CN113605885A - Simulation device and simulation method for micro-huff and puff of drilling fluid in fractured stratum - Google Patents

Simulation device and simulation method for micro-huff and puff of drilling fluid in fractured stratum Download PDF

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Publication number
CN113605885A
CN113605885A CN202110963687.9A CN202110963687A CN113605885A CN 113605885 A CN113605885 A CN 113605885A CN 202110963687 A CN202110963687 A CN 202110963687A CN 113605885 A CN113605885 A CN 113605885A
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China
Prior art keywords
pressure
pipeline
control system
liquid
drilling fluid
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CN202110963687.9A
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Chinese (zh)
Inventor
刘书杰
刘和兴
马传华
柳亚亚
吴艳辉
黄静
蔡饶
陈鹏
劳扬帆
宋浩林
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CNOOC China Ltd Zhanjiang Branch
CNOOC China Ltd Hainan Branch
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CNOOC China Ltd Zhanjiang Branch
CNOOC China Ltd Hainan Branch
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Priority to CN202110963687.9A priority Critical patent/CN113605885A/en
Publication of CN113605885A publication Critical patent/CN113605885A/en
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    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B49/00Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B47/00Survey of boreholes or wells
    • E21B47/10Locating fluid leaks, intrusions or movements

Abstract

The invention discloses a simulation device for micro huff and puff of drilling fluid in a fractured stratum, which comprises a rock core with a crack, a main body system for clamping the rock core and pressurizing the rock core, wherein the main body system is provided with an axial pressure loading cavity and a confining pressure loading cavity, the simulation device also comprises a liquid injection system for injecting simulated shaft fluid into the crack, an axial pressure liquid injection control system for simulating the confining pressure of the rock core stratum, a confining pressure liquid injection control system for simulating the opening pressure of the fractured stratum, a back pressure control system for controlling the pressure in a back spit stage and a high-pressure visual metering system for quantitatively analyzing the back spit stage of respiratory effect fluid, the liquid injection system is communicated with the crack, the axial pressure control system is communicated with the axial pressure loading cavity, the confining pressure liquid injection control system is communicated with the confining pressure loading cavity, the back pressure control system is connected on a pipeline between the liquid injection system and the crack, the high-pressure visual metering system is communicated with the back pressure control system. The invention can realize the quantitative description and dynamic characterization of the respiratory effect.

Description

Simulation device and simulation method for micro-huff and puff of drilling fluid in fractured stratum
Technical Field
The invention relates to the technical field of drilling fluid drilling, in particular to a device and a method for simulating micro huff and puff of drilling fluid in a fractured stratum.
Background
Currently, when drilling operations are performed at a narrow window, the Equivalent Circulating Density (ECD) of the drilling fluid easily exceeds the fracture pressure of the formation, at this time, the drilling fluid is lost, and after the pump is stopped, the ECD is reduced, and the fluid lost to the formation is re-circulated into the wellbore, which is called a breathing effect. Misjudgment of formation breathing effects and kicks can cause a series of problems: if the breathing effect is misjudged as a kick, the usual treatment is to increase the drilling fluid density, which means that the bottom hole pressure will exceed the formation fracture pressure further and cause more severe loss.
In the prior art, the experimental study aiming at the stratum respiration effect mainly studies the characteristics of a rock core, such as cracks, and the like in a coring mode, the quantitative description of the drilling fluid leakage amount in the respiration effect generation process and the dynamic characterization of the crack opening and closing are lacked, and the reference significance of the experimental result on the working condition of the respiration effect generated when the actual drilling meets the natural crack stratum is limited. Therefore, there is a need to provide a new device and method that can simulate the respiration effect of the natural fracture formation and can realize the quantitative description and dynamic characterization of the respiration effect.
The Chinese patent application, publication No. CN107869345A, discloses a test device and a test method for simulating the shaft breathing effect, and the technical scheme also has the defects of lack of quantitative description of drilling fluid leakage in the breathing effect generation process and dynamic characterization of crack opening and closing.
Disclosure of Invention
The invention provides a simulation device for simulating the micro-throughput of drilling fluid in a fractured stratum, aiming at solving the problems that the prior art lacks quantitative description of drilling fluid leakage in the respiratory effect generation process and dynamic characterization of fracture opening and closing and cannot accurately simulate the respiratory effect of a natural fractured stratum.
In order to solve the technical problems, the invention adopts the technical scheme that: a simulation device for trace huff and puff of drilling fluid in a fractured stratum comprises a rock core with a crack, a main body system for clamping the rock core and pressurizing the rock core, an injection system for injecting simulated wellbore fluid into the crack of the rock core, an axial pressure injection control system for simulating the confining pressure of the rock core stratum, a confining pressure injection control system for simulating the opening pressure of the fractured stratum, a back pressure control system for controlling the pressure in a back spitting stage and a high-pressure visual metering system for quantitatively analyzing the back spitting stage of respiratory effect fluid, wherein the injection system is communicated with the crack through a pipeline, and the axial pressure injection control system is communicated with the axial pressure loading cavity through a pipeline, the confining pressure liquid injection control system is communicated with the confining pressure loading cavity through a pipeline, the back pressure control system is connected to the pipeline between the liquid injection system and the crack, and the high-pressure visual metering system is communicated with the back pressure control system.
