阅读说明：本技术 一种油气井工作液高温高压沉降稳定性测试装置及方法 (Device and method for testing high-temperature high-pressure sedimentation stability of working fluid of oil-gas well ) 是由 肖刚 徐兴华 宋芳 李�荣 刘锐可 于 2020-05-08 设计创作，主要内容包括：本发明公开了一种油气井工作液高温高压沉降稳定性测试装置及方法,属于石油天然气用液体测试技术领域。所述测试装置包括静恒温单元、耐高温高压老化罐和沉降稳定性测试单元,该装置结构简单、拆装方便且可重复使用,能准确的模拟实际钻井现场高温高压的工程条件,并完成高密度油气井工作液在高温高压环境条件下静置后的沉降稳定性测试。本发明还提供了一种采用上述装置的测试方法,通过该装置可实现针对不同密度油气井工作液经过不同温度、不同压力、不同静置时间后,工作液沉降稳定性的测量和评价,为现场作业选择高密度油气井工作液类型和工作液的性能参数提供更准确的参考。(The invention discloses a device and a method for testing high-temperature high-pressure sedimentation stability of working fluid of an oil-gas well, and belongs to the technical field of testing of liquid for petroleum and natural gas. The testing device comprises a static constant temperature unit, a high-temperature and high-pressure resistant aging tank and a sedimentation stability testing unit, is simple in structure, convenient to disassemble and assemble, reusable, and capable of accurately simulating high-temperature and high-pressure engineering conditions of an actual drilling site and completing sedimentation stability testing after the high-density oil-gas well working fluid is kept still under the high-temperature and high-pressure environment conditions. The invention also provides a testing method adopting the device, and the device can realize the measurement and evaluation of the sedimentation stability of the working fluid after the working fluid of different densities passes through different temperatures, different pressures and different standing times, thereby providing more accurate reference for selecting the type of the working fluid of the high-density oil-gas well and the performance parameters of the working fluid for field operation.)

1. The utility model provides an oil gas well working fluid high temperature high pressure subsides stability testing arrangement which characterized in that includes:

the high-temperature and high-pressure aging resistant tank is provided with a tank body and a piston cover;

the static constant temperature unit is provided with a control box, and a maintenance kettle, a pressurizing container and a pressurizing pump which are sequentially connected through pipelines; the maintenance kettle is provided with a heating assembly, a temperature sensor and a pressure sensor, and can accommodate the high-temperature and high-pressure resistant aging tank;

the sedimentation stability testing unit is provided with a support, a bracket, an electric cabinet, a pressure sensor and a testing system; the support is arranged above the support, an electric sliding rail is arranged above the support, and a test platform is arranged below the support and used for placing a high-temperature and high-pressure resistant aging tank; the pressure sensor is arranged on the electric slide rail; a probe moving longitudinally is arranged on a probe of the pressure sensor; the electric control box is electrically connected with the electric slide rail; and the test system is electrically connected with the pressure sensor and the electric cabinet.

2. The device for testing the high-temperature high-pressure sedimentation stability of the oil and gas well working fluid as claimed in claim 1, wherein the maintenance kettle comprises a top cover and a kettle body, the pipeline penetrates through the top cover and extends into the maintenance kettle, and a sealing ring is further arranged at the bottom of the pipeline penetrating through the top cover.

3. The oil and gas well working fluid high-temperature high-pressure sedimentation stability testing device as claimed in claim 2, wherein a groove is formed in the top of the upper opening of the kettle body, and a connecting plate with a screw hole is formed in the outer side wall of the kettle body; the top cap bottom be equipped with the sealed sand grip of recess matching, the top cap lateral wall be equipped with the hangers of the area screw that the connecting plate matches, fixed connection can be realized through the bolt to connecting plate and hangers.

4. The oil and gas well working fluid high-temperature high-pressure sedimentation stability test device according to claim 1, wherein the diameter of the piston cover is adapted to the diameter of the inner cavity of the tank body, and the piston cover is arranged in the inner cavity of the tank body and forms piston connection with the inner wall of the tank body; a sealing ring is arranged on the side wall of the piston cover, which is contacted with the inner wall of the tank body; the center of the piston cover is provided with a vertically penetrating screw hole, and the top of the piston cover is also provided with a screw hole sealing element.

