CN107339097B

CN107339097B - Leak stoppage evaluation device and method

Info

Publication number: CN107339097B
Application number: CN201710670693.9A
Authority: CN
Inventors: 张艳娜; 陶冶; 石李保
Original assignee: Petrochina Co Ltd
Current assignee: Petrochina Co Ltd
Priority date: 2017-08-08
Filing date: 2017-08-08
Publication date: 2020-08-11
Anticipated expiration: 2037-08-08
Also published as: CN107339097A

Abstract

The application provides a leaking stoppage evaluation device, it includes: the device comprises a simulated formation mechanism, a simulated shaft mechanism, a liquid inlet channel, a circulating channel and a measuring device. The simulated formation mechanism is provided with an inner cavity for accommodating the leakage module. The simulated shaft mechanism is provided with an input channel extending vertically and a backflow channel communicated with the bottom of the input channel, and the backflow channel is communicated with the inner cavity. The liquid inlet channel is communicated with the input channel so as to input the leakage stoppage slurry with the preset temperature into the input channel, and the leakage stoppage slurry is used for plugging the leakage module. The circulation channel is communicated with the backflow channel and the liquid inlet channel, and a first pump is arranged on the circulation channel so that the leakage-stopping slurry can circularly flow in the backflow channel, the circulation channel and the liquid inlet channel. The measuring device is communicated with the inner cavity and is used for measuring the weight of the plugging slurry flowing out of the leakage module after the leakage module is plugged. In addition, the invention also provides a leaking stoppage evaluation method, which can simulate a dynamic leaking stoppage process and a static leaking stoppage process.

Description

Leak stoppage evaluation device and method

Technical Field

The application belongs to the technical field of oil exploitation, and particularly relates to a leakage stoppage evaluation device and method.

Background

Lost circulation generally refers to a complex downhole condition in which various working fluids (including drilling fluids, cement slurries, completion fluids, and other fluids) directly enter the formation under the action of a pressure differential during downhole operations such as drilling, cementing, testing, or workover. Lost circulation has been a problem in the drilling industry, and along with the development of drilling technology, lost circulation technology is also continuously developed. But the uncertainty of the underground leaking layer position and the uncertainty of the leaking channel sometimes result in low success rate of plugging. The imperfection of the indoor evaluation device is a key problem which restricts the technical development of the plugging process and the plugging material. Therefore, an evaluation device capable of effectively simulating an underground leaking layer and a leaking state can greatly promote the progress of the leaking stoppage technology.

Chinese utility model patent document CN204877451U discloses an annular core drilling leaking stoppage simulation evaluation device. The device includes: the liquid inlet system, inner skleeve, outer skleeve, annular rock core, agitating unit and play liquid system. The liquid outlet of the liquid inlet system is communicated with the inner cavity of the inner sleeve, the inner sleeve is arranged in the outer sleeve, and a backflow gap is formed between the outer peripheral wall of the inner sleeve and the inner peripheral wall of the outer sleeve. The upper part of the outer peripheral wall of the inner sleeve is provided with a backflow through hole communicated with the backflow gap, and the bottom of the inner sleeve is communicated with the inner cavity of the outer sleeve. The outer sleeve is of a closed structure, the annular rock core is arranged in the peripheral wall of the outer sleeve, and the inner peripheral wall of the annular rock core and the inner peripheral wall of the outer sleeve are located on the same cylindrical peripheral surface. Stirring device's stirring vane sets up in the sleeve, can rotate and drive the downward motion of shutoff slurry. The liquid inlet of the liquid outlet system is communicated with the peripheral wall of the annular rock core. The device can enable the plugging slurry to move downwards to pass through the inner sleeve and then move upwards along the backflow gap to flow through the inner surface of the annular core to perform plugging under the rotating action of the stirring blades. Although the patent can simulate the flowing state of plugging slurry on site, the annular core of the evaluation device needs to be arranged in the peripheral wall of the outer sleeve, so that the operation process is complex and is not easy to implement when the core is placed and taken out.