In the technical scheme, the formation confining pressure is simulated through the axial pressure liquid injection control system, the opening pressure of a crack in a rock core is simulated through the confining pressure liquid injection control system, and the real formation pressure environment is simulated through the axial pressure liquid injection control system and the confining pressure liquid injection control system. The respiratory effect can be quantitatively analyzed through the high-pressure visual metering device, and the dynamic opening and closing characteristics of the formation fracture in the actual working condition can be simulated through the confining pressure effect and the rock core; the high-pressure visual device can simulate the actual working condition of high pressure of a shaft in the respiratory effect regurgitation process; the simulation result is closer to the actual stratum condition and the drilling working condition, the cognition on the respiration effect is enhanced, the technical support is further provided for drilling the deep complex stratum or the natural fracture stratum under the deep water and other environments, the drilling efficiency is improved, the drilling cost is saved, and the drilling risk is reduced.
Preferably, the main part system includes outer sleeve, rigid seal cover, axle pressure bearing end and axle pressure loading end, the rock core is installed in the outer sleeve, the rigid seal cover cladding is in the rock core periphery and be located in the outer sleeve, be provided with the through hole on the axle pressure bearing end, the through hole with crack in the rock core is linked together, axle pressure bearing end and axle pressure loading end are located in the outer sleeve and be located respectively the both sides of rigid seal cover, install the gum cover on axle pressure bearing end, rigid seal cover and the axle pressure loading end, the gum cover with constitute between the outer sleeve confined pressure loading cavity, axle pressure loading end with constitute between the outer sleeve axle pressure loading cavity.
Preferably, the axial compression loading end comprises a first connecting piece and a sliding sleeve which are connected with the rigid sealing sleeve, the sliding sleeve is in sliding connection with the outer sleeve, the first connecting piece is connected with the sliding sleeve, a convex ring is arranged on the sliding sleeve, a boss is arranged on the outer sleeve, and the convex ring, the sliding sleeve and the boss form an axial compression loading cavity.
Preferably, the liquid injection system comprises a first liquid storage tank, a first liquid pump, a first pipeline and a first pressure sensor for monitoring the liquid pressure in the first pipeline, one end of the first pipeline is connected with the first liquid storage tank, and the other end of the first pipeline is connected with the through hole; the first liquid pump and the first pressure sensor are mounted on the first pipe.
Preferably, the axial compression liquid injection control system comprises a second liquid storage tank, a second liquid pump, a second pipeline and a second pressure sensor for monitoring the liquid pressure in the second pipeline, wherein one end of the second pipeline is connected with the second liquid storage tank, and the other end of the second pipeline is connected with the axial compression loading cavity; the second hydraulic pump and the second pressure sensor are mounted on the second pipeline.
Preferably, the confining pressure liquid injection control system comprises a third liquid storage tank, a third liquid pump, a third pipeline and a third pressure sensor for monitoring the liquid pressure in the third pipeline, wherein one end of the third pipeline is connected with the third liquid storage tank, and the other end of the third pipeline is connected with the confining pressure loading cavity; the third liquid pump and the third pressure sensor are mounted on a third pipe.
Preferably, the back pressure control system includes back pressure pump, back pressure valve, first valve and fourth pipeline, back pressure pump, back pressure valve and first valve are linked together through the fourth pipeline, first valve is close to the rock core side, the one end of fourth pipeline with annotate the liquid system and be linked together, the first port of back pressure valve with first valve links to each other, the second port of back pressure valve with the back pressure pump links to each other, the third port of back pressure valve with the visual measurement system of high pressure is linked together.
Preferably, the high-pressure visual metering system comprises a high-pressure visual metering device and a camera device for shooting data on the high-pressure visual metering device, and the high-pressure visual metering device is communicated with the third port of the back pressure valve.
The invention also provides a method for simulating the micro throughput of the drilling fluid in the fractured stratum, which comprises the following steps:
s1: matching the initial pressure of the back pressure control system with the pressure of a shaft near the simulated natural fracture formation based on the parameters of the simulated natural fracture formation;
s2: starting the axial pressure injection control system and the confining pressure injection control system to inject pressure to the main body system, so that the confining pressure is matched with the opening pressure of the natural fracture stratum, and the axial pressure is matched with the confining pressure of the natural fracture stratum;
s3: starting an injection system, setting the pressure as the simulated wellbore pressure, injecting liquid into the cracks of the rock core, increasing the injection pressure of the injection system after the flow of the injection system is not changed, enabling the flow passage pressure to exceed the simulated natural crack stratum starting pressure, and measuring the flow change by using a metering system of a pump in the injection system;
s4: and closing the liquid injection system, opening a passage of the back pressure control system, and measuring the flow change by using the high-pressure visual measuring system.
Preferably, steps S1 to S5 are repeated to increase the initial pressure of the back pressure control system or change the axial pressure of the axial pressure priming control system or change the fluid pressure of the priming system.
Compared with the prior art, the invention has the beneficial effects that: the device performs experimental study and quantitative analysis on the respiratory effect of the fractured stratum under the conditions of reducing the real stratum condition and the actual working condition, provides technical reference for drilling the natural fractured stratum under the conditions of deep complex stratum, deep water and the like, strengthens the cognition on the respiratory effect, reduces the occurrence of underground complex conditions such as kick and the like caused by misjudgment on the respiratory effect, saves the drilling cost, improves the drilling efficiency and reduces the drilling risk.