5. The oil and gas well working fluid high-temperature high-pressure sedimentation stability testing device as claimed in claim 4, wherein the screw hole sealing member comprises a screw rod, a sealing plate and an anti-skid rotary rod which are fixedly connected in sequence from bottom to top, and the screw rod is fixedly connected with the screw hole in a detachable thread manner; the diameter of the sealing platform is larger than that of the screw rod, and a sealing ring is arranged at the bottom of the sealing platform.

6. The oil and gas well working fluid high-temperature high-pressure sedimentation stability testing device as claimed in claim 5, wherein the inner wall of the tank body is provided with a limiting table, and the limiting table is arranged at the highest liquid level inside the tank body.

7. A method for testing the high-temperature high-pressure sedimentation stability of an oil-gas well working fluid is characterized by being implemented by adopting the device for testing the high-temperature high-pressure sedimentation stability of the oil-gas well working fluid, which comprises the following steps of:

s1, aging and rolling the pretested oil-gas well working fluid in a temperature environment simulating the underground operation temperature, pouring the aged fluid into a high-temperature-resistant high-pressure-resistant aging tank, and sealing;

s2, placing the high-temperature and high-pressure resistant aging tank subjected to the step S1 in a curing kettle, and then starting a static constant temperature unit to heat and pressurize the high-temperature and high-pressure resistant aging tank to a target temperature and a target pressure; then preserving heat and pressure for a required standing time to enable the working fluid of the oil-gas well to naturally settle, cooling and relieving pressure after the experiment is finished, and taking out the high-temperature and high-pressure resistant aging tank;

s3, placing the high-temperature and high-pressure resistant aging tank subjected to the step S2 on a test platform, starting a sedimentation stability test unit, enabling the probe to be placed into the high-temperature and high-pressure resistant aging tank downwards at a constant speed, and continuously transmitting data of the pressure sensor to a test system in the downward moving process of the probe;

and S4, the test system processes and analyzes the data to obtain the sedimentation stability of the oil-gas well working fluid after long-time high-temperature high-pressure rest.

8. The method for testing the high-temperature high-pressure sedimentation stability of the oil and gas well working fluid according to claim 7, wherein in the step S2, the maintenance kettle is pressurized by adopting air pressure or oil pressure.

9. The method for testing the high-temperature high-pressure sedimentation stability of the oil and gas well working fluid according to claim 7, wherein in the step S2, the required temperature is in accordance with the temperature range required by site construction, and the required standing time is in accordance with the standing time range required by site construction.

10. The method for testing the high-temperature high-pressure sedimentation stability of the oil and gas well working fluid according to claim 7, wherein in the step S3, three different measuring points are selected for the oil and gas well working fluid at the same horizontal height, and the three measuring points are located on the quartering point of the horizontal diameter of the high-temperature high-pressure aging resistant tank.

Technical Field

The invention relates to the technical field of testing of liquids for petroleum and natural gas, in particular to a high-temperature high-pressure sedimentation stability testing device for an oil-gas well working fluid and a method for testing sedimentation stability of a high-density oil-gas well working fluid by using the device.

