CN118029943A - Super-elastic metal sealing mechanism for packer and sealing performance testing device - Google Patents

Abstract

The invention discloses a super-elastic metal sealing mechanism for a packer and a sealing performance testing device, wherein the sealing mechanism comprises a main oil pipe, a central oil pipe and a slip assembly, and the outer diameter of the central oil pipe is provided with an elastic sealing assembly; the elastic sealing assembly comprises a conical wedge block and a metal elastic sealing element provided with a conical groove. The sealing performance testing device comprises a testing bench assembly, a testing container, a testing connecting pipe, a testing central pipe, a slip assembly, an elastic sealing assembly and a packer control assembly. The beneficial effects are that: the super-elastic metal sealing mechanism can realize reliable sealing between the main oil pipe and the central oil pipe through the cooperation of the conical wedge block and the conical groove of the metal elastic sealing piece, and has a simple, stable and reliable structure; the sealing performance testing device can further simulate the sealing performance of the sealing mechanism under the environment of high temperature and high pressure in the pit, truly simulate the actual working condition, further improve the testing accuracy, and intuitively judge the sealing performance of the elastic sealing assembly.

Description

A superelastic metal sealing mechanism for packer and sealing performance testing device

Technical Field

The invention relates to a sealing mechanism and a sealing test device thereof, in particular to a superelastic metal sealing mechanism for a packer and a sealing performance test device thereof, belonging to the technical field of oil production equipment.

Background technique

The main functions of the packer in oil production are stratified oil production, well washing, water injection, fracturing and acidizing. Its sealing performance plays a key role in the performance of the packer. In order for the packer to work normally underground, it is necessary to test it on the well before deploying it underground.

There are many types of test devices for testing the performance of packers, but most of them are mainly used to test the sealing performance of packers, without considering the sealing performance of packers at high temperatures, and the connection between structures is cumbersome and time-consuming, which affects the efficiency of packer experimental testing. With the continuous development of oil exploration and development, oilfield exploitation is increasingly tending to deep wells with high temperature, high pressure and high corrosion. Packers are often sealed with rubber materials (rubber cylinders), which often fail due to high temperature, high pressure and corrosion, resulting in stagnation of downhole operations, affecting the production efficiency of oilfields and causing serious economic losses.

Chinese patent CN108952619B discloses a mechanically set sand-proof tail pipe top packer, which includes a body, a composite sealing cylinder, an expansion upper assembly, a seat cone sleeve, an annular slip, a reverse tooth self-locking ring, an expansion lower assembly, a straightening ring and a casing coupling; a composite sealing cylinder is sleeved on the middle outer wall of the body. The sealing performance of this scheme is mainly achieved by compressing the composite sealing cylinder, so that the composite sealing cylinder expands and contacts the pipe wall to achieve sealing, and the sealing performance depends on the sealing material and the compression amount.

Chinese patent CN116816299A discloses an all-metal sealing packer and a method for predicting sealing performance and structural strength. Under the action of axial sealing force or radial liquid pressure, the middle of the metal sealing tube bulges, contacts the casing and generates a large contact stress to achieve sealing. This expansion structure has high requirements on the stability of the axial sealing force and radial liquid pressure, and has a long axial length, which will affect the applicability of the sealing device. The prediction method for sealing performance and structural strength cannot directly obtain the true values of sealing performance and structural strength, and due to the problem of processing accuracy, there will be individual differences in the sealing device, and it is impossible to truly simulate the actual working conditions of the sealing device underground, which may lead to safety hazards.

There are solutions in the prior art to replace the rubber sealing structure with a non-metallic composite sealing structure or a metal sealing structure, but the commonly used expansion principle will have certain reliability problems, and the core of the packer lies in the sealing device. Therefore, it is necessary to test the sealing performance of each sealing device before use, and it is necessary to truly simulate the actual temperature and pressure values for testing.

Summary of the invention

Purpose of the invention: The purpose of the present invention is to provide a superelastic metal sealing mechanism for a packer and a sealing performance testing device in view of the problems existing in the prior art.