Drawings
FIG. 1 is a schematic diagram of the structure of the simulation apparatus of the present invention;
FIG. 2 is a schematic diagram of the structure of the main body system in the simulation apparatus according to the present invention;
FIG. 3 is a schematic diagram of the high-pressure visual metering system in the simulation apparatus according to the present invention;
FIG. 4 is a flow chart of a simulation method of the present invention;
FIG. 5 is a schematic diagram of fracture dynamics during the occurrence of natural fracture formation breathing effects.
In the drawings: 1. a core; 2. a body system; 3. a shaft pressure loading cavity; 4. a confining pressure loading cavity; 5. a liquid injection system; 6. a shaft-pressing liquid injection control system; 7. a confining pressure liquid injection control system; 8. a back pressure control system; 9. a high pressure visual metering system; 11. cracking; 21. an outer sleeve; 22. a rigid seal cartridge; 23. a bearing end is axially pressed; 24. a shaft pressure loading end; 25. a rubber sleeve; 241. a first connecting member; 242. a sliding sleeve; 243. a convex ring; 244. a boss; 51. a first liquid storage tank; 52. a first liquid pump; 53. a first conduit; 54. a first pressure sensor; 55. a first solenoid valve; 61. a second liquid storage tank; 62. a second liquid pump; 63. a second conduit; 64. a second pressure sensor; 65. a second solenoid valve; 71. a third liquid storage tank; 72. a third liquid pump; 73. a third pipeline; 74. a third pressure sensor; 75. a third electromagnetic valve; 81. a back pressure pump; 82. a back pressure valve; 83. a first valve; 84. a fourth conduit; 85. a second valve; 86. a pressure gauge; 91. a high pressure visual metering device; 92. a camera device; 93. a flow meter; 94. a light source.
Detailed Description
The drawings are for illustrative purposes only and are not to be construed as limiting the patent; for the purpose of better illustrating the embodiments, certain features of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted. The positional relationships depicted in the drawings are for illustrative purposes only and are not to be construed as limiting the present patent.
The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", "long", "short", etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the drawings, it is only for convenience of description and simplicity of description, but does not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore, the terms describing the positional relationships in the drawings are only used for illustrative purposes and are not to be construed as limitations of the present patent, and specific meanings of the terms may be understood by those skilled in the art according to specific situations.
The technical scheme of the invention is further described in detail by the following specific embodiments in combination with the attached drawings:
example 1
As shown in fig. 1 to 3, a simulation device for trace huff and puff of drilling fluid in a fractured formation comprises a core 1 provided with a crack 11, a main system 2 used for clamping the core 1 and pressurizing the core 1, an axial pressure loading cavity 3 used for axially pressurizing the core 1 and a confining pressure loading cavity 4 used for circumferentially pressurizing the core 1, an injection system 5 used for injecting simulated wellbore fluid into the crack 11 of the core 1, an axial pressure injection control system 6 used for simulating formation confining pressure of the core 1, a confining pressure injection control system 7 used for simulating formation opening pressure of the crack 11, a back pressure control system 8 used for controlling pressure in a back spitting stage, and a high-pressure visual metering system 9 used for carrying out quantitative analysis on a breathing effect fluid back spitting stage, wherein the injection system 5 is communicated with the crack 11 through a pipeline, the axial pressure injection control system 6 is communicated with the axial pressure loading cavity 3 through a pipeline, the confining pressure liquid injection control system 7 is communicated with the confining pressure loading cavity 4 through a pipeline, the back pressure control system 8 is connected to the pipeline between the liquid injection system 5 and the crack 11, and the high-pressure visual metering system 9 is communicated with the back pressure control system 8. In this embodiment, the formation confining pressure is simulated by the axial pressure injection control system 6, the opening pressure of the crack 11 in the core 1 is simulated by the confining pressure injection control system 7, and the real formation pressure environment is simulated by the arrangement of the axial pressure injection control system 6 and the confining pressure injection control system 7. The respiration effect can be quantitatively analyzed through a high-pressure visual metering device, and the characteristic of dynamic opening and closing of the formation fracture 11 in the actual working condition can be simulated through the confining pressure effect and the rock core 1; the high-pressure visual device can simulate the actual working condition of high pressure of a shaft in the respiratory effect regurgitation process; the simulation result is closer to the actual stratum condition and the drilling working condition, the cognition on the respiration effect is enhanced, the technical support is further provided for drilling the deep complex stratum or the natural fracture stratum under the deep water and other environments, the drilling efficiency is improved, the drilling cost is saved, and the drilling risk is reduced.
It should be noted that, in this embodiment, the fracture 11 on the core 1 adopts the artificial fracture 11, and the fracture 11 opening pressure can be set independently, so that the requirements on the experimental equipment are reduced, the experimental difficulty is reduced, and the experimental safety is enhanced. In addition, it should be noted that the artificial fracture 11 inside the core 1, the fracture 11 extends from one top end surface of the core 1 inwards along the axial direction of the core 1, but does not penetrate through the whole core 1; the crack 11 radially expands along the axial direction of the core 1 and does not penetrate through the side end face. The axial pressure liquid injection control system 6, the confining pressure liquid injection control system 7, the liquid injection system 5 and the back pressure control system 8 are all used for transmitting pressure through liquid.
The main body system 2 comprises an outer sleeve 21, a rigid sealing sleeve 22, a shaft pressure bearing end 23 and a shaft pressure loading end 24, the core 1 is installed in the outer sleeve 21, the rigid sealing sleeve 22 is coated on the periphery of the core 1 and located in the outer sleeve 21, a through hole is formed in the shaft pressure bearing end 23 and communicated with a crack 11 in the core 1, the shaft pressure bearing end 23 and the shaft pressure loading end 24 are arranged in the outer sleeve 21 and located on two sides of the rigid sealing sleeve 22 respectively, rubber sleeves 25 are installed on the shaft pressure bearing end 23, the rigid sealing sleeve 22 and the shaft pressure loading end 24, a confining pressure loading cavity 4 is formed between the rubber sleeves 25 and 21, and a shaft pressure loading cavity 3 is formed between the shaft pressure loading end 24 and the outer sleeve 21. In this embodiment, the bearing end 23 of the axial pressure, the rigid sealing sleeve 22 and the bearing end 23 of the axial pressure are jointly provided with a rubber sleeve 25, a confining pressure loading cavity 4 is formed between the rubber sleeve 25 and the outer sleeve 21, the confining pressure loading cavity 4 is communicated with the confining pressure injection control system 7 through a pipeline, and the confining pressure injection control system 7 can be used for simulating the cracking pressure 11 of the core 1 through the confining pressure loading cavity 4. And the axial pressure loading cavity 3 is formed between the axial pressure bearing end 23 and the outer sleeve 21, the axial pressure loading cavity 3 is communicated with the axial pressure injection control system 6 through a pipeline, and the axial pressure injection control system 6 can be used for simulating confining pressure of the stratum of the rock core 1 through the axial pressure loading cavity 3. It should be noted that the rigid sealing sleeve 22 can completely wrap the core 1, and only a prefabricated hole is left in the center of the end face contacting the crack 11, and the prefabricated hole connects the through hole on the axial compression bearing end 23 with the crack 11 on the core 1. Two top end surfaces of the rigid sealing sleeve 22 are respectively contacted with the axial pressure bearing end 23 and the axial pressure loading end 24, and the side surface of the rigid sealing sleeve 22 is provided with a rubber sleeve 25. In addition, it should be noted that the rigid sealing sleeve 22 may be a cement sealing sleeve or a steel sleeve. The size of the through hole is consistent with that of the prefabricated hole on the rigid sealing sleeve 22, and the size of the through hole is matched with that of a flow passage in the liquid injection system 5, so that the liquid injection flow passage is connected with the crack 11 through the through hole and the prefabricated hole. The pipeline of the axial compression liquid injection control system 6 connected with the axial compression loading cavity 3 is communicated with the axial compression loading cavity 3 through the mounting hole on the outer sleeve 21. And a pipeline of the confining pressure liquid injection control system 7 connected with the confining pressure loading cavity 4 is communicated with the confining pressure loading cavity 4 through another mounting hole on the outer sleeve 21.
In addition, the axial compression loading end 24 includes a first connecting member 241 connected to the rigid sealing sleeve 22 and a sliding sleeve 242, the first connecting member 241 is connected to the sliding sleeve 242, the sliding sleeve 242 is slidably connected to the outer sleeve 21, a protruding ring 243 is disposed on the sliding sleeve 242, a boss 244 is disposed on the outer sleeve 21, and the axial compression loading cavity 3 is formed among the protruding ring 243, the sliding sleeve 242 and the boss 244. In the present embodiment, since the annular axial compression loading cavity 3 is formed among the collar 243, the sliding sleeve 242 and the boss 244, the volume of the axial compression loading cavity 3 is smaller, and the required liquid is correspondingly reduced, so that the volume of the liquid pump in the axial compression liquid injection control system 6 can be reduced.
The liquid injection system 5 comprises a first liquid storage tank 51, a first liquid pump 52, a first pipeline 53 and a first pressure sensor 54 for monitoring the liquid pressure in the first pipeline 53, wherein one end of the first pipeline 53 is connected with the first liquid storage tank 51, and the other end of the first pipeline 53 is connected with a through hole; the first liquid pump 52 and the first pressure sensor 54 are mounted on the first pipe 53. In this embodiment, the injection system 5 is mainly used to provide a fluid pressure to inject a simulated wellbore fluid into the fracture 11 of the core 1. The first liquid pump 52 is a constant-pressure constant-speed pump, and can accurately control the output pressure of the simulated wellbore liquid through a corresponding controller, and can also obtain parameters such as flow in real time. The first liquid storage tank 51 is mainly used for providing simulated wellbore liquid, one end of the first liquid pump 52 is communicated with the first liquid storage tank 51, the other end of the first liquid pump 52 can be communicated with one end of a first electromagnetic valve 55, the other end of the first electromagnetic valve 55 is communicated with the crack 11 of the rock core 1, and all the components are communicated through a first pipeline 53. It should be noted that the first reservoir 51 may be a transparent structure, and the transparent structure is provided with scales, so that the volume of the liquid delivered to the fracture 11 of the core 1 can be known through the scales. Furthermore, a first pressure sensor 54 is used to monitor the pressure in the first conduit 53.
In addition, the axial compression liquid injection control system 6 comprises a second liquid storage tank 61, a second liquid pump 62, a second pipeline 63 and a second pressure sensor 64 for monitoring the liquid pressure in the second pipeline 63, one end of the second pipeline 63 is connected with the second liquid storage tank 61, and the other end is connected with the axial compression loading cavity 3; a second liquid pump 62 and a second pressure sensor 64 are mounted on the second pipe 63. In this embodiment, the second liquid storage tank 61 is used for providing the simulated axial pressure fluid, one end of the second liquid pump 62 is communicated with the second liquid storage tank 61, the other end of the second liquid pump 62 can be communicated with one end of a second electromagnetic valve 65, the other end of the second electromagnetic valve 65 is communicated with the axial pressure loading cavity 3, and all the components are communicated with each other through a second pipeline 63. The second pressure sensor 64 is used to monitor the pressure in the second conduit 63, i.e., the simulated axial pressure of the core 1. It should be noted that the second fluid pump 62 may be a manual pump.
The confining pressure liquid injection control system 7 comprises a third liquid storage tank 71, a third liquid pump 72, a third pipeline 73 and a third pressure sensor 74 for monitoring the liquid pressure in the third pipeline 73, wherein one end of the third pipeline 73 is connected with the third liquid storage tank 71, and the other end of the third pipeline 73 is connected with the confining pressure loading cavity 4; a third liquid pump 72 and a third pressure sensor 74 are mounted on the third pipe 73. In this embodiment, the third liquid storage tank 71 is used for providing a simulated confining pressure fluid, one end of the third liquid pump 72 is communicated with the third liquid storage tank 71, the other end of the third liquid pump 72 can be communicated with one end of a third electromagnetic valve 75, the other end of the third electromagnetic valve 75 is communicated with the confining pressure loading cavity 4, and all the components are communicated with each other through a third pipeline 73. The third pressure sensor 74 is used to monitor the pressure in the third conduit 73, i.e. to monitor the simulated confining pressure of the core 1. It should be noted that the third liquid pump 72 may be a manual pump.
In addition, the back pressure control system 8 includes a back pressure pump 81, a back pressure valve 82, a first valve 83 and a fourth pipeline 84, the back pressure pump 81, the back pressure valve 82 and the first valve 83 are communicated through the fourth pipeline 84, the first valve 83 is close to the rock core 1 side, one end of the fourth pipeline 84 is communicated with the liquid injection system 5, a first port of the back pressure valve 82 is connected with the first valve 83, a second port of the back pressure valve 82 is connected with the back pressure pump 81, and a third port of the back pressure valve 82 is communicated with the high-pressure visual metering system 9. In this embodiment, a pressure gauge is further disposed on the fourth pipe 84, and the magnitude of the pressure in the fourth pipe 84 can be visually checked through the setting of the pressure gauge. The back-pressure pump 81 may be a manual pump for supplying pressure to the back-pressure valve 82. The back pressure valve 82 is used primarily to simulate the wellbore pressure value during the breathing effect fluid regurgitation phase. A second valve 85 is provided between the back-pressure pump 81 and the back-pressure valve 82, and the first valve 83 is connected to a fourth pipe 84 connecting the back-pressure valve 82 and the first pipe 53. A pressure gauge 86 is also provided in the fourth pipe 84 between the second valve 85 and the back-pressure valve 82.
The high-pressure visual metering system 9 comprises a high-pressure visual metering device 91 and a camera device 92 for shooting data on the high-pressure visual metering device 91, and the high-pressure visual metering device 91 is communicated with the third port of the back pressure valve 82. The high-pressure visual metering device 91 comprises an autoclave and visual glass arranged on the side wall of the high-pressure autoclave, the flowmeter 93 can be seen through the visual glass, the camera 92 can shoot the flowmeter 93 through the visual glass, the total fluid amount can be observed, and the image can be further analyzed to obtain parameters such as the fluid return rate. It should be noted that, in order to obtain better shooting effect, the light source 94 may be further provided on the flowmeter 93 side, the distance d1 between the light source 94 and the flowmeter 93 should be as small as possible, and the distance d2 between the flowmeter 93 and the imaging device 92 may be adjusted.
Example 2
As shown in fig. 4, a simulation method of a simulation apparatus for drilling fluid in a fractured formation micro-stimulation includes the following steps:
s1: matching the initial pressure of the back pressure control system 8 with the pressure of the wellbore near the simulated natural fracture formation based on the simulated natural fracture formation parameters;
s2: starting the axial pressure injection control system 6 and the confining pressure injection control system 7 to inject pressure to the main body system 2, so that the confining pressure is matched with the opening pressure of the natural fracture stratum, and the axial pressure is matched with the confining pressure of the natural fracture stratum;
s3: starting the liquid injection system 5, setting the pressure as the simulated wellbore pressure, injecting liquid into the crack 11 of the core 1, increasing the liquid injection pressure of the liquid injection system 5 after the flow of the liquid injection system 5 is not changed, enabling the flow passage pressure to exceed the simulated natural crack formation starting pressure, and measuring the flow change by using a metering system of a pump in the liquid injection system 5;
s4: and (3) closing the liquid injection system 5, opening a passage of a back pressure control system 8, and metering the flow change by using a high-pressure visual metering system 9.
It should be noted that, in step 3, the hydraulic pressure of the injection system 5 is adjusted to exceed the opening pressure of the simulated natural fracture formation, the fracture 11 in the core 1 is expanded under the positive pressure difference between the hydraulic pressure of the flow channel and the confining pressure provided by the confining pressure injection control system 7, that is, the fracture width is increased, the simulated formation fluid in the corresponding flow channel leaks into the fracture 11, and in the simulation process, that is, under the positive pressure difference between the bottom hole pressure and the opening pressure of the natural fracture formation, the natural fracture is dynamically opened, that is, the drilling fluid leaks out in the respiratory effect. In the step 4, because the initial pressure of the back pressure control system 8 is matched with the initial simulated wellbore pressure, the pressure value is lower than the internal flowing pressure of the fracture 11 in the stage, under the action of the pressure difference, the fluid in the fracture 11 flows back to the passage of the back pressure control system 8 and enters the high-pressure visual metering device 91, the originally propped fracture 11 is closed again, the simulation process corresponds to the closing process of dynamic opening and closing of the natural fracture stratum in the respiratory effect generation process, and is the drilling fluid return stage in the respiratory effect generation process; the four steps are a complete respiratory effect simulation process. In particular, the dynamic changes of the slit 11 during the occurrence of the respiratory effect can be seen in conjunction with fig. 5.
In order to research the influence rule of different parameters on the respiratory effect, the parameters can be changed, the operation steps S1 to S5 are repeated, and a plurality of groups of experimental results are obtained to form contrast, wherein the comparison comprises the steps of further increasing the simulated wellbore pressure, increasing the pressure difference between the simulated wellbore pressure and the natural fracture opening pressure in the fracture 11 opening process, and researching the influence of the pressure difference on the respiratory effect; changing the axial pressure to research the influence rule of the formation confining pressure on the natural fracture formation respiration effect; the simulated wellbore fluid was modified to study the effect of drilling fluid rheology on respiratory effects, etc.
Example 3
A. Before the experiment is started, all parts are installed according to the connection relation shown in fig. 1, and the pipeline tightness is checked after the installation is finished, so that the pipeline tightness is ensured to be good, and all valves are in a closed state.
B. Debugging each component, and matching the initial pressure of the back pressure control system 8 with the simulated shaft pressure according to the shaft condition to be simulated after testing that each component has normal functions;
C. after the initial pressure is adjusted, injecting pressure into the main body system 2 through an axial pressure pump (namely, a second liquid pump 62) and a confining pressure pump (a third liquid pump 72) of the axial pressure injection control system 6, wherein the axial pressure is matched with the confining pressure of the simulated formation, and the confining pressure is matched with the opening pressure of the simulated natural fracture formation;
D. after the setting of the confining pressure and the axial pressure is finished, a constant-pressure constant-speed pump (namely a first liquid pump 52) in the liquid injection system 5 is started to inject liquid into the crack 11 of the core 1, the initial flow pressure is set to be the simulated wellbore pressure, the flow pressure of the constant-pressure constant-speed pump is increased after the flow rate is not obviously changed, the flow pressure exceeds the confining pressure in the main system 2, the fluid injected into the flow channel flows into the crack 11 under the action of positive pressure difference, the inflow volume and the inflow rate of the fluid are measured through a measuring system of the constant-pressure constant-speed pump until the indication number is not obviously changed, and the stage is the simulation of the natural fractured formation breathing effect drilling fluid leakage stage;
E. closing the constant-pressure constant-speed pump, opening a first valve 83 on the back pressure control system 8, enabling a flow channel of the back pressure control system 8 to be communicated, enabling fluid leaked into the fracture 11 to flow back into a high-pressure visual metering device 91 in the high-pressure visual metering system 9 under the action of pressure difference between the flowing pressure and the back pressure in the fracture 11, and metering the flowing volume and the flowing speed of the flowing back fluid through a camera device 92 until the flow meter display number in the high-pressure visual metering device 91 is not obviously changed, wherein the stage is the drilling fluid backflow stage simulation of the natural fracture stratum breathing effect.
The step A, B, C, D, E is a complete simulation of the respiration effect of the natural fracture formation, and the change rule of the key parameters of the respiration effect such as the loss/return rate and the accumulated loss along with the time can be obtained by recording the indication change.
It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims (10)

1. The drilling fluid is at the analogue means that fractured formation trace was taked in and send out, its characterized in that: the core injection device comprises a core (1) provided with a crack (11), a main body system (2) used for clamping the core (1) and pressurizing the core (1), wherein the main body system (2) is provided with an axial pressure loading cavity (3) used for axially pressurizing the core (1) and a confining pressure loading cavity (4) used for circumferentially pressurizing the core (1), and further comprises an injection system (5) used for injecting simulated wellbore fluid into the crack (11) of the core (1), an axial pressure injection control system (6) used for simulating formation confining pressure of the core (1), a confining pressure injection control system (7) used for simulating formation opening pressure of the crack (11), a back pressure control system (8) used for controlling pressure in a back-spitting stage and a high-pressure visual metering system (9) used for carrying out quantitative analysis on a breathing effect fluid back-spitting stage, wherein the injection system (5) is communicated with the crack (11) through a pipeline, the liquid injection control system (6) is connected with the shaft pressure loading cavity (3) through a pipeline, the confining pressure liquid injection control system (7) is connected with the confining pressure loading cavity (4) through a pipeline, the back pressure control system (8) is connected with the pipeline between the liquid injection system (5) and the crack (11), and the high-pressure visual metering system (9) is connected with the back pressure control system (8).
2. The drilling fluid stimulation device for the micro-throughput of a fractured formation according to claim 1, wherein the drilling fluid stimulation device comprises: the main body system (2) comprises an outer sleeve (21), a rigid sealing sleeve (22), an axial compression bearing end (23) and an axial compression loading end (24), wherein the core (1) is installed in the outer sleeve (21), the rigid sealing sleeve (22) is coated on the periphery of the core (1) and is positioned in the outer sleeve (21), a through hole is formed in the axial compression bearing end (23), the through hole is communicated with a crack (11) in the core (1), the axial compression bearing end (23) and the axial compression loading end (24) are arranged in the outer sleeve (21) and are respectively positioned on two sides of the rigid sealing sleeve (22), rubber sleeves (25) are installed on the axial compression bearing end (23), the rigid sealing sleeve (22) and the axial compression loading end (24), and a confining pressure loading cavity (4) is formed between the rubber sleeves (25) and the outer sleeve (21), and the axial pressure loading cavity (3) is formed between the axial pressure loading end (24) and the outer sleeve (21).
3. The drilling fluid stimulation device for the micro-throughput of a fractured formation according to claim 2, wherein the drilling fluid stimulation device comprises: the shaft pressure loading end (24) comprises a first connecting piece (241) and a sliding sleeve (242), wherein the first connecting piece (241) is connected with the rigid sealing sleeve (22), the first connecting piece (241) is connected with the sliding sleeve (242), the sliding sleeve (242) is in sliding connection with the outer sleeve (21), a convex ring (243) is arranged on the sliding sleeve (242), a boss (244) is arranged on the outer sleeve (21), and the convex ring (243), the sliding sleeve (242) and the boss (244) form the shaft pressure loading cavity (3).
4. The drilling fluid stimulation device for the micro-throughput of a fractured formation according to claim 2, wherein the drilling fluid stimulation device comprises: the liquid injection system (5) comprises a first liquid storage tank (51), a first liquid pump (52), a first pipeline (53) and a first pressure sensor (54) for monitoring the liquid pressure in the first pipeline (53), one end of the first pipeline (53) is connected with the first liquid storage tank (51), and the other end of the first pipeline is connected with the through hole; the first liquid pump (52) and the first pressure sensor (54) are mounted on the first pipe (53).
5. The drilling fluid stimulation device for the micro-throughput of a fractured formation according to claim 2, wherein the drilling fluid stimulation device comprises: the axial compression liquid injection control (6) system comprises a second liquid storage tank (61), a second liquid pump (62), a second pipeline (63) and a second pressure sensor (64) for monitoring the liquid pressure in the second pipeline (63), one end of the second pipeline (63) is connected with the second liquid storage tank (61), and the other end of the second pipeline (63) is connected with the axial compression loading cavity (3); the second pump (62) and the second pressure sensor (64) are mounted on a second conduit (63).
6. The drilling fluid stimulation device for the micro-throughput of a fractured formation according to claim 2, wherein the drilling fluid stimulation device comprises: the confining pressure liquid injection control system (7) comprises a third liquid storage tank (71), a third liquid pump (72), a third pipeline (73) and a third pressure sensor (74) for monitoring the liquid pressure in the third pipeline (73), one end of the third pipeline (73) is connected with the third liquid storage tank (71), and the other end of the third pipeline (73) is connected with the confining pressure loading cavity (4); the third liquid pump (72) and the third pressure sensor (74) are mounted on a third pipe (73).
7. The drilling fluid stimulation device for the micro-throughput of a fractured formation according to claim 2, wherein the drilling fluid stimulation device comprises: back pressure control system (8) include back pressure pump (81), back pressure valve (82), first valve (83) and fourth pipeline (84), back pressure pump (81), back pressure valve (82) and first valve (83) are linked together through fourth pipeline (84), first valve (83) are close to rock core (1) side, the one end of fourth pipeline (84) with annotate liquid system (5) and be linked together, the first port of back pressure valve (82) with first valve (83) link to each other, the second port of back pressure valve (82) with back pressure pump (81) link to each other, the third port of back pressure valve (82) with high pressure visual measurement system (9) are linked together.
8. The drilling fluid stimulation device for the micro-throughput of a fractured formation according to claim 7, wherein the drilling fluid stimulation device comprises: the high-pressure visual metering system (9) comprises a high-pressure visual metering device (91) and a camera device (92) for shooting data on the high-pressure visual metering device (91), and the high-pressure visual metering device (91) is communicated with a third port of the back-pressure valve (82).
9. A simulation method of a simulation device of drilling fluid micro-throughput in fractured formations according to any one of claims 1 to 8, characterized by comprising the following steps:
s1: matching the initial pressure of the back pressure control system (8) with the wellbore pressure near the simulated natural fracture (11) stratum based on the simulated natural fracture (11) stratum parameters;
s2: starting the axial pressure injection control system (6) and the confining pressure injection control system (7) to inject pressure to the main body system (2), so that the confining pressure is matched with the formation starting pressure of the natural fracture (11), and the axial pressure is matched with the formation confining pressure of the natural fracture (11);
s3: starting an injection system (5), setting the pressure as the simulated wellbore pressure, injecting liquid into the crack (11) of the core (1), increasing the injection pressure of the injection system (5) after the flow of the injection system (5) is not changed, enabling the flow passage pressure to exceed the stratum starting pressure of the simulated natural crack (11), and measuring the flow change by using a metering system of a pump in the injection system (5);
s4: and (3) closing the liquid injection system (5), opening a passage of a back pressure control system (8), and metering the flow change by using a high-pressure visual metering system (9).
10. The method for simulating the micro-throughput of drilling fluid in a fractured formation according to claim 9, wherein the steps S1 to S5 are repeated, and the initial pressure of the back pressure control system (8) is increased or the axial pressure of the axial pressure injection control system (6) is changed or the fluid pressure of the injection system (5) is changed.
CN202110963687.9A 2021-08-20 2021-08-20 Simulation device and simulation method for micro-huff and puff of drilling fluid in fractured stratum Pending CN113605885A (en)

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Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150041120A1 (en) * 2012-02-06 2015-02-12 M-I L.L.C. Modeling and analysis of hydraulic fracture propagation to surface from a casing shoe
CN107701160A (en) * 2017-09-30 2018-02-16 中国石油大学(华东) Simulate hydraulically created fracture and the experimental provision and method of intrinsic fracture extension influence
CN107741390A (en) * 2017-08-21 2018-02-27 中国石油大学(北京) The physical simulating method that water filling induces microcrack Extending Law is reproduced under formation condition
CN107907431A (en) * 2017-11-14 2018-04-13 中南大学 Three axis load pulses hydraulically created fracture extended dynamic monitoring test devices
CN109001438A (en) * 2017-06-06 2018-12-14 中国石油化工股份有限公司 A kind of joint seal gas shutoff experimental simulation device and test method
CN110146424A (en) * 2019-05-08 2019-08-20 中国石油大学(北京) The simulator and method of stratum cell breath
CN111101934A (en) * 2018-10-10 2020-05-05 中国石油化工股份有限公司 Method for evaluating damage of fracturing modification on reservoir
CN111337411A (en) * 2020-04-14 2020-06-26 中国石油天然气集团有限公司 Method and device for testing radial permeability of full-diameter shale
CN112610203A (en) * 2020-12-17 2021-04-06 中国石油大学(华东) Simulation device and method for natural fracture stratum respiration effect
CN113006759A (en) * 2021-03-16 2021-06-22 中国石油大学(华东) Shale oil fracturing synchronous energization simulation experiment device and method
CN213580870U (en) * 2020-11-11 2021-06-29 长江大学 Crack dynamic simulation plugging experimental device

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150041120A1 (en) * 2012-02-06 2015-02-12 M-I L.L.C. Modeling and analysis of hydraulic fracture propagation to surface from a casing shoe
CN109001438A (en) * 2017-06-06 2018-12-14 中国石油化工股份有限公司 A kind of joint seal gas shutoff experimental simulation device and test method
CN107741390A (en) * 2017-08-21 2018-02-27 中国石油大学(北京) The physical simulating method that water filling induces microcrack Extending Law is reproduced under formation condition
CN107701160A (en) * 2017-09-30 2018-02-16 中国石油大学(华东) Simulate hydraulically created fracture and the experimental provision and method of intrinsic fracture extension influence
CN107907431A (en) * 2017-11-14 2018-04-13 中南大学 Three axis load pulses hydraulically created fracture extended dynamic monitoring test devices
CN111101934A (en) * 2018-10-10 2020-05-05 中国石油化工股份有限公司 Method for evaluating damage of fracturing modification on reservoir
CN110146424A (en) * 2019-05-08 2019-08-20 中国石油大学(北京) The simulator and method of stratum cell breath
CN111337411A (en) * 2020-04-14 2020-06-26 中国石油天然气集团有限公司 Method and device for testing radial permeability of full-diameter shale
CN213580870U (en) * 2020-11-11 2021-06-29 长江大学 Crack dynamic simulation plugging experimental device
CN112610203A (en) * 2020-12-17 2021-04-06 中国石油大学(华东) Simulation device and method for natural fracture stratum respiration effect
CN113006759A (en) * 2021-03-16 2021-06-22 中国石油大学(华东) Shale oil fracturing synchronous energization simulation experiment device and method

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
刘四海 等: "裂缝性岩样应力敏感性实验研究", 钻采工艺, vol. 34, no. 06, 31 December 2011 (2011-12-31), pages 14 - 15 *
王克杰 等: "新庄油田断层临界开启压力研究与应用", 石油天然气学报, no. 04, 31 August 2008 (2008-08-31), pages 57 - 60 *

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