Background

In recent years, with the continuous and deep research and development in the field of petroleum and natural gas in China, drilling operation is gradually developed from shallow strata, simple strata to deep strata and complex strata, wherein deep wells and ultra-deep wells are the key points for future exploration and development. In the drilling process, the drilling stratum is more and more complex, and the drilling construction difficulty is more and more large. Among them, oil-based drilling fluids have been developed as important means for drilling highly difficult deep wells, shale gas wells, large-inclination directional wells, horizontal wells, and various complex formation wells due to excellent properties such as inhibition, lubricity, thermal stability, contamination resistance, reservoir protection, and the like. The well slurry is often used on site for performance improvement and then is directly used as a high-density oil and gas well working fluid. The oil and gas well working fluid obtained by improving the oil-based drilling fluid also faces the common problems of the oil-based drilling fluid. For example, the ultra-high density (more than or equal to 2.4 g/cm) has been used for a long time³) The oil-based drilling fluid has extremely high solid content, the rheological property and the suspension capacity of the oil-based drilling fluid are difficult to coordinate, or the viscosity is too high, the flow resistance is too large, and the drilling discharge capacity cannot meet the requirement of cleaning a well hole; or the viscosity is insufficient, and the weighting agent in the drilling fluid is seriously settled at high temperature, low flow rate or static state in the well to cause faults, so the weighting agent is extremely difficult to prepare and has poor stability, and is difficult to adapt to the requirements of long-time drilling and oil testing of ultra-deep oil and gas wells and high-pressure shale gas wells. Meanwhile, the water-in-oil type emulsifier commonly used at home and abroad at present mainly comprises higher fatty acid soap, Span80, oleic acid, naphthenic acid amide, calcium naphthenate, iron petroleum sulfonate, amine derivatives of fatty acid and the like, mainly takes a single-chain surfactant as a main component, and has relatively low price, but large addition amount, poor emulsifying effect and insufficient high temperature resistance. When the temperature reaches 180 DEG CIn time, the problems of demulsification, viscosity reduction, rapid increase of filtration loss and the like are easy to occur.

In the construction process of the high-density oil-gas well working fluid on the oil testing site, the high-density solid-phase precipitation phenomenon is easy to generate under the long-term (12-20 days) high-temperature and high-pressure static state, so that the oil testing pipe column above the packer is buried or clamped, and the operation risk is caused. Therefore, the sedimentation stability of the working solution when the working solution is used in a high-temperature and high-pressure environment is judged so as to select a proper working solution for construction, and the method is very important for the field of oil testing exploration.

In order to evaluate the sedimentation stability of the working solution, the existing device generally adopts a glass rod probing method to qualitatively test precipitates and cured substances deposited at the bottom of a tank after high-temperature static aging so as to evaluate the sedimentation degree of the precipitates and qualitatively evaluate the sedimentation stability of the working solution according to the sedimentation degree. Although the device is simple, the device is only qualitative evaluation and cannot completely simulate the bottom hole condition, the bottom hole has two conditions of high temperature and high pressure, and the common method only simulates the high temperature environment but neglects the high pressure environment. Utility model patent 'determination system that stability was subsided to working solution's utility model patent with publication number CN206557042U discloses a system is confirmed to working solution settlement stability, and this system has solved the technical problem that current device can not be more accurate carry out quantitative evaluation to the stability that subsides of high density oil gas well working solution under the high temperature condition, still can not simulate the environment that has high temperature and high pressure in the pit shaft simultaneously completely still. Through multiple experiments of the inventor, the measured settleability data of the high-density oil-gas well working fluid in the simulated high-temperature environment is greatly different from the settleability data measured in the simulated underground real high-temperature high-pressure environment, so that the settleability of the high-density oil-gas well working fluid is measured only by simulating the high-temperature environment, and accurate reference cannot be provided for the selection of the type of the high-density oil-gas well working fluid and the performance parameters of the working fluid for field operation.

Disclosure of Invention

The invention aims to provide a device and a method for testing the high-temperature high-pressure sedimentation stability of oil-gas well working fluid, the testing device is simple in structure, convenient to disassemble and assemble and capable of being repeatedly used through reasonable design, the actual high-temperature high-pressure engineering conditions can be more accurately simulated by matching with a control system, and the device can be used for measuring and evaluating the sedimentation stability of the working fluid after the oil-gas well working fluid with different densities passes through different temperatures, different pressures and different standing times, so that more accurate reference is provided for selecting the type of the high-density oil-gas well working fluid and the performance parameters of the working fluid for field operation.