Technical solution: A superelastic metal sealing mechanism for a packer, comprising a main oil pipe, a center oil pipe and a slip assembly, wherein the center oil pipe is located inside the main oil pipe, and the slip assembly is installed on the outer diameter of the center oil pipe and is located inside the main oil pipe; an elastic sealing assembly is provided on the outer diameter of the center oil pipe, and the elastic sealing assembly is located above the slip assembly; the elastic sealing assembly comprises a conical wedge and a metal elastic seal with a conical groove, wherein the metal elastic seal is sealed and fixedly connected to the outer wall of the center oil pipe, the conical wedge cooperates with the conical groove of the metal elastic seal, the conical wedge moves relative to the metal elastic seal along the axial direction of the center oil pipe, and the outer diameter taper of the conical wedge is greater than the inner taper of the conical groove of the metal elastic seal; when the conical wedge is subjected to force to squeeze one side of the metal elastic seal, the conical groove of the metal elastic seal is stretched open and its outer edge fits the inner wall of the main oil pipe; when the conical wedge no longer squeezes the metal elastic seal, the conical groove of the metal elastic seal is reset, and its outer edge is separated from the inner wall of the main oil pipe.

The present invention can achieve reliable sealing between the main oil pipe and the central oil pipe by cooperating with the tapered groove of the tapered wedge block and the metal elastic seal, and the structure is simple, stable and reliable; and the high-temperature resistant superelastic metal seal replaces the conventional rubber cylinder seal, thereby improving the high-temperature and high-pressure resistance of the seal, and the superelastic metal seal is reusable, thereby reducing the operation and maintenance cost of downhole tools for oil production.

Preferably, in order to further improve the sealing performance, the outer edge of the tapered groove of the metal elastic seal is provided with a cylindrical elastic sealing portion. The cylindrical structure can increase the effective sealing area, and the elastic sealing portion can form a more reliable seal with the rigid inner wall of the main oil pipe.

Preferably, in order to truly simulate the working conditions downhole and thus accurately detect the sealing performance of the sealing mechanism, a sealing performance test device for a superelastic metal sealing mechanism for a packer includes a test bench assembly, a test container, a test connecting pipe, a test center pipe, a slip assembly, an elastic sealing assembly and a packer control assembly.

The test center pipe comprises a test center inner pipe and a test center outer pipe, wherein the test center inner pipe is a tubular structure with a closed bottom, the top of the test center inner pipe is connected to the test connecting pipe through a packer control assembly and is internally connected, the slip assembly is installed on the outer wall of the lower end of the test center inner pipe, the test center outer pipe is sleeved on the outer diameter of the test center inner pipe and is connected to the slip assembly in the axial direction; the metal elastic seal is sealed and fixedly connected to the outer wall of the test center outer pipe;

A test oil connecting pipe is provided at the bottom of the test container, and the test center pipe together with the slip assembly, the elastic sealing assembly and the packer control assembly are installed inside the test container, and during the setting test, the slip assembly and the elastic sealing assembly are in contact with the inner wall of the test container respectively;

A driving oil connecting pipe communicating with the interior is provided on the upper part of the test connecting pipe, the test connecting pipe passes through the top of the test container and is communicated with the inner pipe of the test center through the packer control assembly, the test connecting pipe is sealedly connected to the test container, and the driving oil connecting pipe is located outside the test container;

The test container is detachably mounted on the test bench assembly along a vertical direction.

The sealing performance testing device of the present invention is implemented by respectively installing the elastic sealing component and the cava component to be tested on the test center pipe, and then sealingly installing the installed test center pipe inside the test container, and controlling the cava component through the packer control component to complete the simulation of the sealing of the elastic sealing component, and finally injecting high-pressure oil into the test container from the test oil connecting pipe at the bottom of the test container to simulate the high-pressure state downhole; the bottom of the test center inner pipe is a closed structure, which can more effectively and stably control and maintain the pressure value of the test oil; after the test oil pressure in the test container is maintained for a set time, it is detected whether the cavity above the elastic sealing component to be tested inside the test container is filled with test oil and pressure is formed, and a one-way overflow valve from the inside to the outside is provided above the test container to connect the inside and the outside of the test container. When the overflow valve overflows, it means that the sealing performance does not meet the requirements. If no overflow occurs, it means that the sealing performance meets the requirements.

After the test is completed, the test connecting pipe is pulled out upward to drive the test center pipe to move upward to complete the unsealing of the packer slips and the resetting of the elastic sealing assembly, and then the tested elastic sealing assembly is taken out to complete the test of this sealing performance.

Preferably, in order to further improve the accuracy of the test, a heating sleeve is provided on the outer wall of the test container, and the heating sleeve covers the area where the slip assembly and the elastic sealing assembly are located in the vertical direction. The heating sleeve can further simulate the sealing performance of the sealing mechanism in the high temperature environment underground, and can more accurately control the temperature value, truly simulate the actual working conditions, and thus improve the accuracy of the test.

