A high-temperature high-pressure large displacement well production pipe string safety evaluation system and evaluation method

Abstract

The application discloses a high-temperature high-pressure large displacement well production pipe column safety evaluation system and an evaluation method. The high-temperature high-pressure large displacement well production pipe column safety evaluation system comprises a fluid circulation pipeline, a cooling tank, a mud pool, a heating tank, a pressurizing device, a wellbore experiment module, a load loading module, a strain measuring device, a temperature and pressure collecting module, a flow pump module, a one-way valve module and a control and data collection module. The control and data collection module is electrically connected with the cooling tank, the heating tank, the mud pool, the pressurizing device, the wellbore experiment module, the load loading module, the strain measuring device, the temperature and pressure collecting module, the flow pump module and the one-way valve module, and can collect temperature, pressure and pipe column strain data in a real-time manner during an experiment process. The load loading module is used for controlling the experiment process of the pipe column, and the flow pump module and the one-way valve module are used for starting or stopping and opening or closing to realize fluid circulation. The application can accurately evaluate the safety state of the large displacement well production pipe column.

Description

Technical Field

[0001] This invention relates to the field of oil and gas drilling and production technology, and in particular to a safety evaluation system and method for production tubing in high-temperature, high-pressure, and extended-reach wells. Background Technology

[0002] As global oil and gas exploration and development expands into deeper and more complex formations, extended reach wells, as a key technology for the efficient development of complex oil and gas reservoirs, are seeing their application scale continuously expand. Extended reach wells often face extreme conditions such as high temperature and high pressure during production, posing a severe challenge to the structural integrity of the production tubing.

[0003] Under the combined effects of high temperature and high pressure, production tubing, due to its low stiffness and large deflection, is prone to significant bending deformation under the influence of the wellbore trajectory, which can lead to structural instability or even failure, seriously affecting the safe production and long-term operation of oil and gas wells. Currently, research on the structural safety evaluation of downhole tubing mainly focuses on numerical simulation methods, primarily addressing the risk of obstruction during tubing installation and failure caused by external pressure. However, systematic research on the ultimate structural strength of tubing under high temperature and high pressure conditions is insufficient, and relevant experimental testing equipment is also lacking, making it difficult to comprehensively assess the safety status of production tubing in extended reach wells in actual service environments.

[0004] Therefore, developing a safety evaluation system and method for production tubing that can simulate extreme working conditions of high temperature and high pressure and simultaneously apply multiple complex loads such as tension, compression, bending and torsion has important engineering application value and scientific research significance. Summary of the Invention

[0005] This invention provides a safety evaluation system and method for production tubing in high-temperature and high-pressure extended reach wells. This addresses the problem in the prior art of lacking an experimental device for safety evaluation of production tubing in extended reach wells that can simulate the complex load coupling effects under high-temperature and high-pressure environments, which makes it difficult to comprehensively and accurately assess the structural integrity and failure behavior of the production tubing under actual service conditions. This invention aims to achieve an accurate assessment of the safety status of production tubing in extended reach wells.

[0006] According to one aspect of the present invention, a safety evaluation system for production tubing in high-temperature and high-pressure extended reach wells is provided. The safety evaluation system for production tubing in high-temperature and high-pressure extended reach wells includes: a fluid circulation pipeline, a cooling tank, a mud tank, a heating tank, a pressurization device, a wellbore test module, a load loading module, a strain measurement device, a temperature and pressure acquisition module, a transfer pump module, a check valve module, and a control and data collection module. The cooling tank, the heating tank, the mud tank, and the pressurizing device are connected to the wellbore test module via the fluid circulation pipeline. The transfer pump module and the one-way valve module are sequentially arranged on the fluid circulation pipeline. The fluid circulation pipeline is used to circulate the fluid. The heating tank is used to heat the fluid in the fluid circulation pipeline. The cooling tank is used to cool the fluid in the fluid circulation pipeline. The pressurizing device is used to pressurize the wellbore cavity in the wellbore test module. The mud tank is used for mud preparation, fluid circulation, and waste liquid recovery. The wellbore test module is used to house and fix the tubing to be tested, and to conduct an ultimate strength test on the tubing; the load loading module is located at both ends of the wellbore test module, and is used to apply mechanical loads to the tubing inside the wellbore test module; the strain measuring device is attached to the surface of the tubing, and is used to measure the strain of the tubing and transmit the strain data to the control and data collection module. The temperature and pressure acquisition module is sequentially installed on the cooling tank, the heating tank, the pressurizing device, and the well shaft experimental module, and is used to collect temperature and pressure data at various points during the experiment and transmit them to the control and data collection module. The control and data collection module is electrically connected to the cooling tank, the heating tank, the mud tank, the pressurization device, the wellbore experiment module, the load loading module, the strain measurement device, the temperature and pressure acquisition module, the flow pump module, and the one-way valve module, respectively. It is used to collect temperature, pressure, and tubing strain data in real time during the experiment. The load loading module controls the experimental process of the tubing, and the flow pump module is started or stopped, and the one-way valve module is opened or closed to achieve fluid circulation.