Disclosure of Invention

Because the upper cover of the leakage stoppage simulation evaluation device in the prior art must be opened, and the magnetic stirrers in the inner sleeve and the inner sleeve are taken out, the operation of placing and taking out the rock core can be carried out. In order to overcome the above defects in the prior art, the invention provides a leak stoppage evaluation device and method, which can simulate a dynamic leak stoppage process and a static leak stoppage process by a test method so as to perform leak stoppage simulation on the leak stoppage conditions in the drilling and stopping processes. Compared with the simulation evaluation device in the prior art, the evaluation device is convenient and easy to operate when the leakage module is placed.

The specific technical scheme of the invention is as follows:

the invention provides a leak stoppage evaluation device, comprising:

the stratum simulation mechanism is provided with an inner cavity for accommodating the leakage module;

the simulated shaft mechanism with the preset pressure is provided with an input channel extending vertically and a backflow channel communicated with the bottom of the input channel, and the backflow channel is communicated with the inner cavity;

the liquid inlet channel is communicated with the input channel so as to input plugging slurry with preset temperature into the input channel, and the plugging slurry is used for plugging the leakage module;

the circulation channel is communicated with the backflow channel and the liquid inlet channel, and a first pump is arranged on the circulation channel so that the leakage-stopping slurry can circularly flow in the backflow channel, the circulation channel and the liquid inlet channel;

and the measuring device is communicated with the inner cavity and is used for measuring the weight of the leakage-stopping slurry flowing out of the leakage-stopping module after the leakage-stopping module is stopped.

In one embodiment, the simulated wellbore mechanism comprises an inner cylinder, and a simulated cylinder surrounding a portion of the inner cylinder along a circumferential direction of the inner cylinder; the input channel is formed in the inner cylinder; the simulation cylinder is provided with a first end and a second end along the circumferential direction, and the backflow channel is formed between the first end and the second end.

In one embodiment, the simulator tube is surrounded by an outer tube, and the return flow channel is located between the inner tube and the outer tube.

In one embodiment, the formation simulation mechanism is provided with a plurality of first pressure sensors for measuring the pressure of the loss module, and the first pressure sensors are arranged along the loss extending direction of the loss module.

In one embodiment, a first stop valve is arranged on the circulation channel, and a second stop valve is arranged on the liquid inlet channel.

In one embodiment, the plugging evaluation device further comprises a liquid preparation container and a pressurizing device, wherein the liquid preparation container is used for providing plugging slurry into the liquid inlet channel, and the pressurizing device is used for applying preset pressure into the simulated shaft mechanism.

In one embodiment, the pressurizing means comprises a second pump and a pressure regulator, between which a second pressure sensor is arranged.

In one embodiment, a heater is disposed on the liquid inlet channel and/or the circulation channel, and the heater is used for heating the plugging slurry to a predetermined temperature.

In one embodiment, the measuring device comprises a condenser and a weight measuring device, the condenser is used for condensing the leakage stoppage slurry flowing out of the leakage module after the leakage module is plugged, and the weight measuring device is used for measuring the weight of the condensed leakage stoppage slurry.

In one embodiment, the simulated wellbore mechanism includes a dump valve disposed in a lower portion of the simulated wellbore mechanism and an exhaust valve disposed in an upper portion of the simulated wellbore mechanism.

In one embodiment, an agitator is provided within the inlet channel for agitating the plugging slurry within the inlet channel.

In addition, the application also provides an evaluation method of the leakage stoppage evaluation device, which comprises the following steps:

applying a predetermined pressure into an input channel of the simulated wellbore mechanism;

the second stop valve is opened, and plugging slurry with preset temperature is input into the input channel;

the first stop valve and the first pump are opened, and the second stop valve is closed, so that the leakage-stopping slurry circularly flows in the backflow channel, the circulation channel and the liquid inlet channel and flows to the simulated formation mechanism through the backflow channel, and a leakage module in the simulated formation mechanism is blocked;

within a preset time, the measuring device measures the weight of the leaking stoppage slurry flowing out of the leaking stoppage module after the leaking stoppage module is plugged, and the weight of the leaking stoppage slurry is obtained;

and evaluating the plugging effect according to the weight of the plugging slurry flowing out of the leakage module after plugging the leakage module.