Preferably, in order to more intuitively determine the sealing performance of the elastic sealing component, a test conduit connected to the inner cavity is provided above the test container, and the test conduit is connected to the cavity above the elastic sealing component in the test container. The inner cavity can be exhausted by connecting a one-way overflow valve from inside to outside to the test conduit, and at the same time, the overflow pressure of the overflow valve can be set to directly determine whether the sealing performance of the elastic sealing component meets the standard requirements. If overflow occurs after maintaining the pressure for a certain period of time, it can be directly determined as unqualified, and if no overflow occurs, it can be determined as qualified.

Preferably, in order to simulate the state of setting first and then sealing in the actual application process of the packer and the sealing mechanism, the packer control assembly includes a setting joint, an unsealing joint and a sliding push rod, the outer diameter of the test connection pipe is fixedly connected to the setting joint, the inner diameter of the test connection pipe is fixedly connected to the unsealing joint, the unsealing joint is detachably connected to the inner tube of the test center, and when the unsealing joint moves upward, it drives the sliding push rod to move upward at the same time;

The sliding push rod is slidably installed between the setting joint and the unsealing joint, and a through hole is provided on the pipe wall of the unsealing joint above the sliding push rod;

The bottom of the sliding push rod is in contact with the upper surface of the conical wedge; the bottom of the sliding push rod is provided with an inner flange extending inward, the top of the outer tube of the test center is provided with an outer flange extending outward, and the upper surface of the inner flange is in contact with the lower surface of the outer flange;

The bottom of the test center outer tube is fixedly connected to the upper end of the slip assembly, and the bottom of the slip assembly is fixedly connected to the outer diameter of the test center inner tube.

The present invention injects high-pressure oil into the test connection pipe by driving the oil connecting pipe. The high-pressure oil enters the cavity between the sealing joint and the unsealing joint through the through hole on the wall of the unsealing joint from the test connection pipe, and then pushes the sliding push rod to slide downward. First, the conical wedge is further squeezed toward the side of the metal elastic seal by force, and the outer edge of the metal elastic seal conical groove is stretched and fits with the inner wall of the test container to complete the sealing; then, as the oil pressure is further increased, the sliding push rod continues to slide downward, pushing the elastic sealing component to slide downward as a whole, and at the same time pushing the slips of the slip assembly to move toward the inner wall of the test container, so that the slip assembly is in close contact with the inner wall of the test container to complete the sealing fixation; the test oil connecting pipe injects the corresponding downhole pressure value into the test container, and at the same time starts the heating sleeve to heat the test container, so as to simulate the high temperature and high pressure conditions of the actual downhole to the greatest extent to test the sealing performance. After a period of heat preservation and pressure maintenance, the sealing performance is determined according to whether the cavity above the elastic sealing component in the test container is filled with oil.

After completing the sealing performance test, the packer needs to be unsealed and the elastic sealing assembly needs to be removed from the test container. First, the test oil pressure and the driving oil pressure are released at the same time, and then the unsealing joint is pulled upward through the test connecting pipe. The unsealing joint is separated from the inner tube of the test center. When the unsealing joint moves upward, the sliding push rod moves upward at the same time. The sliding push rod drives the outer tube of the test center upward alone. The outer tube of the test center moves relative to the inner tube of the test center to unseal the slip assembly, and the slip is separated from the inner wall of the test container. The test center tube is further pulled up to separate it from the test container and finally complete this sealing performance test.

Preferably, in order to ensure that the sealing mechanism maintains a continuous and stable sealing state during the test, a locking device is provided between the sliding push rod and the unsealing joint, and the locking device prevents the sliding push rod from moving upward. When the sliding push rod moves downward to the lowest point, the elastic sealing assembly achieves the best sealing state. Since the heat preservation and pressure test needs to be performed, it is necessary to ensure that the sliding push rod maintains the current relative position. The locking device can stably and reliably lock the relative position between the sliding push rod and the unsealing joint.

Preferably, in order to realize the control sequence of setting seal first and then sealing, a setting seal shear pin is provided between the sliding push rod and the outer tube of the test center.

