embodiment of the present disclosure, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present disclosure includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through the communication part 609, and / or installed from the removable medium 611. When the computer program is executed by the central processing unit (CPU) 601, the above-mentioned functions defined in the method of the present application are executed. It should be noted that the above-mentioned computer-readable medium of the present application can be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium can be, for example, - but not limited to - an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to, an electrical connection with one or more conductors, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, an apparatus or a device. In the present application, a computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, which carries a computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in combination with an instruction execution system, an apparatus or a device. The program code contained on the computer-readable medium may be transmitted using any appropriate medium, including but not limited to: wireless, wire, optical cable, RF, etc., or any suitable combination of the above.

[0074] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0075] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0076] The terms "first", "second", etc. are used to distinguish similar objects rather than to describe or indicate a particular order or sequence.

[0077] The term "comprise" or any other similar term is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus / device that includes a list of elements includes not only those elements but also other elements not expressly listed, or also includes elements inherent to such process, method, article, or apparatus / device.

[0078] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A method for designing a heavy grouting cap for pressure-controlled drilling and well-killing in a lost formation, which is used to calculate the injection volume of the heavy grouting cap for drilling and well-killing and the maximum hydrostatic column pressure when the heavy grouting cap is injected, characterized in that: The method includes: Performing a pressure-controlled formation leakage dynamic test on the wellbore to obtain dynamic test data, obtaining bottom hole pressure based on the dynamic test data, and then obtaining a bottom hole pressure-leakage rate relationship in combination with the dynamic data; Get the set allowable original density drilling fluid loss rate Q p , and based on the Q p and the drilling operation time to calculate the total leakage; combined with the Q p and the bottom hole pressure-leakage rate relationship, calculate the maximum hydrostatic column pressure when injecting the heavy slurry cap; The height of the liquid column of the heavy slurry cap is calculated based on the wellhead back pressure measured by the dynamic test data; and the volume of the heavy slurry cap injected into the wellbore is calculated based on the height of the liquid column of the heavy slurry cap.

2. The method for designing a pressure-controlled drilling and well-killing heavy grouting cap for a lost formation according to claim 1, characterized in that: The dynamic test data is obtained by: Obtain the minimum wellhead back pressure P that can balance the invasion of formation fluid into the wellbore during drilling b , will be with the P b The corresponding leakage rate is recorded as Q loss ; Continuously reduce the mud pump drilling fluid flow rate into the well and increase the wellhead back pressure until the mud pump flow rate into the well is zero, and adjust the wellhead back pressure at this time to the leakage rate equal to the minimum wellhead back pressure P b Corresponding leakage rate Q loss , record the wellhead back pressure P at this time bq , the P bq As dynamic test data.

3. The method for designing a pressure-controlled drilling and well-killing heavy grouting cap for a lost formation according to claim 2, characterized in that: The bottom hole pressure P wb , and the method to obtain it is: P wb =P h +P bq Among them, the P h is the hydrostatic column pressure of the original density drilling fluid.

4. The method for designing a pressure-controlled drilling and well-killing heavy grouting cap for a lost formation according to claim 3, characterized in that: The bottom hole pressure-leakage rate relationship is obtained by: According to the P wb and the Q loss P is obtained by interpolation or fitting. wb =g(Q loss ) calculation model, wherein the calculation model is the bottom hole pressure-leakage rate relationship.

5. The method for designing a pressure-controlled drilling and well-killing heavy grouting cap for a lost formation according to claim 1, characterized in that: The total leakage amount is calculated as follows: V loss =T opt ×Q p ; Among them, the V loss is the total leakage volume, and Topt is the tripping time; The maximum hydrostatic column pressure when the heavy slurry cap is injected is calculated as follows: The Q p As Q loss , is brought into the calculation model of the bottom hole pressure-loss rate relationship, and the Q p The corresponding bottom hole pressure P wb ; According to the bottom hole pressure P wb and the hydrostatic column pressure P of the remaining slurry ho , calculate the maximum hydrostatic column pressure P when injecting heavy slurry cap hh : P wb =P hh +P ho 。 6. The method for designing a pressure-controlled drilling and well-killing heavy grouting cap for a lost formation according to claim 1, characterized in that: The liquid column height ΔH of the heavy slurry cap h , which is calculated as: P bq =ΔρgΔH h ; Wherein, the Δρ is the increase in the density of the heavy slurry cap compared to the original drilling fluid density.

7. A method for designing a pressure-controlled drilling and well-killing heavy grouting cap for a lost formation according to claim 6, characterized in that: The volume of the heavy slurry cap injected into the wellbore is calculated as follows: Among them, i is the corresponding number of the discrete unit in the wellbore space, ΔH is the discrete unit height of the heavy slurry cap in the wellbore, θ is the well inclination angle of the discrete unit, and A is the cross-sectional area of ​​the discrete unit.

8. A system for designing a pressure-controlled drilling and well-killing heavy grouting cap for a lost formation, based on a pressure-controlled drilling and well-killing heavy grouting cap design method for a lost formation according to any one of claims 1 to 7, characterized in that: The system includes: A dynamic test module, configured to perform a pressure-controlled formation leakage dynamic test on the pull-out well, obtain dynamic test data, obtain bottom hole pressure based on the dynamic test data, and further obtain a bottom hole pressure-leakage rate relationship in combination with the dynamic data; The first parameter calculation module obtains the set allowable original density drilling fluid loss rate Q p , and based on the Q p and the drilling operation time to calculate the total leakage; combined with the Q p and the bottom hole pressure-leakage rate relationship, calculate the maximum hydrostatic column pressure when injecting the heavy slurry cap; The second parameter calculation module calculates the height of the liquid column of the heavy slurry cap according to the wellhead back pressure measured by the dynamic test data; and calculates the volume of the heavy slurry cap injected into the wellbore based on the height of the liquid column of the heavy slurry cap.

9. A storage device storing a plurality of programs, characterized in that: The program is suitable for being loaded and executed by a processor to implement a method for designing a pressure-controlled drilling and well-killing heavy grouting cap for a lost formation as described in any one of claims 1 to 7.

10. A processing device, comprising a processor and a storage device; the processor is adapted to execute each program; the storage device is adapted to store a plurality of programs; characterized in that: The program is suitable for being loaded and executed by a processor to implement a method for designing a pressure-controlled drilling and well-killing heavy grouting cap for a lost formation as described in any one of claims 1 to 7.

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