[0007] Optionally, the temperature and pressure acquisition module includes: a first temperature and pressure instrument, a second temperature and pressure instrument, a third temperature and pressure instrument, and a fourth temperature and pressure instrument; The first temperature and pressure gauge, the second temperature and pressure gauge, the third temperature and pressure gauge, and the fourth temperature and pressure gauge are sequentially installed on the cooling tank, the heating tank, the pressurizing device, and the wellbore experimental module, and are used to collect the temperature and pressure data of the cooling tank, the heating tank, the pressurizing device, and the wellbore experimental module during the experiment and transmit them to the control and data collection module.

[0008] Optionally, the pump module includes: a first pump, a second pump, a third pump, a fourth pump, and a fifth pump; The first pump is installed on the fluid circulation pipeline between the cooling tank and the mud tank; the second pump is installed on the fluid circulation pipeline between the heating tank and the load loading module; the third pump is installed on the fluid circulation pipeline between the wellbore test module and the pressurization device; the fourth pump is installed on the fluid circulation pipeline between the wellbore test module and the cooling tank; and the fifth pump is installed on the fluid circulation pipeline between the wellbore test module and the heating tank.

[0009] Optionally, the one-way valve module includes: a first one-way valve, a second one-way valve, a third one-way valve, a fourth one-way valve, and a fifth one-way valve; The first check valve is installed on the fluid circulation pipeline between the mud tank and the heating tank; the second check valve is installed on the fluid circulation pipeline between the heating tank and the load loading module; the third check valve is installed on the fluid circulation pipeline between the wellbore test module and the heating tank and the cooling tank; the fourth check valve is installed on the fluid circulation pipeline between the wellbore test module and the cooling tank; and the fifth check valve is installed on the fluid circulation pipeline between the wellbore test module and the heating tank.

[0010] Optionally, the load loading module includes: an upper load loading device and a lower load loading device; The upper load loading device is located above the wellbore test module and connected to the top of the tubing string. The lower load loading device is located below the wellbore test module and connected to the bottom of the tubing string. The upper load loading device and the lower load loading device each independently include a shaft and a two-part coupling.

[0011] Optionally, the wellbore experimental module includes: a wellbore-tubing assembly structure, which includes: a wellbore section, a tubing section, a connecting structure, and a sealing structure; The wellbore section includes: an upper sealing device, a vertical section of the wellbore, an upper wellbore reducing joint, a curved section of the wellbore, a lower wellbore reducing joint, and a horizontal section of the wellbore, connected in sequence. The tubing section includes: a vertical tubing section, an upper tubing reducer joint, a curved tubing section, a lower tubing reducer joint, and a horizontal tubing section, all disposed inside the wellbore section. The communication structure includes: a fluid circulation hole disposed on the horizontal section of the tubing string for connecting the internal channel of the tubing string with the internal channel of the wellbore; The sealing structure includes a lower sealing device disposed at the bottom of the wellbore portion.

[0012] Optionally, the upper wellbore reducing joint and the lower wellbore reducing joint are used to replace wellbore sections of different sizes; The upper and lower tubing reducer joints are used to replace tubing sections of different sizes.

[0013] Optionally, the safety evaluation system for production tubing in high-temperature, high-pressure, and extended-reach wells also includes: a power module; The power module is connected to the heating tank, the cooling tank, and the control and data collection module, and the power module is used to provide power to the heating tank, the cooling tank, and the control and data collection module.

[0014] Optionally, the strain measuring device consists of a high-temperature and high-pressure strain gauge.

[0015] According to another aspect of the present invention, a method for safety evaluation of production tubing in high-temperature, high-pressure, and extended-reach wells is provided, which is executed by the high-temperature, high-pressure, and extended-reach well production tubing safety evaluation system described in any one of the preceding aspects, the method comprising: The control and data collection module starts the pump module and the check valve module to circulate the fluid, and opens the heating tank to heat the fluid to the target temperature and then circulate it into the wellbore test module until the temperature inside the wellbore in the wellbore test module reaches the experimental requirements. By controlling the control and data collection module to shut down the transfer pump module and the check valve module to close the fluid circulation, the pressurizing device pressurizes the inside of the wellbore in the wellbore experimental module until the pressure inside the wellbore reaches the experimental requirements. The load loading module applies at least one load to the production string to be tested in the wellbore test module, and the strain measurement device monitors the strain change of the string in the wellbore test module, transmitting the strain data to the control and data collection module. After the experiment, the control and data collection module starts the pump module and the check valve module, opens the fluid circulation pipeline, and allows the high-temperature and high-pressure fluid to enter the cooling tank for cooling. The cooled fluid is then discharged into the mud pool for waste liquid treatment.

