CN104153735A - Expansion tube subsidy device - Google Patents

Abstract

The invention discloses an expansion tube subsidizing device, comprising: an expansion tube, an upper expansion cone, a lower expansion cone, and a force applying component. The expansion tube is a hollow column extending along the axis, and the column has a first port and a second port opposite to each other. The upper expansion cone and the lower expansion cone are provided with conical surfaces, and the respective conical surfaces of the upper expansion cone and the lower expansion cone are respectively clamped on the first port and the second port of the expansion tube. The force applying component can drive the upper expansion cone and the lower expansion cone to move toward each other along the axial direction of the expansion tube. The expansion pipe subsidy device of the present invention can efficiently realize primary and secondary repairs for casing damaged wells.

Description

Expansion tube subsidy device

technical field

The invention relates to a downhole mechanical tool for oil development, in particular to an expansion pipe subsidy device.

Background technique

In the field of petroleum development, with the prolongation of oilfield development time, wells with casing damage (abbreviated as casing damage) are increasing year by year. In the prior art, an expansion pipe subsidy device is usually used to subsidize the casing damage wells. Wherein, the expansion pipe is a metal steel pipe made of special material with good plasticity, which can be expanded to a predetermined inner diameter and outer diameter in the diameter direction by mechanical or hydraulic means after being lowered into the well. When the expansion tube is used to subsidize the casing, the expansion tube with a smaller diameter is first lowered into the casing damaged well, and the overall plastic expansion of the expansion tube occurs under the action of mechanical force or hydraulic pressure, and it clings to the inner wall of the casing of the wellbore. So as to achieve anchoring and sealing.

As shown in Fig. 1, the existing expansion pipe subsidy device includes: expansion pipe 1a, expansion cone 2a, bottom plug 3a, oil pipe 4a and sealing device 5a. The sealing device 5a is usually rubber, fixed on the outer wall of the expansion tube 1a, and can be used to seal the annular space between the expansion tube 1a and the casing b after the expansion tube 1a is expanded. The bottom plug 3a is fixed on the lower end of the expansion tube 1a, and is used to seal the lower end surface of the expansion tube 1a, so as to ensure that the cavity surrounded by the expansion tube 1a and the expansion cone 2a can form a high-pressure chamber B during the expansion process. . The lower end of the oil pipe 4a is fixedly connected to the upper end of the expansion cone 2a, and the expansion pipe 1a hangs on the slope of the expansion cone 2a, so that the string weight of the entire expansion pipe 1a is suspended by the oil pipe 4a. When in use, this set of devices can first use the oil pipe 4a to lower the expansion cone 2a connected to it and the expansion tube 1a suspended on the expansion cone 2a to the predetermined position where the casing b is damaged; When subsidizing the position of the casing b, use a high-pressure pump on the ground to inject liquid into the oil pipe 4a; since the bottom end of the expansion pipe is provided with a bottom plug 3a, a high-pressure chamber B is formed between the expansion pipe 1a, the bottom plug 3a and the expansion cone 2a; When the pressure in the high-pressure chamber B reaches a certain value, the expansion cone 2a moves upward together with the oil pipe 4a under the push of the liquid pressure until it walks out of the expansion pipe 1a to complete the expansion process.

As shown in Fig. 2, when the expansion pipe 1a is expanded, it is necessary to pull out the oil pipe 4a, and then lower the milling tool to drill the bottom plug 3a at the lower end of the expansion pipe 1a. However, the above-mentioned milling and milling of the bottom plug 3a is cumbersome and time-consuming, which leads to low efficiency in the entire process of subsidizing the expansion tube.

Therefore, there is a need for an efficient expansion pipe subsidy device at present.

Contents of the invention

The purpose of the present invention is to provide an expansion pipe subsidy device, which can efficiently repair casing damaged wells.

In order to achieve the above object, the technical solution provided by the present invention is as follows:

An expansion pipe subsidy device, comprising: an expansion pipe, an upper expansion cone, a lower expansion cone, and a force application assembly, the expansion pipe is a hollow pipe string extending along the axis, and the pipe string has opposite first ports and the second port; the upper expansion cone and the lower expansion cone are provided with conical surfaces, and the respective conical surfaces of the upper expansion cone and the lower expansion cone are respectively stuck on the first port and the second port of the expansion tube; the The force applying component can drive the upper expansion cone and the lower expansion cone to move toward each other along the axial direction of the expansion tube.