The present invention drives the oil connecting pipe to inject high-pressure oil into the test connecting pipe, and the high-pressure oil enters the cavity between the sealing joint and the unsealing joint through the through hole on the pipe wall of the unsealing joint from the test connecting pipe, thereby pushing the sliding push rod to slide downward. Since a sealing shear pin is provided between the sliding push rod and the outer tube of the test center, the sliding push rod drives the outer tube of the test center to slide downward, thereby compressing the cava assembly to realize the movement of the cava toward the inner wall of the test container, so that the cava assembly is in close contact with the inner wall of the test container to complete the sealing fixation; then, as the oil pressure is further increased, the sliding push rod continues to slide downward, shears the sealing shear pin between the sliding push rod and the outer tube of the test center, and the sliding push rod separates from the outer tube of the test center and continues to move downward, pushing the conical wedge block to be further squeezed toward one side of the metal elastic seal by force, and the outer edge of the expanded conical groove of the metal elastic seal fits with the inner wall of the test container to complete the sealing.

Preferably, in order to achieve reliability of packer unsealing, an unsealing pin is provided between the unsealing joint and the inner tube of the test center.

Maintain the driving oil pressure, and at the same time, the test connecting pipe pulls the unsealing joint upwards. The unsealing joint and the inner tube of the test center move relative to each other to shear the unsealing pin; release the driving oil pressure, the unsealing joint continues to move upward, and then drives the sliding push rod to move upward at the same time, and the sliding push rod drives the outer tube of the test center to move upward. The outer tube of the test center and the inner tube of the test center move relative to each other to unseal the cava assembly, and the cava is separated from the inner wall of the test container. Further pulling separates the test center tube from the test container to finally complete this sealing performance test.

Preferably, in order to facilitate the installation of the test center tube and provide a stable and reliable unsealing force for the packer, an external push rod is installed on the top of the test bench assembly, and the external push rod is detachably connected to the top of the test connection tube. The external push rod can reliably and accurately push the test center tube to the specified position of the test container, and can provide sufficient pulling force to shear the unsealing pin when unsealing, thereby improving the test efficiency and saving time and effort.

Beneficial effects: The superelastic metal sealing mechanism of the present invention can achieve reliable sealing between the main oil pipe and the central oil pipe through the cooperation of the conical wedge block and the conical groove of the metal elastic seal, and the structure is simple, stable and reliable; and the high-temperature resistant superelastic metal seal replaces the conventional rubber cylinder seal, which improves the high-temperature and high-pressure resistance of the seal, and the superelastic metal seal is reusable, reducing the operation and maintenance cost of downhole tools in oil production.

The sealing performance testing device of the present invention can further simulate the sealing performance of the sealing mechanism under the high temperature and high pressure environment underground, and can more accurately control the temperature value, truly simulate the actual working conditions, thereby improving the accuracy of the test, and can intuitively determine the sealing performance of the elastic sealing component.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

FIG1 is a schematic diagram of the installation of the sealing mechanism of the present invention;

FIG2 is a schematic structural diagram of a sealing mechanism of the present invention;

FIG3 is a schematic diagram of the structure of the testing device of the present invention;

FIG4 is a cross-sectional view of a testing device of the present invention;

FIG5 is a cross-sectional view of the present invention during a sealing test;

FIG6 is a cross-sectional view of the initial state of the test of the present invention;

FIG7 is a cross-sectional view of the present invention in a setting state;

FIG8 is a cross-sectional view of the sealing state of the present invention;

FIG. 9 is a cross-sectional view of the present invention in an unsealed state.

Detailed ways

The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

In the description of the present invention, it is necessary to understand that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

As shown in Fig. 1 and Fig. 2, a super elastic metal sealing mechanism for a packer comprises a main oil pipe 101, a central oil pipe 102 and a slip assembly 103, wherein the central oil pipe 102 is located inside the main oil pipe 101, and the slip assembly 103 is installed at the outer diameter of the central oil pipe 102 and is located inside the main oil pipe 101; it is characterized in that: an elastic sealing assembly 104 is provided at the outer diameter of the central oil pipe 102, and the elastic sealing assembly 104 is located above the slip assembly 103; the elastic sealing assembly 104 comprises a conical wedge block 141 and a metal elastic seal 142 provided with a conical groove, the metal elastic seal 142 is sealed and fixedly connected to the outer wall of the central oil pipe 102, the conical wedge block 141 cooperates with the conical groove of the metal elastic seal 142, the conical wedge block 141 moves relative to the metal elastic seal 142 along the axial direction of the central oil pipe 102, and the outer diameter taper of the conical wedge block 141 is greater than the inner taper of the conical groove of the metal elastic seal 142;

When the conical wedge 141 is pressed toward one side of the metal elastic seal 142 by force, the conical groove of the metal elastic seal 142 is stretched open and its outer edge is in contact with the inner wall of the main oil pipe 101;

When the conical wedge block 141 no longer presses the metal elastic seal 142 , the conical groove of the metal elastic seal 142 is reset, and the outer edge thereof is separated from the inner wall of the main oil pipe 101 .