[0016] The technical solution of this invention can simultaneously simulate high-temperature and high-pressure environments and independently apply multiple mechanical loads such as tension, compression, bending, and torsion. It effectively simulates the full-condition failure behavior of a large-displacement well production tubing system under complex load coupling conditions, overcoming the deficiency of existing devices that can only simulate a single condition. It employs a control center to uniformly control all transfer pumps, valves, and load loading modules, and collects temperature, pressure, and strain data in real time, achieving a high degree of automation in the experimental process and high accuracy in measurement results. This solves the problem in existing technologies of lacking a safety evaluation experimental device for large-displacement well production tubing under complex load coupling conditions, which makes it difficult to comprehensively and accurately assess the structural integrity and failure behavior of the production tubing under actual service conditions. It effectively simulates the full-condition failure behavior of a large-displacement well production tubing system under complex load coupling conditions. Furthermore, it utilizes a control center for intelligent experiments, achieving the beneficial effect of accurately assessing and verifying the safety status of large-displacement well production tubing.

[0017] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of a safety evaluation system for production tubing in high-temperature, high-pressure, and extended-displacement wells provided in an embodiment of the present invention. Figure 2 This is a flowchart of a method for safety evaluation of production tubing in high-temperature, high-pressure, and large-displacement wells provided in an embodiment of the present invention. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0021] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0022] Figure 1 This is a schematic diagram of a safety evaluation system for production tubing in high-temperature, high-pressure, and extended-reach wells provided in an embodiment of the present invention. (Refer to...) Figure 1 The present invention provides a safety evaluation system for production tubing in high-temperature and high-pressure extended reach wells. The safety evaluation system for production tubing in high-temperature and high-pressure extended reach wells includes: a fluid circulation pipeline, a cooling tank 1, a mud tank 4, a heating tank 6, a pressurization device 16, a wellbore test module, a load loading module, a strain measurement device 28, a temperature and pressure acquisition module, a transfer pump module, a one-way valve module, and a control and data collection module 26. Cooling tank 1, heating tank 6, mud tank 4, and pressurizing device 16 are connected to the wellbore test module through a fluid circulation pipeline. The transfer pump module and the one-way valve module are sequentially installed on the fluid circulation pipeline. The fluid circulation pipeline is used to realize the circulation of fluid. Heating tank 6 is used to heat the fluid in the fluid circulation pipeline. Cooling tank 1 is used to cool the fluid in the fluid circulation pipeline. Pressurizing device 16 is used to pressurize the wellbore cavity in the wellbore test module. Mud tank 4 is used for mud preparation, fluid circulation, and waste liquid recovery. The wellbore test module is used to house and fix the tubing to be tested, and to conduct ultimate strength tests on the tubing; the load loading module is set at both ends of the wellbore test module to apply mechanical loads to the tubing inside the wellbore test module; the strain measurement device 28 is attached to the surface of the tubing to measure the strain of the tubing and transmit the strain data to the control and data collection module 26. Temperature and pressure acquisition modules are sequentially installed on cooling tank 1, heating tank 6, pressurizing device 16 and well shaft experimental module to collect temperature and pressure data at various points during the experiment and transmit them to control and data collection module 26. The control and data collection module 26 is electrically connected to the cooling tank 1, heating tank 6, mud tank 4, pressurization device 16, wellbore test module, load loading module, strain measurement device 28, temperature and pressure acquisition module, transfer pump module, and one-way valve module, respectively. It is used to collect temperature, pressure and tubing strain data in real time during the experiment. The load loading module controls the experimental process of the tubing, and the transfer pump module starts or stops, and the one-way valve module opens or closes to achieve fluid circulation.

[0023] Specifically, cooling tank 1 is mainly used for fluid cooling after the experiment, while mud tank 4 is mainly used for slurry preparation, fluid circulation, and waste liquid recovery. Cooling tank 1 and heating tank 6 are made of high-temperature and high-pressure resistant materials. Pressurization device 16 can be a high-pressure gas tank, mainly used for pressurization. Through heating tank 6, cooling tank 1, mud tank 4, and high-pressure gas tank, a high-temperature and high-pressure downhole working environment, as well as fluid cooling and waste liquid recovery after the experiment, can be achieved.