In a preferred embodiment, the expansion tube is arranged in the subsidized casing, and in a direction perpendicular to the axis of the expansion tube, the thickness of both sides of the expansion tube is the same as that of the upper expansion cone and the lower expansion cone. The sum of the maximum outer diameters is greater than the inner diameter of the subsidized casing, and the maximum outer diameters of the upper expansion cone and the lower expansion cone are smaller than the inner diameter of the subsidized casing.

In a preferred embodiment, the expanded outer diameter of the expansion tube is 0.1 mm to 0.8 mm larger than the inner diameter of the subsidized sleeve.

In a preferred embodiment, the maximum outer diameter of the upper expansion cone and the lower expansion cone is not smaller than the outer diameter of the expansion tube.

In a preferred embodiment, the force applying component is arranged in the hollow part of the expansion tube, which includes: a piston tube, a piston disc, a hydraulic cylinder,

The piston tube is a hollow tube column, one end of which is located in the liquid cylinder and fixedly connected with the piston disk, and the other end protrudes out of the liquid cylinder and is fixedly connected with the upper expansion cone. There is also a flow hole communicating with the hydraulic cylinder;

The piston disc is arranged in the liquid cylinder, and its diameter is the same as the inner diameter of the liquid cylinder;

The liquid cylinder is arranged in the expansion tube, and a piston hole is opened on the upper surface of the liquid cylinder, and the piston tube passes through the piston hole.

In a preferred embodiment, the center of the upper expansion cone is provided with a through first hole, and the piston tube in the force application assembly passes through the first hole and is connected to the upper expansion cone.

In a preferred embodiment, a lower connecting rod is further provided at the lower end of the liquid cylinder, one end of the lower connecting rod is connected to the liquid cylinder, and the other end is connected to the lower expansion cone.

In a preferred embodiment, an anchor is provided between the piston tube and the expansion tube annulus.

In a preferred embodiment, the expansion tube includes a body section and a thin-walled section extending outward from the body section, the thin-walled section is in contact with the upper expansion cone, and the wall thickness of the thin-walled section is smaller than that of the expansion tube body segment wall thickness.

In a preferred embodiment, the maximum outer diameter of the upper expansion cone is smaller than the maximum outer diameter of the lower expansion cone.

Beneficial effects: Compared with the existing expansion tube subsidy device, the expansion tube subsidy device of the present invention can sit directly on the conical surfaces of the upper expansion cone and the lower expansion cone, and through the above structure The improvement realizes that the upper expansion cone and the lower expansion cone are placed outside the expansion tube, and the bottom plug in the prior art is cancelled. When the upper and lower expansion cones are used to expand the expansion tube, there is no need to lower the milling tool again, so The efficiency of the expansion pipe subsidy device is greatly improved. In addition, while canceling the bottom plug, the high-pressure chamber is also correspondingly cancelled. The wall of the high-pressure chamber in the prior art is thin and the internal pressure is high, so the strength is relatively poor, and leakage is prone to occur during the expansion process, which will reduce the success rate of expansion. When the high-pressure cavity structure is canceled, the expansion success rate of the expansion tube is further improved. In addition, the high-pressure chamber in the prior art is the place where the outer diameter of the entire expansion tube subsidy device is the largest. After canceling, it is beneficial to reduce the maximum outer diameter of the entire set of devices, thereby improving the passability of the expansion tube subsidy device, and it is easy to pass through once. The subsidy position of the subsidized bushing, so that the subsidy can be realized for the positions below the subsidy position of the subsidized bushing after one subsidy.

The present invention not only effectively solves the problem that it is difficult to subsidize the leakage point below the subsidized position of the casing after one subsidy, but further, the present invention sets a thin-walled section on the upper end of the expansion tube or sets the maximum outer diameter of the upper expansion cone to a lower The maximum outer diameter of the expansion cone is slightly smaller, so that the position of the expansion tube for the second subsidy can be precisely positioned, and the expansion tube for the second subsidy can be seamlessly connected with the expansion tube for the first subsidy, which is good for field application.

Description of drawings

Fig. 1 is a structural schematic diagram of an expansion pipe subsidy tool in the prior art;

Fig. 2 is a schematic diagram of the structure of a casing damaged well repaired by an expansion pipe subsidy tool in the prior art;

Fig. 3 is a schematic structural view of an expansion tube subsidy device in the first embodiment of the present invention;

Fig. 4 is a schematic structural view of an expansion tube of an expansion tube subsidizing device in the first embodiment of the present invention;

Fig. 5 is a structural schematic diagram of an expansion cone on an expansion tube subsidizing device in the first embodiment of the present invention;

Fig. 6 is a structural schematic diagram of an expansion cone under an expansion tube subsidizing device in the first embodiment of the present invention;

Fig. 7 is a schematic structural view of an expansion tube subsidizing device in the second embodiment of the present invention;

Fig. 8 is an expansion working state diagram of an expansion tube subsidizing device in the second embodiment of the present invention;

Fig. 9 is a schematic structural view of a casing damaged well subsidized by an expansion tube subsidizing device in the second embodiment of the present invention.

Detailed ways

The technical scheme of the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. After reading the present invention, those skilled in the art Modifications to various equivalent forms of the present invention fall within the scope defined by the appended claims of the present application.

The invention provides an expansion pipe subsidy device, which is used for efficiently repairing casing damaged wells.

The upper or lower position described in this article refers to the use state of the expansion tube subsidy device after entering the downhole. To be precise, the position of the upper expansion cone of the expansion tube subsidy device is relatively up and down. The position of the cone is relatively downward.

Please refer to FIG. 3 , the expansion tube subsidizing device proposed in the first embodiment of the present invention includes: an expansion tube 1 , an upper expansion cone 2 , a lower expansion cone 3 , and a force applying component 4 .

The expansion pipe 1 is a metal steel pipe made of special material and has good plasticity. After being lowered into the well, it can be expanded to a predetermined inner diameter and outer diameter along the diameter direction by mechanical or hydraulic means. The specific material of the metal may be stainless steel with strong corrosion resistance.

Please refer to FIG. 4 , in an embodiment of the present invention, the expansion tube 1 is a hollow column extending along the axis O, and the column has a first port 12 and a second port 13 opposite to each other. In a natural state before expansion, the expansion tube 1 has an outer diameter smaller than an inner diameter of the casing b to be repaired. After the expansion tube 1 is expanded, it directly fits and seals with the casing to be repaired. The length of the expansion tube 1 is determined according to the damage of the sleeve, and it is necessary to ensure that the expansion tube 1 can completely fit and seal with the damaged position of the sleeve b after expansion. An upper expansion cone 2 is provided on the first port 12 of the expansion tube 1 . On the second port 13 of the expansion tube 1, a lower expansion cone 3 is arranged. A force application assembly 4 may be provided in the hollow part of the expansion tube 1, and the force application assembly 4 can drive the upper expansion cone 2 and the lower expansion cone 3 to move toward each other along the axial direction.

The upper expansion cone 2 is stuck on the first port 12 of the expansion tube 1 for expanding the upper part of the expansion tube 1 .

Referring to FIG. 5 for details, the upper expansion cone 2 includes a cone 20 and a cylinder 21 extending outward based on the large end surface of the cone 20 . The outer diameter of the cylinder 21 is the same as the largest outer diameter of the cone 20 . The smallest outer diameter at the small end surface of the cone 20 is smaller than the inner diameter of the expansion tube 1 . The maximum outer diameter of the cone 20 is larger than the inner diameter of the expansion tube 1 to ensure that the cone 20 of the upper expansion cone 2 can partially snap into the hollow column at the upper end of the expansion tube 1 . When the upper expansion cone 2 moves downward relative to the expansion tube 1, the expansion tube 1 can be expanded.

In one embodiment, the maximum outer diameter of the upper expansion cone 2 is not smaller than the outer diameter of the expansion tube 1 . When the maximum outer diameter of the upper expansion cone 2 is larger than the outer diameter of the expansion tube 1 , a sealing device may be provided on the outer wall of the expansion tube 1 . The sealing device may be vulcanized rubber. When the outer diameter of the expansion tube 1 is the same as the maximum outer diameter of the upper expansion cone 2, when the expansion tube subsidy device according to the present invention is lowered into the casing b to be repaired, the outer diameters are the same The device can be relatively easy to ensure the passability.