The present invention can achieve reliable sealing between the main oil pipe 101 and the central oil pipe 102 by cooperating between the conical wedge block 141 and the conical groove of the metal elastic seal 142, and the structure is simple, stable and reliable; and the high-temperature resistant superelastic metal seal replaces the conventional rubber cylinder seal, thereby improving the high-temperature and high-pressure resistance of the seal, and the superelastic metal seal is reusable, thereby reducing the operation and maintenance cost of downhole tools for oil production.

In order to further improve the sealing performance, the outer edge of the tapered groove of the metal elastic seal 142 is provided with a cylindrical elastic sealing portion 143. The cylindrical structure can increase the effective sealing area, and the elastic sealing portion 143 can form a more reliable seal with the inner wall of the rigid main oil pipe 101.

As shown in FIGS. 3, 4 and 5, in order to truly simulate the working conditions downhole and thus accurately detect the sealing performance of the sealing mechanism, a sealing performance testing device for a superelastic metal sealing mechanism for a packer is provided, comprising a test bench assembly 201, a test container 202, a test connecting pipe 203, a test center pipe 204, a slip assembly 103, an elastic sealing assembly 104 and a packer control assembly 205.

The test center pipe 204 includes a test center inner pipe 241 and a test center outer pipe 242. The test center inner pipe 241 is a tubular structure with a closed bottom. The top of the test center inner pipe 241 is connected to the test connecting pipe 203 through the packer control assembly 205 and is internally connected. The slip assembly 103 is installed on the outer wall of the lower end of the test center inner pipe 241. The test center outer pipe 242 is sleeved on the outer diameter of the test center inner pipe 241 and is connected to the slip assembly 103 in the axial direction. The metal elastic seal 142 is sealed and fixedly connected to the outer wall of the test center outer pipe 242.

A test oil connecting pipe 221 is provided at the bottom of the test container 202, and the test center pipe 204, together with the slip assembly 103, the elastic sealing assembly 104 and the packer control assembly 205, are installed inside the test container 202, and during the setting test, the slip assembly 103 and the elastic sealing assembly 104 are in contact with the inner wall of the test container 202 respectively;

The upper part of the test connection pipe 203 is provided with a driving oil connecting pipe 231 communicating with the inside. The test connection pipe 203 passes through the top of the test container 202 and is connected to the test center inner pipe 241 through the packer control assembly 205. The test connection pipe 203 is sealedly connected to the test container 202, and the driving oil connecting pipe 231 is located outside the test container 202.

The test container 202 is detachably mounted on the test bench assembly 201 along a vertical direction.

The sealing performance testing device of the present invention is characterized in that the elastic sealing component 104 and the slip component 103 to be tested are respectively installed on the test center pipe 204, and then the installed test center pipe 204 is sealedly installed inside the test container 202, and the slip component 103 is respectively controlled by the packer control component 205 to complete the simulation of the sealing and the sealing of the elastic sealing component 104, and finally, high-pressure oil is injected into the test container 202 from the test oil connecting pipe 221 at the bottom of the test container 202 to simulate the high-pressure state downhole; the bottom of the test center inner pipe 241 is a closed structure, which can more effectively and stably control and maintain the pressure value of the test oil; after the test oil pressure in the test container 202 is maintained for a set time, it is detected whether the cavity above the elastic sealing component 104 to be tested inside the test container 202 is filled with the test oil and pressure is formed, and a one-way overflow valve from inside to outside is provided above the test container 202 to connect the inside and outside of the test container 202, and when the overflow valve overflows, it means that the sealing performance does not meet the requirements, and if no overflow occurs, it means that the sealing performance meets the requirements.

After the test is completed, the test connecting pipe 203 is pulled out upward to drive the test center pipe 204 to move upward to complete the unsealing of the packer slips and the resetting of the elastic sealing assembly 104, and then the tested elastic sealing assembly 104 is taken out to complete the test of the sealing performance.

In order to further improve the accuracy of the test, a heating sleeve 206 is provided on the outer wall of the test container 202, and the heating sleeve 206 vertically covers the area where the slip assembly 103 and the elastic sealing assembly 104 are located. The heating sleeve 206 can further simulate the sealing performance of the sealing mechanism in the high temperature environment underground, and can more accurately control the temperature value, truly simulate the actual working conditions, and thus improve the accuracy of the test.

In order to more intuitively determine the sealing performance of the elastic sealing component 104, a test conduit 222 communicating with the inner cavity is provided above the test container 202, and the test conduit 222 communicates with the cavity above the elastic sealing component 104 in the test container 202. The inner cavity can be exhausted by connecting a one-way overflow valve from inside to outside to the test conduit 222, and at the same time, the sealing performance of the elastic sealing component 104 can be directly determined by setting the overflow pressure of the overflow valve. If overflow occurs after maintaining the pressure for a certain period of time, it can be directly determined as unqualified, and if no overflow occurs, it can be determined as qualified.

In order to facilitate the installation of the test center tube 204 and provide a stable and reliable unsealing force for the packer, an external push rod 207 is installed on the top of the test bench assembly 201, and the external push rod 207 is detachably connected to the top of the test connection tube 203. The external push rod 207 uses an electric push rod to reliably and accurately push the test center tube 204 to the specified position of the test container 202, and can provide sufficient pulling force to shear the unsealing pin 257 during unsealing, thereby improving the test efficiency and saving time and effort.

Example

As shown in FIGS. 6-9 , in order to simulate the state of setting first and then sealing in the actual application process of the packer and the sealing mechanism, the packer control assembly 205 includes a setting joint 251, an unsealing joint 252 and a sliding push rod 253. The outer diameter of the test connection pipe 203 is fixedly connected to the setting joint 251, the inner diameter of the test connection pipe 203 is fixedly connected to the unsealing joint 252, and the unsealing joint 252 is detachably connected to the test center inner tube 241. When the unsealing joint 252 moves upward, it drives the sliding push rod 253 to move upward at the same time.

The sliding push rod 253 is slidably installed between the setting joint 251 and the unsealing joint 252. The unsealing joint 252 is provided with a through hole 254 on the pipe wall above the sliding push rod 253.

The bottom of the sliding push rod 253 contacts the upper surface of the conical wedge 141; the bottom of the sliding push rod 253 is provided with an inner flange extending inward, and the top of the test center outer tube 242 is provided with an outer flange extending outward, and the upper surface of the inner flange contacts the lower surface of the outer flange;

The bottom of the test center outer tube 242 is fixedly connected to the upper end of the slip assembly 103 , and the bottom of the slip assembly 103 is fixedly connected to the outer diameter of the test center inner tube 241 .

The present invention injects high-pressure oil into the test connection pipe 203 by driving the oil connecting pipe 231. The high-pressure oil enters the cavity between the setting joint 251 and the unsealing joint 252 through the through hole 254 on the wall of the unsealing joint 252 from the test connection pipe 203, and then pushes the sliding push rod 253 to slide downward. First, the conical wedge block 141 is further squeezed toward the side of the metal elastic seal 142 by force, and the outer edge of the expanded conical groove of the metal elastic seal 142 is fitted with the inner wall of the test container 202 to complete the sealing; then, with the oil pressure, the sealing of the test container 202 is completed. The sliding push rod 253 is further raised to continue to slide downward, pushing the elastic sealing assembly 104 to slide downward as a whole, and at the same time pushing the slips of the slip assembly 103 to move toward the inner wall of the test container 202, so that the slip assembly 103 is in close contact with the inner wall of the test container 202 to complete the setting and fixing; the test oil connecting pipe 221 injects the corresponding downhole pressure value into the test container 202, and at the same time starts the heating sleeve 206 to heat the test container 202, which can simulate the actual high temperature and high pressure conditions in the well to the greatest extent to test the sealing performance. After a period of heat preservation and pressure maintenance, the sealing performance is determined based on whether the cavity above the elastic sealing assembly 104 in the test container 202 is filled with oil.

After the sealing performance test is completed, the packer needs to be unsealed and the elastic sealing assembly 104 is removed from the test container 202. First, the test oil pressure and the driving oil pressure are released at the same time, and then the unsealing joint 252 is pulled upward through the test connecting pipe 203, and the unsealing joint 252 is separated from the test center inner tube 241. When the unsealing joint 252 moves upward, it drives the sliding push rod 253 to move upward at the same time. The sliding push rod 253 drives the test center outer tube 242 upward alone, and the test center outer tube 242 and the test center inner tube 241 move relative to each other to realize the unsealing of the slip assembly 103, and the slip is separated from the inner wall of the test container 202. The test center tube 204 is further pulled up to separate it from the test container 202 and finally complete this sealing performance test.

In order to ensure that the sealing mechanism maintains a continuous and stable sealing state during the test, a through hole 255 is provided between the sliding push rod 253 and the unsealing joint 252, and the through hole 255 prevents the sliding push rod 253 from moving upward. When the sliding push rod 253 moves downward to the lowest point, the elastic sealing assembly 104 achieves the best sealing state. Since the heat preservation and pressure test needs to be performed, it is necessary to ensure that the sliding push rod 253 maintains the current relative position. The through hole 255 can stably and reliably lock the relative position between the sliding push rod 253 and the unsealing joint 252.

Example

As shown in FIGS. 6-9 , in order to realize the control sequence of setting first and then sealing, a setting shear pin 256 is provided between the sliding push rod 253 and the test center outer tube 242 .

The present invention injects high-pressure oil into the test connection pipe 203 by driving the oil connecting pipe 231. The high-pressure oil enters the cavity between the sealing joint 251 and the unsealing joint 252 through the through hole 254 on the pipe wall of the unsealing joint 252 from the test connection pipe 203, thereby pushing the sliding push rod 253 to slide downward. Since a sealing shear pin 256 is provided between the sliding push rod 253 and the test center outer pipe 242, the sliding push rod 253 drives the test center outer pipe 242 to slide downward, thereby compressing the slip assembly 103 to realize the slip movement toward the inner wall of the test container 202. , so that the slip assembly 103 is in close contact with the inner wall of the test container 202 to complete the sealing and fixing; then as the oil pressure is further increased, the sliding push rod 253 continues to slide downward, shearing the sealing shear pins 256 between the sliding push rod 253 and the test center outer tube 242, and the sliding push rod 253 is separated from the test center outer tube 242 and continues to move downward, pushing the conical wedge block 141 to be further squeezed toward the side of the metal elastic seal 142, and the outer edge of the conical groove of the metal elastic seal 142 is stretched open and fits with the inner wall of the test container 202 to complete the sealing.

Example

As shown in FIGS. 6-9 , in order to achieve reliability of packer unsealing, an unsealing pin 257 is provided between the unsealing joint 252 and the test center inner tube 241 .

Maintain the driving oil pressure, and at the same time, the test connecting pipe 203 pulls the unsealing joint 252 upwards, and the unsealing joint 252 and the test center inner tube 241 move relative to each other to cut the unsealing pin 257; release the driving oil pressure, the unsealing joint 252 continues to move upward, thereby driving the sliding push rod 253 to move upward at the same time, and the sliding push rod 253 drives the test center outer tube 242 to move upward, and the test center outer tube 242 and the test center inner tube 241 move relative to each other to realize the unsealing of the cava assembly 103, and the cava is separated from the inner wall of the test container 202, and further pulled up to separate the test center tube 204 from the test container 202 to finally complete this sealing performance test.