[0024] The wellbore-tubing assembly is primarily used to simulate the service life of production tubing in extended reach wells. The load loading module includes an upper load loading device 11 and a lower load loading device 21, composed of shafts and split couplings, and is mainly used to apply complex loads to the experimental tubing. The strain measurement device 28 consists of high-temperature, high-pressure strain gauges and primarily functions for strain detection. The fluid circulation pipeline and pressure vessel possess excellent sealing properties.

[0025] The working process of the fluid circulation and temperature control loop is as follows: The experimental fluids in cooling tank 1 and mud tank 4 enter heating tank 6 via the first transfer pump 3 and the first one-way valve 5, respectively. Heating tank 6 (equipped with a second temperature and pressure gauge 7) heats the fluid. The heated fluid then enters the tubing through the internal channel of the upper load loading device 11 via the second transfer pump 8 and the second one-way valve 9. The fluid returns to cooling tank 1 via the fourth transfer pump 22 and the fourth one-way valve 24, or enters heating tank 6 via the fifth transfer pump 23 and the fifth one-way valve 25. Cooling tank 1 (equipped with a first temperature and pressure gauge 2) is used to cool the fluid after the experiment.

[0026] The pressurization device 16 (equipped with a third temperature and pressure gauge 17) is connected to the wellbore test module via a third transfer pump 15 and a third one-way valve 10, and is used to apply high pressure to the inside of the wellbore. The upper load loading device 11 and the lower load loading device 21 are respectively connected to the upper and lower ends of the tubing string, each consisting of a free shaft and a two-part coupling, and can independently or collaboratively apply tensile, compressive, bending, torsional, and combined loads.

[0027] The strain measurement device 28 is attached to key locations on the tubing (such as bends and reducers), and its signal cable is sealed and led out to the control and data acquisition module 26. The control and data acquisition module 26, based on a computer, is connected to all the pumps, check valves, load loading devices, temperature and pressure gauges, and strain measurement devices. It is used to send control commands and receive, store, and display all experimental data.

[0028] The control and data collection module 26 serves as the control center, with a computer as its main component, connected to various instruments. It is primarily used to control the instruments and collect data, achieving intelligent control. Multiple temperature and pressure gauges, heating tank 6, cooling tank 1, multiple transfer pumps, multiple check valves, and strain measurement device 28 are all controlled by the control center. The control center can receive and transmit data, enabling precise control and accurate measurement.

[0029] For example, the temperature and pressure acquisition module can consist of multiple temperature and pressure gauges (first temperature and pressure gauge 2, second temperature and pressure gauge 7, third temperature and pressure gauge 17, and fourth temperature and pressure gauge 30), and has real-time measurement and data transmission capabilities. The transfer pump module consists of multiple transfer pumps (first transfer pump 3, second transfer pump 8, third transfer pump 15, fourth transfer pump 22, and fifth transfer pump 23). The check valve module consists of multiple check valves (first check valve 5, second check valve 9, third check valve 10, fourth check valve 24, and fifth check valve 25).

[0030] The wellbore test module includes: upper sealing device 13, vertical section wellbore 14, upper wellbore reducing joint 29, curved section wellbore 18, lower wellbore reducing joint 32, horizontal section wellbore 19, vertical section tubing 12, upper tubing reducing joint 27, curved section tubing 31, lower tubing reducing joint 33, horizontal section tubing 34, fluid circulation hole 35, and lower sealing device 20.

[0031] The specific workflow of the high-temperature, high-pressure, extended reach well production tubing safety evaluation system is as follows: the control and data collection module 26 issues an instruction, and the fluid enters the heating tank 6 through the mud tank 4 for heating. After reaching the experimental temperature, it is transported to the vertical section tubing 12 through the second transfer pump 8, and then enters the wellbore (vertical section wellbore 14, curved section wellbore 18, and horizontal section wellbore 19) through the fluid circulation hole 35. It then re-enters the heating tank 6 through the fluid circulation pipeline between the vertical section wellbore 14 and the heating tank 6, thus realizing high-temperature liquid circulation. Once the temperature inside the wellbore reaches the experimental requirements, the high-temperature liquid circulation pipeline is closed, and the pressurization device 16 is opened to pressurize the inside of the wellbore until the internal pressure reaches the experimental requirements. Then, the pressurization device 16 is closed, and tensile, compressive, bending, and torsional loads are applied to the vertical section tubing 12, the curved section tubing 31, and the horizontal section tubing 34 through the upper load loading device 11 and the lower load loading device 21. The strain changes of the vertical section tubing 12, the curved section tubing 31, and the horizontal section tubing 34 are monitored by the strain measurement device 28, and the data is transmitted to the control and data collection module 26 through the transmission cable. After the experiment, the fluid circulation pipeline between the vertical section wellbore 14 and the cooling tank 1 is opened to allow the high-temperature and high-pressure fluid to enter the cooling tank 1. After cooling, the fluid is discharged into the mud tank 4 for waste liquid treatment.

[0032] Existing experimental setups can only simulate failure behavior under single operating conditions. This invention can effectively simulate the failure behavior of extended reach well production tubing systems under complex load coupling conditions, enabling accurate assessment and verification of the safety status of extended reach well production tubing. This invention utilizes a control center for intelligent experimentation to achieve accurate assessment and verification of the safety status of extended reach well production tubing.

[0033] The technical solution of this invention can simultaneously simulate high-temperature and high-pressure environments and independently apply multiple mechanical loads such as tension, compression, bending, and torsion. It effectively simulates the full-condition failure behavior of a large-displacement well production tubing system under complex load coupling conditions, overcoming the deficiency of existing devices that can only simulate a single condition. It employs a control center to uniformly control all transfer pumps, valves, and load loading modules, and collects temperature, pressure, and strain data in real time, achieving a high degree of automation in the experimental process and high accuracy in measurement results. This solves the problem in existing technologies of lacking a safety evaluation experimental device for large-displacement well production tubing under complex load coupling conditions, which makes it difficult to comprehensively and accurately assess the structural integrity and failure behavior of the production tubing under actual service conditions. It effectively simulates the full-condition failure behavior of a large-displacement well production tubing system under complex load coupling conditions. Furthermore, it utilizes a control center for intelligent experiments, achieving the beneficial effect of accurately assessing and verifying the safety status of large-displacement well production tubing.

[0034] Continue to refer to Figure 1Optionally, the temperature and pressure acquisition module includes: a first temperature and pressure instrument 2, a second temperature and pressure instrument 7, a third temperature and pressure instrument 17, and a fourth temperature and pressure instrument 30. The first temperature and pressure instrument 2, the second temperature and pressure instrument 7, the third temperature and pressure instrument 17, and the fourth temperature and pressure instrument 30 are sequentially installed on the cooling tank 1, the heating tank 6, the pressurizing device 16, and the well shaft experimental module. They are used to collect the temperature and pressure data of the cooling tank 1, the heating tank 6, the pressurizing device 16, and the well shaft experimental module during the experiment and transmit them to the control and data collection module 26.

[0035] Specifically, the fourth temperature and pressure gauge 30 is installed on the wellbore to monitor the actual temperature and pressure inside the test chamber.

[0036] Continue to refer to Figure 1 Optionally, the pump module includes: a first pump 2, a second pump 8, a third pump 15, a fourth pump 22, and a fifth pump 23; The first pump 2 is installed on the fluid circulation pipeline between the cooling tank 1 and the mud tank 4; the second pump 8 is installed on the fluid circulation pipeline between the heating tank 6 and the load loading module; the third pump 15 is installed on the fluid circulation pipeline between the wellbore test module and the pressurization device 16; the fourth pump 22 is installed on the fluid circulation pipeline between the wellbore test module and the cooling tank 1; and the fifth pump 23 is installed on the fluid circulation pipeline between the wellbore test module and the heating tank 6.

[0037] Continue to refer to Figure 1 Optionally, the check valve module includes: a first check valve 5, a second check valve 9, a third check valve 10, a fourth check valve 24, and a fifth check valve 25; The first one-way valve 5 is installed on the fluid circulation pipeline between the mud tank 4 and the heating tank 6; the second one-way valve 9 is installed on the fluid circulation pipeline between the heating tank 6 and the load loading module; the third one-way valve 10 is installed on the fluid circulation pipeline between the wellbore test module and the heating tank 6 and the cooling tank 1; the fourth one-way valve 24 is installed on the fluid circulation pipeline between the wellbore test module and the cooling tank 1; and the fifth one-way valve 25 is installed on the fluid circulation pipeline between the wellbore test module and the heating tank 6.

[0038] Continue to refer to Figure 1 Optionally, the load loading module includes: an upper load loading device 11 and a lower load loading device 21; The upper load loading device 11 is located above the wellbore test module and connected to the top of the tubing string. The lower load loading device 21 is located below the wellbore test module and connected to the bottom of the tubing string. The upper load loading device 11 and the lower load loading device 21 each independently include a shaft and a two-part coupling.

[0039] Specifically, the upper load loading device 11 and the lower load loading device 21 can be used to simulate the deformation of the tubing under complex load coupling under actual working conditions.

[0040] Continue to refer to Figure 1 Optionally, the wellbore test module includes: a wellbore-tubing assembly structure, which includes: a wellbore section, a tubing section, a connecting structure, and a sealing structure; The wellbore section includes: an upper sealing device 13, a vertical section wellbore 14, an upper wellbore reducing joint 29, a curved section wellbore 18, a lower wellbore reducing joint 32, and a horizontal section wellbore 19, which are connected in sequence. The tubing section includes: a vertical section tubing 12 installed inside the wellbore section, an upper tubing reducer joint 27, a curved section tubing 31, a lower tubing reducer joint 33, and a horizontal section tubing 34. The connecting structure includes: a fluid circulation hole 35 provided on the horizontal section of the tubing string 34, for connecting the internal channel of the tubing string with the internal channel of the wellbore; The sealing structure includes a lower sealing device 20 located at the bottom of the wellbore section.

[0041] Specifically, the wellbore-tubing assembly is the core carrier of the experiment, consisting of an upper sealing device 13, a vertical wellbore section 14, an upper wellbore reducing joint 29, a curved wellbore section 18, a lower wellbore reducing joint 32, a horizontal wellbore section 19, a vertical tubing section 14, an upper tubing reducing joint 27, a curved tubing section 31, a lower tubing reducing joint 33, a horizontal tubing section 34, a fluid circulation hole 35, and a lower sealing device 20. Through the reducing joints of the upper and lower wellbore and tubing, experiments can be conducted using wellbore and tubing assemblies of different sizes. The fluid circulation hole 35 serves to connect the internal channels of the tubing and the internal channels of the wellbore.

[0042] Continue to refer to Figure 1 Optionally, the upper wellbore reducing joint 29 and the lower wellbore reducing joint 32 are used to replace wellbore sections of different sizes; The upper tubing reducer 27 and the lower tubing reducer 33 are used to replace tubing sections of different sizes.

[0043] Specifically, by using wellbore reducing joints and tubing reducing joints, wellbore sections and tubing sections of different sizes can be flexibly replaced, enabling safety evaluation of different specifications of production tubing combinations, and has a wide range of applications.

[0044] Optionally, the safety evaluation system for production tubing in high-temperature, high-pressure, and extended-reach wells also includes: a power module; The power module is connected to the heating tank, cooling tank, and control and data collection module, and is used to provide power to the heating tank, cooling tank, and control and data collection module.

[0045] Continue to refer to Figure 1 Optionally, the strain measuring device 28 consists of high-temperature and high-pressure strain gauges.

[0046] Specifically, a control center is adopted to achieve high-precision and intelligent experiments. The strain measurement device 28 adopts a high-temperature and high-pressure resistant strain gauge combination structure and is connected to the control center to achieve normal operation and real-time monitoring in high-temperature and high-pressure environments.

[0047] Figure 2 This is a flowchart of a safety evaluation method for production tubing in high-temperature, high-pressure, extended reach wells provided by an embodiment of the present invention. This embodiment effectively simulates the full-condition failure behavior of a production tubing system in extended reach wells under complex load coupling conditions. This method can be executed by a safety evaluation system for production tubing in high-temperature, high-pressure, extended reach wells. Figure 2 As shown, the method includes: S110. The flow pump module and check valve module are started through the control and data collection module to circulate the fluid, and the heating tank is turned on to heat the fluid to the target temperature and then circulate it into the well test module until the temperature inside the well reaches the experimental requirements.

[0048] Specifically, in combination Figure 1 Step 1: Establishing the High-Temperature Environment. The operator issues commands through the control and data collection module 26. The second transfer pump 8 is started, and the first one-way valve 5 and the second one-way valve 9 are opened. Fluid in the mud tank 4 enters the heating tank 6 through the first one-way valve 5. The heating tank 6 starts, heating the fluid to the preset experimental temperature (e.g., 150℃). The high-temperature fluid enters the tubing cavity through the second transfer pump 8 and the upper load loading device 11, flowing through the vertical section of the tubing 14, the curved section of the tubing 31, and the horizontal section of the tubing 34, before entering the wellbore annulus through the fluid circulation hole 35. It then returns to the heating tank 6 via the fifth transfer pump 23, forming a circulation. When the heated liquid is pumped into the tubing, heat dissipation occurs through the pipeline, and the temperature inside the tubing is insufficient. A single circulation is initiated, circulating only between the heating tank 6 and the tubing. The fourth temperature and pressure instrument 30 monitors the wellbore temperature in real time. When the required experimental temperature is reached, the control and data collection module 26 shuts down the relevant pumps and valves, stopping the circulation.

[0049] S120. By controlling the control and data collection module, the flow pump module and the one-way valve module are shut down to close the fluid circulation. The wellbore inside the wellbore test module is pressurized by the pressurizing device until the pressure inside the wellbore reaches the experimental requirements.

[0050] Specifically, in combination Figure 1Step 2: Establishing the high-pressure environment. The control and data collection module 26 opens the third check valve 10 and starts the third transfer pump 15. The high-pressure gas in the pressurization device 16 (or through gas-liquid pressurization) pressurizes the sealed wellbore annulus. The third temperature and pressure instrument 17 and the fourth temperature and pressure instrument 30 monitor the pressure in real time. When the required experimental pressure (e.g., 100 MPa) is reached, the third check valve 10 and the third transfer pump 15 are closed.