The center of the upper expansion cone 2 is provided with a first hole 22 . The first hole 22 is a through hole. The first hole 22 is used for connecting with the force applying component 4 . For example, threads are provided on the hole wall of the first through hole 22 for mating connection with the force applying component 4 .

The lower expansion cone 3 is stuck in the lower part of the expansion tube 1. When the lower expansion cone 3 passes through the hollow part of the expansion tube 1, the entire expansion tube 1 can be fully expanded, especially if it is not expanded by the upper expansion tube. Cone 2 inflated expanded tube 1 part.

Please refer to FIG. 7 , the structural shape of the lower expansion cone 3 may be consistent with that of the upper expansion cone 2 . The lower expansion cone 3 includes a cone 30 and a cylinder 31 extending outward based on the large end surface of the cone 30 . The outer diameter of the cylinder 31 is the same as the largest outer diameter of the cone 30 . The minimum outer diameter at the small end surface of the cone 30 is smaller than the inner diameter of the expansion tube 1, and the maximum outer diameter of the cone 30 is greater than the inner diameter of the expansion tube 1, so as to ensure the conical shape of the upper expansion cone 2. The body 30 can be partially snapped into the hollow pipe column at the lower end of the expansion pipe 1 . When the lower expansion cone 3 moves upward relative to the expansion tube 1, the expansion tube 1 can be fully expanded.

In one embodiment, the maximum outer diameter of the lower expansion cone 3 is not smaller than the outer diameter of the expansion tube 1 . When the maximum outer diameter of the lower expansion cone 3 is larger than the outer diameter of the expansion tube 1 , a sealing device may be provided on the outer wall of the expansion tube 1 . The sealing device may be vulcanized rubber. When the outer diameter of the expansion tube 1 is the same as the maximum outer diameter of the lower expansion cone 3, when the expansion tube subsidizing device of the present invention is inserted into the casing b to be repaired, the outer diameters are the same The device can be relatively easy to ensure the passability.

In a specific embodiment, when it is necessary to subsidize the 5 ^1/2 casing, an expansion tube with an outer diameter of 114 mm _and a thickness of 5 mm can be selected, and an expansion cone with a maximum outer diameter of 115 mm can be selected. When the expansion After the tube is expanded, its expansion rate is 8.6%, and the interference of the expanded tube relative to the inner diameter of the sleeve is 0.5 mm. The 5 ^1/2 sleeve specifically refers to the dimensions: an outer diameter of 139.7 mm, a thickness of 7.72 mm, and an _inner diameter of 124.3 mm.

The forcing assembly 4 is fixedly connected to the upper expansion cone 2 and the lower expansion cone 3 respectively. Through the movement of the force applying assembly 4, the upper expansion cone 2 and the lower expansion cone 3 are driven to move relative to each other along the axial direction O of the expansion tube 1, so that the upper expansion cone 2 and the lower expansion cone 3 can be The expansion of the expansion tube 1 is achieved during the movement relative to the expansion tube 1 .

In the embodiment of the present invention, the force application assembly 4 is used to apply force to the upper expansion cone 2 and the lower expansion cone 3 to realize the expansion of the expansion tube 1 . The force applied by the force applying component 4 may be mechanical or hydraulic. When it is hydraulic, the force applying component 4 may be a hydraulic component. The hydraulic assembly includes: a piston tube 41 , a piston disc 42 , a hydraulic cylinder 43 , and a lower connecting rod 44 . The hydraulic assembly is arranged in the hollow part of the expansion tube 1 .

The piston tube 41 is a hollow tube column, one end of which is set in the liquid cylinder 43 and is fixedly connected with the piston plate 42 , and the other end extends out of the liquid cylinder 43 . The pipe section of the piston pipe 41 protruding from the liquid cylinder 43 can pass through the upper expansion cone 2 and be fixedly connected with the upper expansion cone 2 . In use, one end of the piston tube 41 passing through the upper expansion cone 2 can be fixedly connected with the running string. The running string may be an oil pipe. The way of the fixed connection can be threaded connection, that is, an external thread can be provided on the outer surface of the piston tube 41 to match the internal thread of the first hole 22 of the upper expansion cone 2 . A flow hole 410 is also opened on the piston tube 41 . The flow hole 410 communicates with the liquid cylinder 43 . The high-pressure liquid flows into the cylinder 43 from the flow hole 410 through the hollow part of the piston tube 41. When the pressure in the cylinder 43 reaches a certain level, the cylinder 43 can move upward under the action of hydraulic pressure.

The piston plate 42 is arranged in the hydraulic cylinder 43 . The piston disc 42 as a whole can be a disc structure. The diameter of the piston disc 42 is the same as the inner diameter of the hydraulic cylinder 43 . The upper end surface of the piston disc 42 is fixedly connected with the piston tube 41 . When the outside world injects high-pressure liquid into the piston tube 41 , the high-pressure liquid flows out from the flow hole 410 and acts on the piston plate 42 , thereby causing the piston plate 42 to move downward. During the downward movement of the piston disc 42 , it drives the piston tube 41 fixedly connected thereto and the upper expansion cone 2 fixedly connected with the piston tube 41 to move downward together.

The hydraulic cylinder 43 is arranged in the expansion tube 1 . The whole of the hydraulic cylinder 43 can be a hollow shell, and the hollow part can be a closed cylindrical cavity. A piston hole 430 is defined on the upper surface of the liquid cylinder 43 , and one end of the piston tube 41 passes through the piston hole 430 . A sealing device is provided at the joint between the piston tube 41 and the piston hole 430 to ensure the sealing of the hydraulic components.

The upper end of the lower connecting rod 44 is fixedly connected with the lower end surface of the hydraulic cylinder 43 . The fixed connection method may be welding or other fixed connection methods. The lower end of the lower connecting rod 44 is fixedly connected with the lower expansion cone 3 . The manner of the fixed connection may be threaded connection. Specifically, an external thread is provided at the lower end of the lower connecting rod 44 ; correspondingly, a second hole 32 may be provided at the middle of the lower expansion cone 3 . The hole wall of the second hole 32 is provided with an internal thread, which is matched with the external thread of the lower connecting rod 44 .

When the expansion tube subsidy device of the present invention is in use, the piston tube 41 is first connected with the oil pipe to ensure that the piston tube 41 is communicated with the oil tube; then the expansion tube subsidy device is lowered into the Predetermined position at the damaged part of the casing; then inject high-pressure liquid into the oil pipe. The high-pressure liquid first flows into the piston tube 41 along the oil tube, then flows out from the flow hole of the piston tube 41 , and enters the enclosed space formed by the piston plate 42 and the hydraulic cylinder 43 . When the high-pressure liquid fills the enclosed space formed by the piston plate 42 and the hydraulic cylinder 43 and reaches a certain pressure, the hydraulic cylinder 43 moves upward. During the upward movement, the liquid cylinder 43 drives the lower expansion cone 3 to move upward relative to the upper expansion cone 2. After the lower expansion cone 3 moves upward for a certain distance, the lower part of the expansion tube 1 is completely closed. Inflated, it fits completely with the sleeve b, so that the expansion tube 1 is anchored on the sleeve b, and at this time, the expansion tube 1 is positioned. Then the force applying assembly 4 is moved upwards, thereby driving the lower expansion cone 3 to move upwards. When the lower expansion cone 3 is removed from the expansion tube 1, the lower expansion cone 3 has completed the expansion of the expansion tube 1, and the expanded expansion tube 1 is completely attached to the casing to be repaired. close, so that the expansion tube 1 also realizes the repair of the casing to be repaired. When the strength of the expansion tube 3 is not completely uniform, for example, when the strength of the upper expansion cone 2 is weaker than that of the lower expansion cone 3, during the upward movement of the above-mentioned hydraulic cylinder 43, the upper The expansion cone 2 can be expanded first under the action of the hydraulic cylinder 43 . When the upper expansion cone 2 is expanded first, the upper expansion cone 2 is anchored with the sleeve b, and at this time, the entire force application component 4 is lifted up, and the entire expansion is realized through the lower expansion cone 3 Complete expansion of the full pipe section of pipe 1. When the expansion tube 1 is fully expanded, it is positioned with the sleeve b through an interference fit. Specifically, the expanded outer diameter of the expansion tube 1 may be 0.1 mm to 0.8 mm larger than the inner diameter of the subsidized sleeve b, that is, the interference is 0.1 mm to 0.8 mm.

When the method of applying force by the force applying component 4 in the present invention is mechanical, the force applying component 4 may be a drawing machine in the prior art. The drawing machine is provided with a fixing device and a piston rod, the fixing device can fix the expansion tube 1 , and the piston rod is fixedly connected with the upper expansion cone 2 and the lower expansion cone 3 . The up and down movement of the piston rod can successively drive the movement of the upper expansion cone 2 and the lower expansion cone 3 fixedly connected therewith, thereby realizing the expansion of the expansion tube 1 .

In the expansion tube subsidy device according to the present invention, the expansion tube 1 can directly sit on the conical surfaces of the upper expansion cone 2 and the lower expansion cone 3, and the upper expansion cone 2 and the lower expansion cone 3 are externally placed through the above structural improvement For the expansion tube 1, the bottom plug 3a in the prior art is eliminated. When the expansion tube is expanded by the upper and lower expansion cones during use, there is no need to lower the milling tool again, thus greatly improving the efficiency of the expansion tube subsidy device . The expansion pipe subsidizing device of the present invention cancels the high-pressure chamber B correspondingly while canceling the bottom plug. The wall of the high-pressure chamber B in the prior art is thin and the internal pressure is high, so the strength is relatively poor, and leakage is prone to occur during the expansion process, which will reduce the success rate of expansion. After canceling the high-pressure chamber structure, the expansion success rate of the expansion tube 1 is further improved.

After using the existing expansion tube subsidy device to subsidize the casing, the inner diameter of the subsidized section of the casing will be smaller than that of the non-subsidized section. If the part below the casing is damaged, use the existing expansion tube subsidy device for a second time. When subsidizing, because the outer diameter of the high-pressure chamber B part containing the expansion cone 2a is relatively large, it is difficult to pass through the original primary subsidizing well section. If the outer diameter of the whole set of expansion tube subsidizing device is reduced in order to pass through the subsidized well section once, it is likely to exceed the expandable range of the expansion tube 1a, and the expansion tube 1a is difficult to subsidize in place.

Since the high-pressure chamber in the prior art is the place with the largest outer diameter of the expansion tube subsidy device, after the present invention cancels it, it is beneficial to reduce the maximum outer diameter of the whole set of devices, thereby improving the passability of the expansion tube subsidy device. It is easy to pass through the subsidized part of the bushing after one subsidy, so that the subsidy can be realized for the position below the subsidized part of the subsidized bushing after one subsidy.

When the position to be repaired by the secondary subsidy is relatively close to the position of the primary subsidy, generally, the position of the upper end of the expansion tube 1 is difficult to locate accurately. Usually, when the expansion tube subsidy device is used for subsidy, the expansion tube of the secondary subsidy is easy to overlap with the expansion tube of the primary subsidy, and it is difficult for the expansion tube 1 of the secondary subsidy to be seamlessly connected with the expansion tube of the primary subsidy. In view of the above problems, the present invention further proposes a second embodiment.

Please refer to Fig. 6, in the second embodiment of the present invention, the proposed expansion tube subsidy device also includes: expansion tube 1, upper expansion cone 2, lower expansion cone 3, force application assembly 4, that is, the expansion tube in the second embodiment The composition and connection relationship of the pipe subsidy device can be consistent with that in the first embodiment. The difference is that the expansion tube 1 includes a body section 10 and a thin-wall section 11 . The thin-walled section 11 is a pipe section extending upward from the body section 10 of the expansion tube 1 . The wall thickness of the thin-walled section 11 is smaller than the wall thickness of the main body section 10 of the expansion tube 1 . For example, the wall thickness of the thin-walled section 11 may be half of the wall thickness of the body section 10, and the length of the thin-walled section 11 may be 100 mm.

Please refer to FIG. 8 , when the expansion tube subsidizing device is in use, first connect the piston tube 41 to the oil pipe to ensure that the piston tube 41 communicates with the oil pipe. Then use the oil pipe to preliminarily lower the expansion pipe subsidy device to a predetermined position at the damaged part of the casing; then inject high-pressure liquid into the oil pipe. The high-pressure liquid first flows into the piston tube 1 along the oil tube, then flows out from the flow hole 410 of the piston tube 41 , and enters the enclosed space formed by the piston disc 42 and the hydraulic cylinder 43 . When the high-pressure liquid fills the enclosed space formed by the piston plate 42 and the hydraulic cylinder 43 and reaches a certain pressure, the hydraulic cylinder 43 moves upward. During the upward movement of the liquid cylinder 43, because the thin wall section 11 of the expansion pipe 1 in contact with the upper expansion cone 2 has a thin wall and weak strength, it is expanded first. Please refer to FIG. 9 , when the upper expansion cone 2 realizes the expansion of the thin-walled section 11 of the expansion tube 1 , the thickness of the thin-walled section 11 of the expansion tube 1 is smaller than that of the body section 10 of the expansion tube 1 . , when the expansion tube 1 of the thin-walled section 11 expands first, it will not fully adhere to the inner wall of the casing b. At this time, the entire expansion tube subsidy device is lifted up. Since the thin-walled section 11 of the expansion tube 1 can be blocked by the primary subsidy expansion tube 1a, the upper end of the expansion tube 1 according to the present invention can be limited, that is, in the secondary When subsidizing, the expansion tube of the present invention realizes seamless connection with the expansion tube 1a subsidized once. Then the force applying assembly 4 is moved upwards as a whole, thereby driving the lower expansion cone 3 to move upwards. When the lower expansion cone 3 is removed from the expansion tube 1, the lower expansion cone 3 completes the complete expansion of the expansion tube 1, and the expansion tube 1 realizes the repair of the casing to be repaired, and the expansion Afterwards, it completely adheres to the inner wall of the casing b, and has a good transition with the primary subsidized expansion tube 1a.

In another preferred embodiment, the composition and connection of the expansion tube subsidy device can be the same as in the first embodiment, the difference is that the maximum outer diameter of the upper expansion cone 2 is smaller than that of the lower expansion cone 3, that is, the expansion tube 1 expanded by the upper expansion cone 2 does not fully fit the casing b, at this time, the entire expansion tube subsidy device can be lifted up, and when it is blocked by the expansion tube 1 after one subsidy After that, the upper end of the expansion tube 1 of the present invention can be limited. Similarly, during the secondary subsidy, the expansion tube 1 of the present invention realizes seamless connection with the expansion tube 1a of the primary subsidy. Then the force applying assembly 4 is moved upwards as a whole, thereby driving the lower expansion cone 3 to move upwards. When the lower expansion cone 3 is removed from the expansion tube 1, the lower expansion cone 3 completes the complete expansion of the expansion tube 1, and the expansion tube 1 realizes the repair of the casing to be repaired, and the expansion Afterwards, it fits with the inner wall of the sleeve b, and has a good transition with the primary subsidized expansion tube 1a.

In a preferred embodiment, an anchor is installed between the piston tube 41 and the annulus of the expansion tube 1. On the one hand, it can ensure that the relative position of the expansion tube 1 and the piston tube 41 remains unchanged during the expansion process; When the length of the expansion tube 1 is relatively long, it can be used to ensure the rigidity of the expansion tube 1 .

Compared with the existing expansion tube subsidizing device, the expansion tube subsidizing device of the present invention cancels the bottom plug 3a, the high pressure chamber B and the sealing device 3a. The wall of the high-pressure chamber B is thin, but the internal pressure is high, so the strength is relatively poor, and leakage is prone to occur during the expansion process, which will reduce the success rate of expansion. The expansion tube 1 of the present invention can sit directly on the slope of the upper expansion cone 2 and the lower expansion cone 3, and the upper expansion cone 2 and the lower expansion cone 3 are respectively connected to the force application assembly 4; the upper expansion cone is realized through the above-mentioned structural improvement 2 and the lower expansion cone 3 are placed outside the expansion tube 1, and after the expansion tube 1 is expanded, a full-section metal seal is formed between the expansion tube 1 and the casing b. It not only simplifies the processing technology of the expansion tube, but also further improves the passability and expansion success rate of the expansion tube 1 .

The present invention not only effectively solves the problem that it is difficult to subsidize leakage points in casing damaged wells below the casing subsidy place after one subsidy, but further the present invention sets a thin-walled section 11 on the upper end of the expansion tube 1 or increases the maximum outer diameter of the upper expansion cone 2 It is set to be slightly smaller than the maximum outer diameter of the lower expansion cone 3, so as to realize the precise positioning of the position of the expansion tube 1 for the secondary subsidy, and realize the seamless connection between the expansion tube 1 of the secondary subsidy and the expansion tube of the primary subsidy, and the field application is good.

The above descriptions are only a few embodiments of the present invention. Although the disclosed embodiments of the present invention are as above, the content described above is only for the convenience of understanding the present invention, and is not intended to limit the present invention. Any person skilled in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention is Still, the scope defined by the appended claims shall prevail.

Claims (10)

1. An expansion tube subsidy device, characterized in that it comprises: an expansion tube, an upper expansion cone, a lower expansion cone, and a force application assembly, The expansion tube is a hollow column extending along the axis, and the column has a first port and a second port opposite to each other; The upper expansion cone and the lower expansion cone are provided with conical surfaces, and the respective conical surfaces of the upper expansion cone and the lower expansion cone are respectively stuck on the first port and the second port of the expansion tube; The force applying component can drive the upper expansion cone and the lower expansion cone to move toward each other along the axial direction of the expansion tube. 2. The expansion tube subsidizing device according to claim 1, characterized in that: the expansion tube is set in the subsidized casing, and in the direction perpendicular to the axis of the expansion tube, the thickness of both sides of the expansion tube The sum of the maximum outer diameter of the upper expansion cone and the lower expansion cone is greater than the inner diameter of the subsidized sleeve, and the maximum outer diameter of the upper expansion cone and the lower expansion cone is smaller than the inner diameter of the subsidized sleeve. 3. The expansion tube subsidizing device according to claim 2, characterized in that: the expanded outer diameter of the expansion tube is 0.1 mm to 0.8 mm larger than the inner diameter of the subsidized sleeve. 4. The expansion tube subsidizing device according to claim 1, characterized in that: the maximum outer diameter of the upper expansion cone and the lower expansion cone is not smaller than the outer diameter of the expansion tube. 5. The expansion tube subsidizing device according to claim 1, characterized in that, the force applying component is arranged in the hollow part of the expansion tube, which comprises: a piston tube, a piston disc, and a hydraulic cylinder, The piston tube is a hollow tube column, one end of which is located in the liquid cylinder and fixedly connected with the piston disk, and the other end protrudes out of the liquid cylinder and is fixedly connected with the upper expansion cone. There is also a flow hole communicating with the hydraulic cylinder; The piston disc is arranged in the liquid cylinder, and its diameter is the same as the inner diameter of the liquid cylinder; The liquid cylinder is arranged in the expansion tube, and a piston hole is opened on the upper surface of the liquid cylinder, and the piston tube passes through the piston hole. 6. The expansion tube subsidizing device according to claim 5, characterized in that: the center of the upper expansion cone is provided with a through first hole, and the piston tube in the force application assembly passes through the first hole and the first hole. The upper expansion cone is connected. 7. The expansion tube subsidizing device according to claim 5, characterized in that: a lower connecting rod is provided at the lower end of the liquid cylinder, one end of the lower connecting rod is connected with the liquid cylinder, and the other end is connected with the liquid cylinder. The expansion cone connection is described below. 8. The expansion tube subsidizing device according to claim 5, characterized in that: an anchor is provided between the piston tube and the annular space of the expansion tube. 9. The expansion tube subsidizing device according to claim 1, wherein the expansion tube comprises a body section and a thin-walled section extending outward from the body section, and the thin-walled section is in contact with the upper expansion cone, so that The wall thickness of the thin-walled section is smaller than the wall thickness of the expansion tube body section. 10. The expansion tube fitting device according to claim 1, characterized in that: the maximum outer diameter of the upper expansion cone is smaller than the maximum outer diameter of the lower expansion cone.