In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A superelastic metal sealing mechanism for a packer, comprising a main oil pipe (101), a central oil pipe (102) and a slip assembly (103), wherein the central oil pipe (102) is located inside the main oil pipe (101), and the slip assembly (103) is installed on the central oil pipe (102) and the outer diameter thereof is located inside the main oil pipe (101); the characteristics are as follows: an elastic sealing assembly (104) is provided on the outer diameter of the central oil pipe (102), and the elastic sealing assembly (104) is located above the slip assembly (103); the elastic sealing assembly (104) is provided on the outer diameter of the central oil pipe (102), and the elastic sealing assembly (104) is located above the slip assembly (103); the elastic sealing assembly (104) is provided on the outer diameter of the central oil pipe (102), and the elastic sealing assembly (104) is provided on the outer diameter thereof. The assembly (104) comprises a tapered wedge (141) and a metal elastic seal (142) provided with a tapered groove, wherein the metal elastic seal (142) is sealed and fixedly connected to the outer wall of the central oil pipe (102), the tapered wedge (141) cooperates with the tapered groove of the metal elastic seal (142), the tapered wedge (141) moves relative to the metal elastic seal (142) along the axial direction of the central oil pipe (102), and the outer diameter taper of the tapered wedge (141) is greater than the inner taper of the tapered groove of the metal elastic seal (142); When the conical wedge (141) is pressed toward one side of the metal elastic seal (142) by force, the conical groove of the metal elastic seal (142) is stretched open and its outer edge is in contact with the inner wall of the main oil pipe (101); When the conical wedge (141) no longer presses the metal elastic seal (142), the conical groove of the metal elastic seal (142) is reset, and the outer edge thereof is separated from the inner wall of the main oil pipe (101). 2. The superelastic metal sealing mechanism for a packer according to claim 1, characterized in that a cylindrical elastic sealing portion (143) is provided on the outer edge of the conical groove of the metal elastic sealing member (142). 3. The sealing performance testing device of the super elastic metal sealing mechanism for a packer according to claim 1, characterized in that it comprises a test bench assembly (201), a test container (202), a test connecting pipe (203), a test center pipe (204), a slip assembly (103), an elastic sealing assembly (104) and a packer control assembly (205), The test center pipe (204) comprises a test center inner pipe (241) and a test center outer pipe (242); the test center inner pipe (241) is a tubular structure with a closed bottom; the top of the test center inner pipe (241) is connected to the test connecting pipe (203) through a packer control assembly (205) and is internally connected; the slip assembly (103) is installed on the outer wall of the lower end of the test center inner pipe (241); the test center outer pipe (242) is sleeved on the outer diameter of the test center inner pipe (241) and is connected to the slip assembly (103) in the axial direction; the metal elastic seal (142) is sealed and fixedly connected to the outer wall of the test center outer pipe (242); A test oil connecting pipe (221) is provided at the bottom of the test container (202); the test center pipe (204) together with the slip assembly (103), the elastic sealing assembly (104) and the packer control assembly (205) are installed inside the test container (202); and during the setting test, the slip assembly (103) and the elastic sealing assembly (104) are respectively in contact with the inner wall of the test container (202); A driving oil connecting pipe (231) communicating with the interior is provided at the upper portion of the test connecting pipe (203); the test connecting pipe (203) penetrates the top of the test container (202) and communicates with the test center inner pipe (241) via the packer control assembly (205); the test connecting pipe (203) and the test container (202) are sealed and connected; the driving oil connecting pipe (231) is located outside the test container (202); The test container (202) is detachably mounted on the test bench assembly (201) in a vertical direction. 4. The sealing performance testing device of the superelastic metal sealing mechanism for the packer according to claim 3 is characterized in that: a heating sleeve (206) is provided on the outer wall of the test container (202), and the heating sleeve (206) covers the area where the slip assembly (103) and the elastic sealing assembly (104) are located in the vertical direction. 5. The sealing performance testing device of the superelastic metal sealing mechanism for a packer according to claim 3 or 4, characterized in that a test conduit (222) connected to the inner cavity is provided above the test container (202), and the test conduit (222) is connected to the cavity above the elastic sealing assembly (104) in the test container (202). 6. The sealing performance testing device of the superelastic metal sealing mechanism for the packer according to claim 3, characterized in that: the packer control assembly (205) comprises a sealing joint (251), an unsealing joint (252) and a sliding push rod (253); the outer diameter of the test connection pipe (203) is fixedly connected to the sealing joint (251); the inner diameter of the test connection pipe (203) is fixedly connected to the unsealing joint (252); the unsealing joint (252) is detachably connected to the test center inner tube (241); when the unsealing joint (252) moves upward, it drives the sliding push rod (253) to move upward at the same time; The sliding push rod (253) is slidably installed between the setting joint (251) and the unsealing joint (252); a through hole (254) is provided on the pipe wall of the unsealing joint (252) above the sliding push rod (253); The bottom of the sliding push rod (253) contacts the upper surface of the conical wedge (141); the bottom of the sliding push rod (253) is provided with an inner flange extending inwardly, the top of the test center outer tube (242) is provided with an outer flange extending outwardly, and the upper surface of the inner flange contacts the lower surface of the outer flange; The bottom of the test center outer tube (242) is fixedly connected to the upper end of the slip assembly (103), and the bottom of the slip assembly (103) is fixedly connected to the outer diameter of the test center inner tube (241). 7. The sealing performance testing device of the superelastic metal sealing mechanism for the packer according to claim 6 is characterized in that a locking device (255) is provided between the sliding push rod (253) and the unsealing joint (252), and the locking device (255) prevents the sliding push rod (253) from moving upward. 8. The sealing performance testing device of the superelastic metal sealing mechanism for a packer according to claim 6 or 7, characterized in that a sealing shear pin (256) is provided between the sliding push rod (253) and the test center outer tube (242). 9. The sealing performance testing device of the superelastic metal sealing mechanism for a packer according to claim 6 or 7, characterized in that an unsealing pin (257) is provided between the unsealing joint (252) and the test center inner tube (241). 10. The sealing performance testing device of the superelastic metal sealing mechanism for a packer according to claim 9, characterized in that an external push rod (207) is installed above the test bench assembly (201), and the external push rod (207) is detachably connected to the top of the test connecting pipe (203).