[0051] S130. Apply at least one load to the production string to be tested in the wellbore test module through the load loading module, monitor the strain change of the string in the wellbore test module through the strain measurement device, and transmit the strain data to the control and data collection module.

[0052] Specifically, in combination Figure 1 The third step: Complex load application and data acquisition. Under the premise of maintaining a high-temperature, high-pressure static environment, the control and data acquisition module 26 instructs the upper load application device 11 and / or the lower load application device 21 to apply one or more loads of tension, compression, bending, and torsion to the tubing according to a preset loading spectrum. Simultaneously, the strain measurement device 28 acquires the strain signal on the tubing surface in real time and transmits the data to the control and data acquisition module 26 via a transmission cable. The control and data acquisition module 26 synchronously records the load magnitude, temperature, pressure, and strain data for subsequent analysis of the tubing's strength and failure behavior.

[0053] S140. After the experiment, the flow pump module and check valve module are started through the control and data collection module to open the fluid circulation pipeline, so that the high temperature and high pressure fluid enters the cooling tank for cooling, and the cooled fluid is discharged into the mud pool for waste liquid treatment.

[0054] Specifically, in combination Figure 1 Step 4: Post-experiment processing. After the experiment, the control and data collection module 26 instructs the fourth check valve 24 to open and the fourth transfer pump 22 to start. The high-temperature and high-pressure fluid in the wellbore and pipeline returns to the cooling tank 1 via the fourth transfer pump 22 and the fourth check valve 24, where it is cooled. Finally, the cooled fluid is discharged into the mud tank 4 via the first transfer pump 3 for environmental treatment or recycling. After the experiment, the high-temperature and high-pressure fluid is cooled by the cooling tank 1 and then discharged into the mud tank 4 for waste liquid recycling, meeting safety and environmental protection requirements.

[0055] Through the above system and method, the present invention can realistically simulate the service status of production tubing in extended reach wells under the coupled action of high temperature, high pressure and complex mechanical loads, providing a reliable experimental platform for the structural integrity design and safety assessment of production tubing.

[0056] The safety evaluation method for production tubing in high-temperature, high-pressure, and extended reach wells provided in this embodiment of the invention is executed by the safety evaluation system for production tubing in high-temperature, high-pressure, and extended reach wells provided in this embodiment of the invention. Therefore, the beneficial effects of the safety evaluation method for production tubing in high-temperature, high-pressure, and extended reach wells and the safety evaluation system for production tubing in high-temperature, high-pressure, and extended reach wells are the same, and will not be repeated here.

[0057] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A safety evaluation system for production tubing in high-temperature, high-pressure, long-reach wells, characterized in that, include: Fluid circulation pipeline, cooling tank, mud tank, heating tank, pressurization device, wellbore test module, load loading module, strain measurement device, temperature and pressure acquisition module, transfer pump module, one-way valve module, and control and data collection module; The cooling tank, the heating tank, the mud tank, and the pressurizing device are connected to the wellbore test module via the fluid circulation pipeline. The transfer pump module and the one-way valve module are sequentially arranged on the fluid circulation pipeline. The fluid circulation pipeline is used to circulate the fluid. The heating tank is used to heat the fluid in the fluid circulation pipeline. The cooling tank is used to cool the fluid in the fluid circulation pipeline. The pressurizing device is used to pressurize the wellbore cavity in the wellbore test module. The mud tank is used for mud preparation, fluid circulation, and waste liquid recovery. The wellbore test module is used to house and fix the tubing to be tested, and to conduct an ultimate strength test on the tubing; the load loading module is located at both ends of the wellbore test module, and is used to apply mechanical loads to the tubing inside the wellbore test module; the strain measuring device is attached to the surface of the tubing, and is used to measure the strain of the tubing and transmit the strain data to the control and data collection module. The temperature and pressure acquisition module is sequentially installed on the cooling tank, the heating tank, the pressurizing device, and the well shaft experimental module, and is used to collect temperature and pressure data at various points during the experiment and transmit them to the control and data collection module. The control and data collection module is electrically connected to the cooling tank, the heating tank, the mud tank, the pressurization device, the wellbore experiment module, the load loading module, the strain measurement device, the temperature and pressure acquisition module, the flow pump module, and the one-way valve module, respectively. It is used to collect temperature, pressure, and tubing strain data in real time during the experiment. The load loading module controls the experimental process of the tubing, and the flow pump module is started or stopped, and the one-way valve module is opened or closed to achieve fluid circulation.