The method for evaluating a leak stoppage evaluating device according to another embodiment includes:

closing the first stop valve, the second stop valve and the first pump to enable the plugging slurry to flow to the simulated formation mechanism through the backflow channel so as to plug a leakage module in the simulated formation mechanism;

In one embodiment, the method comprises: the first pressure sensor tests the pressure in the leakage module and determines the position of the effective blocking layer according to the pressure.

Borrow by above technical scheme, the beneficial effect of this application lies in: the leakage stoppage evaluation device and method can provide a circulation route of leakage stoppage slurry with preset pressure and preset temperature, well conditions including underground temperature, pressure and flow state of the leakage stoppage slurry can be simulated, and leakage stoppage simulation is carried out by establishing different leakage modules, leakage conditions of drilling engineering and the like. The plugging evaluation device and the method can optimize the type and the proportion of the plugging material, and evaluate the temperature resistance of the plugging material, the pressure bearing capacity after plugging and the like. The method researches the plugging effect of different plugging materials on various lost formations, and provides a complete and effective experimental basis for plugging the lost formations in the drilling engineering and correctly processing the loss accidents in the drilling engineering.

Specific embodiments of the present application are disclosed in detail with reference to the following description and drawings, indicating the manner in which the principles of the application may be employed. It should be understood that the embodiments of the present application are not so limited in scope. The embodiments of the application include many variations, modifications and equivalents within the spirit and scope of the appended claims.

Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments, in combination with or instead of the features of the other embodiments.

It should be emphasized that the term "comprises/comprising" when used herein, is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps or components.

Drawings

The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. In addition, the shapes, the proportional sizes, and the like of the respective members in the drawings are merely schematic for assisting the understanding of the present application, and are not particularly limited to the shapes, the proportional sizes, and the like of the respective members in the present application. Those skilled in the art, having the benefit of the teachings of this application, may select various possible shapes and proportional sizes to implement the present application, depending on the particular situation. In the drawings:

fig. 1 is a schematic structural view of a leak stoppage evaluating apparatus according to an embodiment of the present application;

fig. 2 is a sectional view of a simulated formation mechanism and a simulated wellbore mechanism in the leak stoppage evaluating apparatus according to the embodiment of the present application;

fig. 3 is a flowchart of a dynamic leak stoppage evaluation method according to an embodiment of the present application;

fig. 4 is a flowchart of a static leak stoppage evaluation method according to an embodiment of the present application.

Reference numerals of the above figures: 1. an input channel; 2. a simulated wellbore mechanism; 3. a simulated formation mechanism; 4. a measuring device; 5. a liquid preparation container; 6. a second stop valve; 7. a first pump; 8. a second pump; 9. a pressure regulator; 10. a second pressure sensor; 11. a liquid inlet channel; 12. a circulation channel; 13. an inner barrel; 14. a simulation cylinder; 15. an outer cylinder; 16. a return flow channel; 17. a loss module; 18. a first pressure sensor; 19. a first end; 20. a condenser; 21. a second end; 22. a weight measuring device; 23. a first shut-off valve; 25. an atmospheric valve; 26. an exhaust valve; 27. heating device

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art without any inventive work based on the embodiments in the present application are within the scope of protection of the present application.

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The invention provides a leak stoppage evaluating device, which comprises: the device comprises a simulated formation mechanism 3, a simulated well bore mechanism 2, a liquid inlet channel 11, a circulating channel 12 and a measuring device 4. The simulated formation mechanism 3 has an inner cavity for receiving the thief module 17. The simulated shaft mechanism 2 is provided with an input channel 1 extending vertically and a backflow channel 16 communicated with the bottom of the input channel 1, and the backflow channel 16 is communicated with the inner cavity. The liquid inlet channel 11 is communicated with the input channel 1 so as to input plugging slurry with a preset temperature into the input channel 1, and the plugging slurry is used for plugging the leakage module 17. Circulation path 12 with return flow path 16 with inlet channel 11 is linked together, be provided with first pump 7 on the circulation path 12, so that the leaking stoppage thick liquid can return flow path 16 circulation path 12 and inlet channel 11 inner loop flows. The measuring device 4 is communicated with the inner cavity and is used for measuring the weight of the plugging slurry flowing out of the leakage module 17 after the leakage module 17 is plugged.

When the leakage stoppage evaluating device is used, leakage stoppage slurry with preset temperature is input into the input channel 1 with preset pressure from the liquid inlet channel 11, and the leakage stoppage slurry can circularly flow in the backflow channel 16, the circulating channel 12 and the liquid inlet channel 11 to simulate a dynamic leakage stoppage process. It is also possible to simulate the static plugging process with flow only in the return channel 16. The leakage stopping slurry can block the leakage stopping module 17 in the simulated formation mechanism 3 in the flowing process of the leakage stopping slurry, and the weight of the leakage stopping slurry flowing out of the leakage stopping module 17 after the leakage stopping module 17 is blocked is measured by the measuring device 4 in preset time. And evaluating the plugging effect of the plugging slurry according to the weight of the plugging slurry flowing out of the leakage module 17 after the leakage module 17 is plugged. Specifically, the smaller the weight of the plugging slurry measured by the measuring device is within the preset time, the better the plugging effect of the plugging slurry is proved.

The leakage stoppage evaluation device can provide a circulation route of leakage stoppage slurry with preset pressure and preset temperature, can simulate well conditions including underground temperature, pressure and flow state of the leakage stoppage slurry, and performs leakage stoppage simulation by establishing different leakage modules 17, leakage conditions of drilling engineering and the like. The plugging evaluation device can optimize the type and the proportion of the plugging material, and evaluate the temperature resistance of the plugging material, the pressure bearing capacity after plugging and the like. The method researches the plugging effect of different plugging materials on various lost formations, and provides a complete and effective experimental basis for plugging the lost formations in the drilling engineering and correctly processing the loss accidents in the drilling engineering.

In the present embodiment, the simulated formation mechanism 3 has an internal cavity in which the thief module 17 can be accommodated. The leakage module 17 may be a crack type module, a porous type module, or a sand-filled type module according to different requirements of actual tests, which is not limited in this application. The formation simulator 3 is preferably a gripper, which can adjust the tightness of the grip of the gripper according to the size, thickness, etc. of the drop-out module 17.

The simulated shaft mechanism 2 can be provided with an input channel 1 and a return channel 16 which extend vertically, in a normal condition, the input channel 1 and the return channel 16 can be arranged in parallel, and the bottom of the input channel 1 is communicated with the return channel 16, so that the plugging slurry flowing in the input channel 1 flows into the return channel 16 through the bottom of the input channel, and the dynamic plugging process of the plugging slurry is simulated.

The backflow channel 16 may be in communication with the inner cavity of the simulated formation mechanism 3, so that the plugging slurry may flow into the inner cavity of the simulated formation mechanism 3 through the backflow channel 16, thereby plugging the leakage module 17 in the inner cavity. The inlet channel 11 may typically be a pipe, which communicates with the inlet channel 1 for feeding plugging slurry with a predetermined temperature into said inlet channel 1. It will be appreciated that the input channel 1 is to have a predetermined pressure to simulate the pressure in the wellbore. The specific pressure level may be comparable to the pressure in the actual wellbore, and the application is not limited in this regard.

The circulation channel 12 is usually arranged outside the simulated borehole means 2, and the first pump 7 is arranged on the circulation channel 12. The first pump 7 may be a circulation pump which circulates the plugging slurry in the return channel 16, the circulation channel 12, and the liquid inlet channel 11. The process of the circulation flow of the plugging slurry simulates the process that the plugging slurry enters a shaft along a drill rod, then returns to the ground along the underground annular space and plugs a lost stratum in the returning process, namely the dynamic plugging is simulated.

The measuring device 4 may be in communication with the inner cavity of the simulated formation mechanism 3. The measuring device 4 is used for measuring the weight of the leaking stoppage slurry flowing out of the leaking stoppage module 17 after the leaking stoppage module 17 is plugged, so that the leaking stoppage performance of the leaking stoppage slurry is evaluated. In particular, the measuring device 4 may be a balance, and the less leaking stoppage slurry flows out from the leaking stoppage module 17 after plugging, the better the leaking stoppage effect in a predetermined time. The predetermined time may be set according to actual needs, and the present application does not limit this.