The technical purpose of the invention is realized by the following technical scheme:

the utility model provides an oil gas well working fluid high temperature high pressure subsides stability testing arrangement, includes:

the high-temperature and high-pressure resistant aging tank is provided with a tank body and a piston cover and is used for containing oil-gas well working fluid;

the static constant temperature unit is used for carrying out underground high-temperature and high-pressure simulation on the high-temperature and high-pressure resistant aging tank filled with the oil-gas well working fluid; the device comprises a control box, a curing kettle, a pressurizing container and a booster pump, wherein the control box is electrically connected with the curing kettle, and the curing kettle, the pressurizing container and the booster pump are sequentially connected through pipelines; a pipeline switch is arranged between the pressurizing container and the pressurizing pump; the maintenance kettle comprises a top cover and a kettle body, wherein a heating assembly, a temperature sensor and a pressure sensor are arranged in the kettle body, a liquid discharge valve is arranged at the bottom of the kettle body, an overpressure safety valve is arranged on the top cover, and the pipeline penetrates through the top cover and extends into the maintenance kettle; the maintenance kettle can contain the high-temperature and high-pressure resistant aging tank;

the sedimentation stability testing unit is used for testing the sedimentation stability of the oil-gas well working fluid subjected to high-temperature and high-pressure simulation by the static constant-temperature unit; the device comprises a support, a bracket, an electric cabinet, a pressure sensor and a test system; the support is arranged above the support, an electric sliding rail is arranged above the support, and a test platform is arranged below the support and used for placing a high-temperature and high-pressure resistant aging tank; the pressure sensor is arranged on the electric slide rail; a probe is arranged on a probe of the pressure sensor, and the probe can move longitudinally so as to stretch into or pull out of the high-temperature and high-pressure resistant aging tank; the electric control box is electrically connected with the electric slide rail; and the test system is electrically connected with the pressure sensor and the electric cabinet.

Furthermore, quiet constant temperature unit still includes the base, booster pump, pressurized container and maintenance cauldron are all installed on the base.

Further, the static thermostatic unit further comprises a collecting container, and the collecting container is arranged below the liquid discharge valve.

Furthermore, a pressure adjusting handle is also arranged on the booster pump.

Furthermore, a pressure gauge is further arranged on the top cover.

Furthermore, a sealing ring is arranged at the bottom of the top cover of the maintenance kettle through which the pipeline penetrates.

Furthermore, a groove is formed in the top of an upper opening of the kettle body, and a connecting plate with a screw hole is arranged on the outer side wall of the kettle body; the bottom of the top cover is provided with a sealing convex strip matched with the groove, the outer side wall of the top cover is provided with a hanging lug matched with the connecting plate and provided with a screw hole, and the connecting plate and the hanging lug can be fixedly connected through a bolt.

Further, the heating component is a heating wire.

Furthermore, the diameter of the piston cover is adapted to that of the inner cavity of the tank body, and the piston cover is arranged in the inner cavity of the tank body and is in piston connection with the inner wall of the tank body; a sealing ring is arranged on the side wall of the piston cover, which is contacted with the inner wall of the tank body; a vertically penetrating screw hole is formed in the center of the piston cover, and a screw hole sealing piece is further arranged at the top of the piston cover; the screw hole sealing piece comprises a screw rod, a sealing plate and an anti-skid rotary rod which are fixedly connected in sequence from bottom to top, and the screw rod is fixedly connected with the screw hole in a detachable thread manner; the diameter of the sealing platform is larger than that of the screw rod, and a sealing ring is arranged at the bottom of the sealing platform.

Further, the internal wall of jar is equipped with spacing platform, the highest liquid level department of the internal portion of jar is located to spacing platform.

Furthermore, an operation screen and an emergency stop switch are also arranged on the electric cabinet.

Further, the probe is a cylindrical probe, and the head of the cylindrical probe is hemispherical.

Further, the measuring range of the pressure sensor is 0-50N.

Furthermore, the high-temperature and high-pressure resistant aging tank is made of Hastelloy B, the outer diameter of the bottom surface of the high-temperature and high-pressure resistant aging tank is 8cm, the height of the high-temperature and high-pressure resistant aging tank is 25cm, and the inner diameter of the high-temperature and high-pressure resistant aging tank is 6.5 cm.