2. The system according to claim 1, characterized in that, The temperature and pressure acquisition module includes: a first temperature and pressure instrument, a second temperature and pressure instrument, a third temperature and pressure instrument, and a fourth temperature and pressure instrument; The first temperature and pressure gauge, the second temperature and pressure gauge, the third temperature and pressure gauge, and the fourth temperature and pressure gauge are sequentially installed on the cooling tank, the heating tank, the pressurizing device, and the wellbore experimental module, and are used to collect the temperature and pressure data of the cooling tank, the heating tank, the pressurizing device, and the wellbore experimental module during the experiment and transmit them to the control and data collection module.

3. The system according to claim 1, characterized in that, The pump module includes: a first pump, a second pump, a third pump, a fourth pump, and a fifth pump; The first pump is installed on the fluid circulation pipeline between the cooling tank and the mud tank; the second pump is installed on the fluid circulation pipeline between the heating tank and the load loading module; the third pump is installed on the fluid circulation pipeline between the wellbore test module and the pressurization device; the fourth pump is installed on the fluid circulation pipeline between the wellbore test module and the cooling tank; and the fifth pump is installed on the fluid circulation pipeline between the wellbore test module and the heating tank.

4. The system according to claim 1, characterized in that, The one-way valve module includes: a first one-way valve, a second one-way valve, a third one-way valve, a fourth one-way valve, and a fifth one-way valve; The first check valve is installed on the fluid circulation pipeline between the mud tank and the heating tank; the second check valve is installed on the fluid circulation pipeline between the heating tank and the load loading module; the third check valve is installed on the fluid circulation pipeline between the wellbore test module and the heating tank and the cooling tank; the fourth check valve is installed on the fluid circulation pipeline between the wellbore test module and the cooling tank; and the fifth check valve is installed on the fluid circulation pipeline between the wellbore test module and the heating tank.

5. The system according to claim 1, characterized in that, The load loading module includes: an upper load loading device and a lower load loading device; The upper load loading device is located above the wellbore test module and connected to the top of the tubing string. The lower load loading device is located below the wellbore test module and connected to the bottom of the tubing string. The upper load loading device and the lower load loading device each independently include a shaft and a two-part coupling.

6. The system according to claim 1, characterized in that, The wellbore experimental module includes a wellbore-tubing assembly structure, which includes a wellbore section, a tubing section, a connecting structure, and a sealing structure. The wellbore section includes: an upper sealing device, a vertical section of the wellbore, an upper wellbore reducing joint, a curved section of the wellbore, a lower wellbore reducing joint, and a horizontal section of the wellbore, connected in sequence. The tubing section includes: a vertical tubing section, an upper tubing reducer joint, a curved tubing section, a lower tubing reducer joint, and a horizontal tubing section, all disposed inside the wellbore section. The communication structure includes: a fluid circulation hole disposed on the horizontal section of the tubing string for connecting the internal channel of the tubing string with the internal channel of the wellbore; The sealing structure includes a lower sealing device disposed at the bottom of the wellbore portion.

7. The system according to claim 6, characterized in that, The upper wellbore reducing joint and the lower wellbore reducing joint are used to replace wellbore sections of different sizes; The upper and lower tubing reducer joints are used to replace tubing sections of different sizes.

8. The system according to claim 1, characterized in that, Also includes: Power module; The power module is connected to the heating tank, the cooling tank, and the control and data collection module, and the power module is used to provide power to the heating tank, the cooling tank, and the control and data collection module.

9. The system according to claim 1, characterized in that, The strain measurement device consists of high-temperature and high-pressure strain gauges.

10. A method for safety evaluation of production tubing in high-temperature, high-pressure, long-reach wells, characterized in that, The method, performed by the high-temperature, high-pressure, extended reach well production tubing safety evaluation system according to any one of claims 1-9, comprises: The control and data collection module starts the pump module and the check valve module to circulate the fluid, and opens the heating tank to heat the fluid to the target temperature and then circulate it into the wellbore test module until the temperature inside the wellbore in the wellbore test module reaches the experimental requirements. By controlling the control and data collection module to shut down the transfer pump module and the check valve module to close the fluid circulation, the pressurizing device pressurizes the inside of the wellbore in the wellbore experimental module until the pressure inside the wellbore reaches the experimental requirements. The load loading module applies at least one load to the production string to be tested in the wellbore test module, and the strain measurement device monitors the strain change of the string in the wellbore test module, transmitting the strain data to the control and data collection module. After the experiment, the control and data collection module starts the pump module and the check valve module, opens the fluid circulation pipeline, and allows the high-temperature and high-pressure fluid to enter the cooling tank for cooling. The cooled fluid is then discharged into the mud pool for waste liquid treatment.

Images