Specifically, the simulated wellbore apparatus 2 may include an inner cylinder 13 and a simulated cylinder 14, and the inner cylinder 13 may form the input channel 1 inside. The dummy cylinder 14 may surround a part of the inner cylinder 13 in a circumferential direction of the inner cylinder 13, and preferably, the dummy cylinder 14 may surround substantially 2/3 of the inner cylinder 13. The simulator cartridge 14 has a first end 19 and a second end 21 in the circumferential direction, the first end 19 and the second end 21 defining the return flow path 16 therebetween, whereby the return flow path 16 surrounds approximately 1/3 of the inner cartridge 13.

Preferably, the dummy cartridge 14 may also be surrounded by the outer cartridge 15 such that the return flow path 16 is between the inner cartridge 13, the outer cartridge 15, and the first end 19 and the second end 21 of the dummy cartridge 14. In this way, the plugging slurry flowing from the input channel 1 to the return channel 16 generates a larger pressure due to the smaller return channel 16, so as to better plug the leakage module 17 in the simulated formation mechanism 3. On the other hand, because the plugging slurry in the backflow channel 16 has higher pressure, the flow rates of the first pump 7 and the second pump 8 of the plugging evaluation device are not required to be too high, so that the pressure of the first pump 7 and the pressure of the second pump 8 are not required to be too high, and the safety of the test is ensured. Preferably, in order to ensure the temperature and pressure inside the simulated wellbore device 2, the outer cylinder 15 may be provided with a heating jacket and/or a sealing jacket.

In a preferred embodiment, the simulated formation mechanism 3 may be provided with a plurality of first pressure sensors 18 for measuring the pressure of the loss module 17. The number of the first pressure sensors 18 may be determined according to the length of the drop-out module 17, which is not limited in any way by the present application. Preferably, the first pressure sensor 18 may be arranged along the leakage extension direction of the leakage module 17. In a normal case, the first pressure sensors 18 may be disposed at the front, middle, and rear of the loss module 17 in the direction of the loss extension of the loss module 17. Therefore, the first pressure sensor 18 can test the pressure of different positions of the leakage module 17, the position where effective plugging occurs is accurately reflected, the particle set matching of the plugging material can be adjusted accordingly, and proper plugging slurry is selected.

In another embodiment, a first stop valve 23 is provided on the circulation channel 12, and a second stop valve 6 is provided on the liquid inlet channel 11. When the dynamic plugging process is simulated, the first stop valve 23 and the first pump 7 can be opened, so that the plugging slurry circularly flows in the backflow channel 16, the circulating channel 12 and the liquid inlet channel 11, and the leakage module 17 is plugged. When the static plugging process is simulated, the first stop valve 23, the second stop valve 6 and the first pump 7 can be closed, the plugging slurry in the liquid inlet channel 11 and the input channel 1 is kept, and the plugging slurry blocks the leakage module 17 through the backflow channel 16, so that the plugging condition after the drill is stopped or pulled out is simulated.

Further, the leak stoppage evaluating device may further include a liquid preparation container 5 and a pressurizing device. The liquid distribution container 5 may be a bottle or a tank for containing plugging slurry, and is used for supplying the plugging slurry into the liquid inlet channel 11. The pressurizing means may apply a predetermined pressure into the simulated wellbore apparatus 2 so as to simulate the pressure in the wellbore of the oil well during actual operation. In particular, the pressurizing means may comprise a second pump 8 and a pressure regulator 9. Wherein the second pump 8 is preferably a constant pressure pump and the pressure regulator 9 is adapted to regulate the pressure in the simulated wellbore arrangement 2. Preferably, a second pressure sensor 10 may be provided between the second pump 8 and the pressure regulator 9 to monitor the pressure in the simulated wellbore device 2 in real time to meet the actual demand.

In order to ensure a simulated downhole temperature so that the plugging slurry can flow, a heater 27 is provided on the liquid inlet channel 11 and/or the circulation channel 12, and the heater 27 is used for heating the plugging slurry to a predetermined temperature. The predetermined temperature may be the temperature at the actual well, and the application is not limited in any way. Meanwhile, in order to keep the plugging slurry in a flowing state, a stirrer (not shown in the figure) can be arranged in the input channel 1 and is used for stirring the plugging slurry in the input channel 1.

In addition, the measuring device 4 of the evaluation device for simulating a leak may include a condenser 20 and a weight scale 22. Because the simulated shaft mechanism 2 has higher temperature and higher pressure, the leakage stoppage slurry flowing out of the simulated formation mechanism 3 can not be measured due to the fact that high temperature and high pressure are in a gas state, the leakage stoppage slurry with high temperature and high pressure is cooled into a liquid state through the condenser 20 before the weight measurer 22 measures the leakage stoppage slurry with high temperature and high pressure, and then the weight of the leakage stoppage slurry after cooling is measured, so that the operation is safer and more reliable.

Because the simulated leaking stoppage evaluation test is carried out under high pressure, in order to ensure the safe operation when each test part or mechanism is disassembled after the test is finished, the simulated shaft mechanism 2 can also be provided with an air release valve 25 and an exhaust valve 26, wherein the air release valve 25 is arranged at the lower part of the simulated shaft mechanism 2 and is used for discharging residual leaking stoppage slurry in the leaking stoppage evaluation device. The exhaust valve 26 is arranged at the upper part of the simulated borehole mechanism 2 and is used for exhausting high-pressure gas in the simulated borehole mechanism 2.

In addition, the invention also provides an evaluation method of the leakage stoppage evaluation device, which comprises a dynamic simulation method and a static simulation method. The dynamic simulation method is described below:

s101: firstly, applying preset pressure to the input channel 1 of the simulated shaft mechanism 2 by using a pressurizing device;

s102: and the second stop valve 6 is opened, and plugging slurry with preset temperature is input into the input channel 1.

S103: and then, opening the first stop valve 23 and the first pump 7, closing the second stop valve 6, and enabling the leaking stoppage slurry to circularly flow in the backflow channel 16, the circulating channel 12 and the liquid inlet channel 11 and reach the simulated formation mechanism 3 through the backflow channel 16 to block the leaking stoppage module 17 in the simulated formation mechanism 3.

S104: within a preset time, the measuring device 4 measures the weight of the leaking stoppage slurry flowing out of the leaking stoppage module 17 after the leaking stoppage module 17 is blocked, and the weight of the leaking stoppage slurry is obtained.

S105: and finally, evaluating the plugging effect according to the weight of the plugging slurry flowing out of the leakage module 17 after the leakage module 17 is plugged.

The static plugging process of the plugging slurry is similar to the dynamic plugging process, and comprises the following steps:

s201: a predetermined pressure is applied to the input channel 1 of the simulated wellbore apparatus 2 by a pressurizing device.

S202: and the second stop valve 6 is opened, and plugging slurry with preset temperature is input into the input channel 1.

S203: then the first stop valve 23, the second stop valve 6 and the first pump 7 are closed, and the plugging slurry is delivered to the simulated formation mechanism 3 through the return channel 16 to plug the leakage module 17 in the simulated formation mechanism 3.

S204: within a preset time, the measuring device 4 measures the weight of the leaking stoppage slurry flowing out of the leaking stoppage module 17 after the leaking stoppage module 17 is blocked, and the weight of the leaking stoppage slurry is obtained.

S205: and finally, evaluating the plugging effect according to the weight of the plugging slurry flowing out of the leakage module 17 after the leakage module is plugged.

In addition, the leak stoppage evaluating method can also test the pressure in the leak-off module 17 by using the first pressure sensor 18, and determine the position of the effective plugging layer according to the pressure. Specifically, the position of the blocking layer may be determined according to the magnitude of the pressure on the first pressure sensor 18, and the position where the pressure is highest is the position of the blocking layer. Preferably, the blocking layer is to be formed at the leading middle of the drop-out module.

It should be noted that any suitable existing structure may be used for the shutoff valve, the pressure sensor, the condenser, and the like provided in the present embodiment. For clearly and briefly explaining the technical solution provided by the present embodiment, the above parts will not be described again, and the drawings in the specification are also simplified accordingly. It should be understood, however, that the present embodiments are not limited in scope thereby.

All articles and references disclosed, including patent applications and publications, are hereby incorporated by reference for all purposes. The term "consisting essentially of …" describing a combination shall include the identified element, ingredient, component or step as well as other elements, ingredients, components or steps that do not materially affect the basic novel characteristics of the combination. The use of the terms "comprising" or "including" to describe combinations of elements, components, or steps herein also contemplates embodiments that consist essentially of such elements, components, or steps. By using the term "may" herein, it is intended to indicate that any of the described attributes that "may" include are optional.

It is to be understood that the above description is intended to be illustrative, and not restrictive. Many embodiments and many applications other than the examples provided will be apparent to those of skill in the art upon reading the above description. The scope of the present teachings should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are hereby incorporated by reference for all purposes. The omission in the foregoing claims of any aspect of subject matter that is disclosed herein is not intended to forego the subject matter and should not be construed as an admission that the applicant does not consider such subject matter to be part of the disclosed subject matter.

Claims

1. A leak stoppage evaluating device, comprising:

the measuring device is communicated with the inner cavity and is used for measuring the weight of the leaking stoppage slurry flowing out of the leaking stoppage module after the leaking stoppage module is stopped;

the simulated shaft mechanism comprises an inner cylinder and a simulated cylinder which surrounds part of the inner cylinder along the circumferential direction of the inner cylinder; the input channel is formed in the inner cylinder; the simulation cylinder is provided with a first end and a second end along the circumferential direction, and the backflow channel is formed between the first end and the second end.

2. A leak stoppage evaluating device according to claim 1, wherein the simulating cylinder is surrounded by an outer cylinder, and the backflow passage is located between the inner cylinder and the outer cylinder.

3. Leak stoppage evaluation device according to claim 1, wherein a plurality of first pressure sensors for measuring the pressure of the loss module are provided on the simulated formation mechanism, and the first pressure sensors are arranged along the loss extending direction of the loss module.

4. Leak stoppage evaluation device according to claim 1, wherein a first stop valve is provided on the circulation passage, and a second stop valve is provided on the liquid inlet passage.

5. A leak stoppage evaluating apparatus according to claim 1, further comprising a liquid preparation vessel for supplying a leak stoppage slurry into the liquid inlet passage and a pressurizing means for applying a predetermined pressure into the simulated wellbore structure.

6. Leak stoppage evaluation device according to claim 5, wherein the pressurizing device comprises a second pump and a pressure regulator, and a second pressure sensor is provided between the second pump and the pressure regulator.

7. Leak stoppage evaluating device according to claim 1, wherein a heater is provided on the liquid feeding passage and/or the circulation passage, the heater being for heating the leak stoppage slurry to a predetermined temperature.

8. A leak stoppage evaluation device according to claim 1, wherein the measuring device includes a condenser for condensing the leak stoppage slurry flowing out of the leak stoppage module after the leak stoppage module is closed, and a weight measuring instrument for measuring the weight of the condensed leak stoppage slurry.

9. Leak stoppage evaluation device according to claim 1, wherein the simulated wellbore mechanism includes a relief valve and an exhaust valve, the relief valve being provided at a lower portion of the simulated wellbore mechanism, the exhaust valve being provided at an upper portion of the simulated wellbore mechanism.

10. A leak stoppage evaluating device according to claim 1, wherein an agitator is provided in the input passage, the agitator being for agitating the leak stoppage slurry in the input passage.

11. An evaluation method of a leak stoppage evaluation device according to any one of claims 1 to 10, comprising:

12. An evaluation method of a leak stoppage evaluation device according to any one of claims 1 to 10, comprising:

13. The evaluation method of a leak stoppage evaluation device according to claim 11 or 12, comprising: the first pressure sensor tests the pressure in the leakage module and determines the position of the effective blocking layer according to the pressure.