The method for testing the sedimentation stability of the high-density oil-gas well working fluid by adopting the device for testing the high-temperature high-pressure sedimentation stability of the oil-gas well working fluid comprises the following steps:

s1, aging and rolling the pretested oil-gas well working fluid in a temperature environment simulating the underground operation temperature, pouring the aged fluid into a high-temperature-resistant high-pressure-resistant aging tank, and sealing;

s2, placing the high-temperature and high-pressure resistant aging tank subjected to the step S1 in a curing kettle, and then starting a static constant temperature unit to heat and pressurize the high-temperature and high-pressure resistant aging tank to a target temperature and a target pressure; then preserving heat and pressure for a required standing time to enable the working fluid of the oil-gas well to naturally settle, cooling and relieving pressure after the experiment is finished, and taking out the high-temperature and high-pressure resistant aging tank;

s3, placing the high-temperature and high-pressure resistant aging tank subjected to the step S2 on a test platform, starting a sedimentation stability test unit, enabling the probe to be placed into the high-temperature and high-pressure resistant aging tank downwards at a constant speed, and continuously transmitting data of the pressure sensor to a test system in the downward moving process of the probe;

and S4, the test system processes and analyzes the data to obtain the sedimentation stability of the oil-gas well working fluid after long-time high-temperature high-pressure rest.

More specifically, the method for testing the sedimentation stability of the working fluid in the high-density oil-gas well comprises the following detailed steps:

s1, aging and rolling the pretested high-density oil and gas well working fluid for 16 hours in a temperature environment simulating the downhole operation temperature, and cooling to determine the density and rheological property of the high-density oil and gas well working fluid; assembling a high-density oil-gas well working fluid static constant temperature unit and ensuring that a liquid discharge valve is in a closed state; then slowly pouring the aged high-density oil-gas well working fluid into a high-temperature and high-pressure resistant aging tank body, stirring with a glass rod to expel bubbles, taking out a screw hole sealing piece on a piston cover from a screw hole, pressing the piston cover into the tank body, and sealing the screw hole with the screw hole sealing piece;

s2, vertically placing the high-temperature and high-pressure aging resistant tank which is installed in the step S1 in a maintenance kettle body, and installing a top cover to seal the maintenance kettle; then, a booster pump, a pipeline switch and a pressurizing container are opened, and the maintenance kettle is pressurized; pressurizing to 0.5-1 MPa, starting a heating assembly in the curing kettle to heat the aging tank, and slowly pressurizing to the required pressure if the pressure does not reach the required pressure after the temperature is raised to the required temperature; in the process, the pressure and the temperature in the curing kettle are monitored, adjusted and controlled through the control box; then preserving heat and pressure for a required standing time to enable the high-density oil-gas well working fluid to naturally settle, cooling and relieving pressure after the experiment is finished, opening the top cover of the curing kettle, taking out the high-temperature and high-pressure resistant aging tank, rotating an anti-skidding rotary rod on a piston cover to screw out a screw rod from a screw hole, releasing the pressure in the tank body through the screw hole, and taking out the piston cover from the tank body;

s3, placing the high-temperature and high-pressure resistant aging tank body subjected to the step S2 on a test platform, starting a test system and an electric cabinet of the sedimentation stability test unit, controlling an electric slide rail by the electric cabinet to drive a pressure sensor probe to be downwards placed into the high-temperature and high-pressure resistant aging tank at a constant speed, and continuously transmitting data of the pressure sensor to the test system in the downward moving process of the probe;

and S4, processing the data by the test system, displaying a sedimentation resistance change curve in real time by taking the horizontal axis as displacement and the vertical axis as pressure, and testing the sedimentation degree of the high-density oil-gas well working fluid after long-time high-temperature high-pressure rest.

Further, in step S2, the curing kettle may be pressurized by air pressure or oil pressure.

Further, the method for oil pressure pressurization comprises the following steps: fully preparing base oil of high-density oil-gas well working fluid as hydraulic oil in a pressurizing container, opening a booster pump, a pipeline switch and the pressurizing container, and adding the base oil into a maintenance kettle; when the pressure of the maintenance kettle is relieved, the liquid discharging valve needs to be opened, and the base oil in the maintenance kettle is placed into the collecting container.

Further, in the step S2, the required temperature is in accordance with a temperature range required by the site construction, and the required standing time is in accordance with a standing time range required by the site construction.

Further, in the step S3, the probe moves at a speed of 20 to 40 mm/sec.

As a preferable scheme, when the sedimentation stability of the high-density oil-gas well working fluid is tested, three different measuring points are selected for the high-density oil-gas well working fluid at the same horizontal height to carry out measurement, and the three measuring points are positioned on the quartering point of the horizontal diameter of the high-temperature and high-pressure resistant aging tank.

Compared with the prior art, the testing device for the high-temperature high-pressure sedimentation stability of the working fluid of the oil-gas well is simple and reasonable in structural design, convenient to disassemble, assemble and maintain and capable of being repeatedly used, and is convenient for the high-efficiency development of testing work; in performance, the device can realize the simulation of the high-temperature and high-pressure environment when the working fluid works underground, so that the test environment is closer to the actual working condition in the shaft bottom, the heat preservation and pressure maintaining time of the device is long, and the sedimentation condition of the high-density oil-gas well working fluid after the shaft bottom is still can be simulated for a long time. Meanwhile, the device can realize qualitative measurement and evaluation of the sedimentation stability of the high-density oil-gas well working fluid subjected to different temperatures, different pressures, different densities and different standing times, and the method for testing the high-temperature high-pressure sedimentation stability of the oil-gas well working fluid, provided by the invention, has the advantages of convenience and safety in operation, simplicity in data interpretation and accurate test result, and provides more accurate reference for selecting the type of the high-density oil-gas well working fluid and the performance parameters of the working fluid for field operation.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural view of a static thermostatic unit according to the present invention.

FIG. 2 is a schematic view of the structure of the curing kettle of the present invention.

FIG. 3 is a schematic view of a partial cross-section of a curing pot according to the present invention.

FIG. 4 is a schematic structural diagram of the high temperature and high pressure resistant aging tank of the present invention.

Fig. 5 is a partial cross-sectional view of the piston cap of fig. 4 pressed into a can body.

Fig. 6 is a schematic structural diagram of the high-temperature and high-pressure resistant aging tank with the piston cover inverted.

Fig. 7 is a schematic structural diagram of a sedimentation stability test unit according to the present invention.

FIG. 8 is a diagram illustrating a selection method of measurement points according to the present invention.

FIG. 9 is a graph showing the change of the sedimentation resistance of the working fluid in the high-density oil-gas well in example 2 of the present invention at a constant temperature for 15 days.

In the figure:

1-static constant temperature unit, 11-control box,

12-curing kettle, 121-top cover, 122-kettle body, 123-electric heating wire, 124-temperature sensor, 125-pressure sensor, 126-liquid discharge valve, 127-overpressure safety valve, 128-pressure gauge, 129-sealing ring,

13-a pressurized container, 14-a booster pump, 141-an adjusting handle, 15-a pipeline, 16-a pipeline switch, 17-a base and 18-a collecting container;

2-high temperature and high pressure resistant aging tank, 21-tank body, 211-limit table, 22-piston cover, 221-sealing ring, 222-screw hole, 223-screw hole sealing element, 223 a-screw rod, 223 b-sealing table and 223 c-rotary rod;

3-a sedimentation stability testing unit, 31-a support, 32-a support, 33-an electric cabinet, 331-an operation screen, 332-an emergency stop switch, 34-a pressure sensor, 341-a probe, 342-a probe, 35-a testing system, 36-an electric slide rail and 37-a testing platform.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the above description of the present invention, it is to be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer", and the like are used in the orientations and positional relationships indicated in the drawings, or the orientations and positional relationships conventionally used in the products of the present invention, or the orientations and positional relationships conventionally understood by those skilled in the art, are used for convenience of description and simplification of the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention.