Cutting deblocking type packer

Abstract

The utility model discloses a cutting unblocking type packer which comprises a mandrel and a rubber sleeve assembly, a piston assembly, a slip assembly and a lower end assembly which are sequentially sleeved on the mandrel from top to bottom, the mandrel is provided with an overpressure hole and a clamping ring, the piston assembly is located outside the overpressure hole and is communicated with the overpressure hole, and two ends of the piston assembly are respectively connected with the rubber sleeve assembly and the slip assembly in a screwed mode. The lower end assembly is located outside the clamping ring groove and is in threaded connection with the slip assembly, one end of the mandrel is fixed into the lower end assembly, a limiting space and a cutting space exist between the mandrel and the lower end assembly and are located above and below the clamping ring, and one end of the slip assembly is located in the limiting space. By ingeniously designing the connection relation of all the assemblies, when the packer is cut and unsealed, the situation that parts fall off and fall into a well, and consequently burdens are caused to cleaning and salvaging in the well in the later period can be effectively prevented, the production cost is greatly reduced, the production efficiency is improved, the packer does not need to be milled during unsealing, all the assemblies can be recycled by replacing the mandrel after unsealing, and the production cost is reduced. And material waste is effectively avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of packers, in particular to a cutting and unsealing type packer. Background Art

[0002] In recent years, with the in-depth development of offshore or onshore oil and gas fields, multi-point mining and large-scale laying of derricks for drilling and producing crude oil have become the future trend. Therefore, the application of completion tools has also shown explosive growth. Packer is one of the conventional and widely used completion and production tools. Its super tensile strength and riveting ability play a vital role in the entire tool string and are the basis for ensuring normal underground operations.

[0003] In the prior art, packers mainly include recoverable and permanent types. Once a permanent packer is set, it cannot be unsealed. Although this type of packer has very good stability in specific applications, when a pipe string fails and the packer needs to be lifted out of the wellbore, the entire packer can only be milled off or milled off. When the slip part is milled, the remaining packer parts and the entire tail pipe fall to the bottom of the well, which puts a burden on the later cleaning and salvage of the wellbore, greatly increasing the manpower, time and economic costs. Utility Model Content

[0004] In view of the shortcomings of the prior art, the utility model provides a cutting and unsealing type packer, comprising:

[0005] The mandrel comprises an upper end joint, a center tube and a snap ring, wherein the upper end joint is arranged at the top of the center tube, and the side wall of the center tube has an overpressure hole and a snap ring groove in sequence from top to bottom, and the snap ring is installed in the snap ring groove; and

[0006] From top to bottom, the rubber cylinder assembly, piston assembly, slip assembly and lower end assembly are sequentially sleeved on the outside of the central tube, wherein the piston assembly is located outside the overpressure hole and is connected to the overpressure hole, and its two ends are respectively screwed to the rubber cylinder assembly and the slip assembly, the lower end assembly is located outside the retaining ring groove, and one end thereof is screwed to the slip assembly, one end of the central tube is fixed in the lower end assembly, and there is a limiting space and a cutting space between the outer wall of the central tube and the lower end assembly, the limiting space and the cutting space are respectively located above and below the retaining ring, and one end of the slip assembly is located in the limiting space and faces the retaining ring.

[0007] According to one embodiment of the utility model, the lower end component includes a connecting pipe, a lower end joint and a limiting clamping ring. The connecting pipe is located outside the clamping ring groove and is threadedly connected to the cava assembly. The limiting space and the cutting space are located between the connecting pipe and the center pipe. The inner wall of the lower end joint has a step surface. One end is sleeved on the connecting pipe and threadedly connected to the connecting pipe. The step surface forms a limiting ring groove on the connecting pipe. One end of the center pipe is located in the lower end joint, and its outer wall also has an annular clamping groove, which is opposite to the limiting ring groove. The limiting clamping ring is installed in the annular clamping groove and clamped in the limiting ring groove.

[0008] According to one embodiment of the utility model, the piston assembly includes a separator ring, a piston, a piston cylinder and a shear ring. The outer wall of the center tube is also provided with an installation groove, the overpressure hole is provided in the installation groove, the separator ring is installed in the installation groove, and the circumferential wall of the separator ring is provided with multiple overpressure openings. The piston cylinder sleeve is provided outside the separator ring, and one end thereof is screwed to the rubber cylinder assembly. The piston sleeve is provided outside the center tube and is located in the piston cylinder, one end of which is close to the separator ring, and the other end is exposed outside the piston cylinder and is screwed to the cava assembly. The shear ring sleeve is provided at one end of the piston located outside the piston cylinder, and it is screwed to the piston cylinder. A plurality of first shear pins are provided between the shear ring and the piston, and the plurality of first shear pins are arranged circumferentially along the shear ring, and the two ends of each first shear pin are respectively connected to the piston and the shear ring.

[0009] According to one embodiment of the utility model, the piston assembly also includes a first anti-backward structure, which includes an inner cava and an inner cava sleeve. The inner cava sleeve is arranged between the piston cylinder and the shear ring, and its two ends are screwed to the piston cylinder shear ring. The inner wall of the inner cava sleeve is provided with a first latch tooth. The inner cava sleeve is arranged outside the piston and is located inside the inner cava sleeve. The outer wall of the inner cava is provided with a second latch tooth corresponding to the first latch tooth, and the second latch tooth is engaged with the first latch tooth. The inner wall of the inner cava and the outer wall of the piston are both provided with anti-backward fine teeth, and the inner cava and the piston move relative to each other in one direction through the anti-backward fine teeth.

[0010] According to one embodiment of the utility model, the cava assembly includes, from top to bottom, an upper vertebral body, a cava and a lower vertebral body which are sleeved outside the central tube. The outer walls of the upper vertebral body and the lower vertebral body both have conical surfaces, and the conical surfaces of the two are arranged facing each other. The cava is also sleeved on one end of the upper vertebral body and the lower vertebral body, and its two ends are respectively abutted against the conical surfaces of the upper vertebral body and the lower vertebral body. The upper vertebral body is connected to the piston assembly, and the lower vertebral body is connected to the lower end assembly. The two ends of the outer wall of the cava have anchoring teeth.

[0011] According to one embodiment of the utility model, the cava assembly also includes a connecting ring, which is sleeved outside the center tube and located between the upper vertebral body and the piston assembly. One end of the connecting ring is screwed to the piston assembly, and the other end is located between the upper vertebral body and the center tube and screwed to the inner wall of the upper vertebral body. The outer wall of the center tube and the inner wall of the connecting ring are also provided with anti-backward fine teeth, and the connecting ring and the center tube can move in one direction through the anti-backward fine teeth.

[0012] According to one embodiment of the utility model, the outer wall of the upper vertebral body is provided with a plurality of first cone rings along its axial direction, and the outer wall of the lower vertebral body is provided with a plurality of second cone rings along its axial direction, both the first cone ring and the second cone ring have cone surfaces, and the cone surfaces of the two are arranged facing each other, and the inner wall of the cava is provided with a plurality of first extrusion grooves and a plurality of second extrusion grooves corresponding to the first cone ring and the second cone ring, respectively, wherein the cone surface corresponding to the first cone ring in each first extrusion groove has a first extrusion inclined surface, the first cone ring is clamped in the first extrusion groove, and its cone surface abuts against the first extrusion inclined surface, and each second extrusion groove is also provided with a second extrusion inclined surface corresponding to the second cone ring, and the second cone ring is clamped in the second extrusion groove, and its cone surface abuts against the second extrusion inclined surface.

[0013] According to one embodiment of the utility model, the rubber cylinder assembly slides between the upper end joint and the piston assembly, and it includes, from top to bottom, an upper rubber cylinder, a rubber cylinder spacer ring, a lower rubber cylinder and a rubber cylinder support sleeve which are sleeved outside the center tube, wherein the rubber cylinder support sleeve is threadedly connected to the piston assembly. When sealing, the two ends of the upper rubber cylinder respectively abut against the upper end joint and the rubber cylinder spacer ring, and the two ends of the lower rubber cylinder respectively abut against the rubber cylinder spacer ring and the rubber cylinder support sleeve.

[0014] According to one embodiment of the utility model, the rubber cylinder assembly also includes a sliding support sleeve, which is also sleeved on the outside of the central tube and is located between the upper end joint and the upper rubber cylinder for sliding. The sliding support sleeve is provided with a plurality of second shear pins along the circumferential direction, and each second shear pin is fixed at one end to the outer wall of the central tube and at the other end to the side wall of the sliding support sleeve.

[0015] According to one embodiment of the utility model, the outer wall of the center tube is also provided with a plurality of limiting grooves, which are circumferentially arranged on the outer wall of the center tube and located in the limiting space, each limiting groove is arranged axially along the center tube, and a plurality of first limiting screws are circumferentially installed on the side wall of the lower vertebral body, and one end of each first limiting screw is located in the limiting groove and slides along the limiting groove.

[0016] The beneficial effect of the utility model is that a limiting clamp ring is installed on the outer wall of the center tube located in the limiting space to limit the distance that the cava assembly slides downward, and at the same time, the lower end assembly is sleeved outside the lower end of the center tube and fixed at the lower end of the center tube, and the lower end assembly is screwed to the cava assembly. In this way, when the center tube is cut and located in the area of ​​the cutting space for unsealing, the cava assembly slides downward to be supported by the clamp ring, and at the same time, the cava assembly supports the piston assembly and the rubber cylinder assembly to prevent the above three from sliding down the well, and the lower end assembly is screwed to the cava assembly, and the lower part of the center tube is fixed in the lower end assembly, so the lower end assembly and the lower part of the center tube will not fall into the well. In this way, by cleverly designing the connection relationship between the components, it is effectively prevented that the parts fall off and fall into the well, which will cause a burden on the cleaning and salvage in the well later, greatly reducing the production cost and improving the production efficiency. Since there is no need to grind the packer to cause damage to the components, the center tube can be replaced and the components can be installed on the center tube for reuse, and at the same time, material waste can be effectively avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0018] Figure 1 It is a schematic diagram of the structure of the cutting and unsealing type packer in the embodiment;

[0019] Figure 2 It is a longitudinal cross-sectional view of a cutting and unsealing type packer in the embodiment;

[0020] Figure 3 for Figure 2 Enlarged view of middle part B;

[0021] Figure 4 for Figure 2 Enlarged view of middle F part;

[0022] Figure 5 It is an enlarged view of the G part in the embodiment;

[0023] Figure 6 is a longitudinal cross-sectional view of the lower end assembly in the embodiment;

[0024] Figure 7 It is a radial cross-sectional view of the center tube, the separation ring and the piston cylinder in the embodiment;

[0025] Figure 8 for Figure 2 Enlarged view of the middle D part;

[0026] Fig. 9 for Figure 2 Enlarged view of middle E part;

[0027] Fig.10 It is a longitudinal cross-sectional view of the explosion structure of the upper vertebral body, slips and lower vertebral body in the embodiment;

[0028] Fig.11 for Figure 2 Enlarged view of middle C;

[0029] Fig.12 for Figure 1 Enlarged view of part A in the middle. DETAILED DESCRIPTION

[0030] The following will disclose multiple embodiments of the present invention with drawings. For the purpose of clear description, many practical details will be described together in the following description. However, it should be understood that these practical details should not be used to limit the present invention. In other words, in some embodiments of the present invention, these practical details are not necessary. In addition, in order to simplify the drawings, some conventional structures and components will be depicted in a simple schematic manner in the drawings.

[0031] In addition, in the present utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes, and do not specifically refer to the order or sequence, nor are they used to limit the present utility model. They are only used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0032] See also Figure 1-Figure 5 , Figure 1 This is a schematic diagram of the structure of the cutting and unsealing type packer in the embodiment. Figure 2 This is a longitudinal cross-sectional view of a cutting and unsealing type packer in the embodiment. Figure 3 for Figure 2 Enlarged view of part B in the middle. Figure 4 for Figure 2 Enlarged view of the middle F part, Figure 5The enlarged view of the G part in the embodiment. A cutting and unsealing type packer in this embodiment includes a core shaft 1, a rubber cartridge assembly 2, a piston assembly 3, a slip assembly 4 and a lower end assembly 5, wherein the core shaft 1 includes an upper end joint 11, a center ring 12 and a snap ring 13, the upper end joint 11 is arranged at the top of the center pipe 12, the side wall of the center pipe 12 is provided with an overpressure hole 121 and a snap ring groove 122 from top to bottom, the snap ring 13 is installed in the snap ring groove 122, the rubber cartridge assembly 2, the piston assembly 3, the slip assembly 3 and the lower end assembly 5 are sequentially sleeved on the outside of the center pipe 12 from top to bottom, and the piston assembly 13 is provided on the bottom of the center pipe 12. Component 3 is located outside the overpressure hole 121, the lower end component 5 is located outside the retaining ring groove 122, one end of which is screwed to the cava component 4, and one end of the center pipe 12 is fixed in the lower end component 5, thereby providing traction for the lower end component 5 so that the lower end component 5 and the center pipe 12 cannot be displaced relative to each other. There is a limiting space 51 and a cutting space 52 between the outer wall of the center pipe 12 and the lower end component 5, and the limiting space 51 and the cutting space 52 are respectively located above and below the retaining ring 13, and one end of the cava component 4 is located in the limiting space 51 and faces the retaining ring 13.

[0033] During operation, the oil pipe and the tool string are connected through the upper end joint 11 and the lower end assembly 11 respectively to form an oil and gas pipe string, and pressure is applied to the pipe string. The pressure enters the overpressure hole 121 through the center pipe 12, and enters the piston assembly 3 through the pressure transmission hole 121, so that the two ends of the piston assembly 3 squeeze the rubber sleeve assembly 2 and the slip assembly 4 respectively. At this time, the rubber sleeve assembly 2 is squeezed to abut against the upper end joint 11, thereby radial expansion occurs. The other end of the slip assembly 4 is fixed by the lower end assembly 5, and its two ends are squeezed by the piston assembly 3 and the lower end assembly 5 respectively, and also expand radially, so that the slip assembly 4 bites into the downhole pipe wall, and the rubber sleeve assembly 2 also abuts against the downhole pipe wall, realizing the permanent sealing of the packer.

[0034] When unsealing is required, a cutting tool is used to lower the pipe string and enter the center pipe 12. When the cutting tool reaches the area of ​​the center pipe located in the cutting space 52, the center pipe 12 is cut into an upper and a lower part, so that the lower part of the center pipe 12 cannot provide traction for the lower end component 5, causing the lower end component 5 to slide downward. During the process, the lower end component 5 drives the slip assembly 4, the piston assembly 3 and the rubber cylinder assembly 2 to slide downward along the upper part of the center pipe 12, thereby causing both ends of the slip assembly 4 and the rubber cylinder assembly 2 to lose the abutment force and contract radially to achieve unsealing. When the slip assembly 4 slides to the retaining ring 13, it is restricted by the retaining ring 13 and cannot continue to slide. The piston assembly 3 and the rubber cylinder assembly 2 are unable to continue to slide. It can be understood that since the lower end assembly 5 is screwed to the cava assembly 4 and the lower part of the center tube 12 is fixed in the lower end assembly 5, the lower end assembly 5 and the lower part of the center tube 12 will not fall into the well. In this way, when the packer is unsealed and taken out from the well, it can effectively prevent parts from falling off and falling into the well and causing a burden on the subsequent cleaning and salvage of the well, greatly reducing production costs and improving production efficiency. Since there is no need to grind the packer to cause damage to the components, the center tube 12 can be replaced and the components can be installed on the center tube 12 for reuse, and at the same time, material waste can be effectively avoided.

[0035] See also Figure 6 , review Figure 1-Figure 5 , Figure 6 1 is a longitudinal cross-sectional view of the lower end assembly in the embodiment. Specifically, the lower end assembly 5 includes a connecting pipe 53, a lower end joint 54 and a limiting snap ring 55. The connecting pipe 53 is located outside the snap ring groove 122 and is screwed to the slip assembly 4. The limiting space 51 and the cutting space 52 are located between the connecting pipe 53 and the center pipe 12. The inner wall of the lower end joint 54 has a step surface, one end of which is sleeved on the connecting pipe 53 and screwed to the connecting pipe 53. The step surface forms a limiting ring groove 56 on the connecting pipe 53. One end of the center pipe 12 is located in the lower end joint 54, and its outer wall also has an annular snap groove 125, which is opposite to the limiting ring groove 56. The limiting snap ring 55 is installed in the annular snap groove 125 and is snapped in the limiting ring groove 56. In this way, during installation, after one end of the connecting pipe 53 is screwed to the cava component 4, the retaining ring 13 is installed in the retaining ring groove 122, and one side of it is abutted against the other end of the connecting pipe 53, and then the lower end joint 54 is sleeved on the outside of one end of the connecting pipe 53 and screwed thereto. At this time, the step surface and one end of the connecting pipe 53 jointly form a limiting ring groove 56, that is, at this time, the retaining ring 13 is respectively clamped in the retaining ring groove 122 and the limiting ring groove 56, thereby realizing the fixation of the center pipe 12 to the lower end component 5. At the same time, it also facilitates the installation of the lower end component 5 to improve the convenience of product use.

[0036] Preferably, the inner wall of the connecting pipe 53 and the inner wall of the lower end joint 54 are respectively provided with a first abutment ring 531 and a second abutment ring 541. After the lower end component 5 is installed, the first abutment ring 531 is located below the clamping ring 13 and abuts against the clamping ring 13, and the second abutment ring 541 is located below the center pipe 12 and abuts against the lower end of the center pipe 12. In this way, when the lower end component 5 is subjected to the upward force from the well, the first abutment ring 531 and the second abutment ring 541 can effectively disperse the upward force from the limiting clamping ring 55 to the clamping ring 13 and the center pipe 12, thereby preventing the limiting clamping ring 55 from failing and ensuring the stability of the packer.

[0037] See also Figure 7-Figure 8 , review Figure 1-Figure 5 , Figure 7 This is a radial cross-sectional view of the center tube, the separation ring and the piston cylinder in the embodiment. Figure 8 for Figure 2 Enlarged view of part D in the middle. Furthermore, the piston assembly 3 includes a separator ring 31, a piston 32, a piston cylinder 33 and a shear ring 34. The outer wall of the center tube 12 is also provided with a mounting groove 123. The overpressure hole 121 is provided in the mounting groove 123. The separator ring 31 is installed in the mounting groove 123. The peripheral wall of the separator ring 31 is provided with a plurality of overpressure openings 311. The piston cylinder 33 is sleeved outside the separator ring 31, and one end thereof is screwed to the rubber cylinder assembly 2. The piston 33 is sleeved outside the center tube 12 and located in the piston cylinder 33, one end of which is close to the separator ring 31, and the other end is exposed outside the piston cylinder 33 and screwed to the cava assembly 4. The shear ring 34 is sleeved on one end of the piston 32 located outside the piston cylinder 33, and is screwed to the piston cylinder 33. A plurality of first shear pins 341 are provided between the shear ring 34 and the piston 32. The plurality of first shear pins 341 are arranged circumferentially along the shear ring 34, and the two ends of each first shear pin 341 are respectively connected to the piston 32 and the shear ring 34. Specifically, the inner wall of the separating ring 31 and the bottom wall of the mounting groove 123 form a first pressure transmission chamber 01, and the first pressure transmission chamber 01 is connected to the overpressure hole 121. The outer wall of the separating ring 31 and the inner wall of the piston 32 form a second pressure transmission chamber 02, and the second pressure transmission hole 02 is connected to the first pressure transmission chamber 01 through the overpressure opening 311. In this way, after the pressure enters the first pressure transmission chamber 01 through the overpressure hole 121, it enters the second overpressure chamber 02 through multiple overpressure openings 311, and evenly pushes the piston cylinder 33 and the piston 32 to both ends. At the same time, the piston cylinder 33 pulls the shear ring 34 and the piston 32 to perform opposite movements. At this time, the first shear pin 341 is sheared off due to the shear force generated by the opposite movements of the piston 32 and the shear ring 34, so that the piston cylinder 33 pushes and squeezes the rubber cylinder assembly 2 upward, causing the rubber cylinder assembly 2 to expand radially. Similarly, the piston 32 pushes and pressurizes the cava assembly 4 downward, causing the cava assembly 4 to expand radially, completing the sealing.

[0038] Furthermore, the piston assembly 3 also includes a first anti-backward structure 35, which includes an inner cava 351 and an inner cava sleeve 352. The inner cava sleeve 352 is arranged between the piston cylinder 33 and the shear ring 34, and its two ends are screwed to the shear ring 34 of the piston cylinder 33. Its inner wall is provided with a first latch tooth 3521. The inner cava 351 is sleeved on the outside of the piston 32 and is located in the inner cava sleeve 352. Its outer wall is provided with a second latch tooth 3511 corresponding to the first latch tooth 3521. The second latch tooth 3511 is engaged with the first latch tooth 3521. The inner wall of the inner cava 351 and the outer wall of the piston 32 are both provided with anti-backward fine teeth 03. The anti-backward fine teeth 03 are all unidirectional teeth. The inner cava 351 and the piston 32 move relative to each other in one direction through the anti-backward fine teeth, wherein the teeth of the anti-backward fine teeth 03 located on the outer wall of the piston 32 are facing upward. When the piston cylinder 33 moves upward, it pulls the inner cava sleeve 342 and the shear ring 34 to move synchronously. During the process, the inner cava sleeve 352 also drives the inner cava 351 to move along the outer wall of the piston 32, so that the inner cava 351 and the retraction fine teeth 03 of the piston 32 engage with each other, thereby limiting the piston cylinder 33 and the piston 32 to prevent the piston cylinder 33 from retreating, that is, preventing the rubber cylinder assembly from rebounding after pressure relief and failing to achieve the sealing effect.

[0039] Preferably, in a specific implementation, when the anti-backward structure 35 is installed, the inner cava 351 and the inner cava sleeve 352 can be connected by riveting in the anti-rotation pin 04 to prevent the two from rotating relative to each other.

[0040] See also Figure 9-10 , review Figure 1-Figure 2 and Figure 8 , Fig. 9 for Figure 2 Enlarged view of middle E part, Fig.10 4 is a longitudinal cross-sectional view of the explosion structure of the upper vertebra, slips and lower vertebra in the embodiment. Further, the slip assembly 4 includes, from top to bottom, an upper vertebra 41, a slip 42 and a lower vertebra 43 which are sleeved outside the central tube 12. The outer walls of the upper vertebra 41 and the lower vertebra 43 both have conical surfaces, and the conical surfaces of the two are arranged facing each other. The slip 42 is also sleeved on one end of the upper vertebra 41 and the lower vertebra 43, and its two ends are respectively in contact with the conical surfaces of the upper vertebra 41 and the lower vertebra 43. The upper vertebra 41 is connected to the piston assembly 3, and the lower vertebra 41 is connected to the lower end assembly 5. The two ends of the outer wall of the slip 42 have anchoring teeth 421. When setting, the piston 32 pushes the upper vertebra 41 downward, so that the upper vertebra 41 squeezes the slip 42 toward the lower vertebra 43. Since the lower vertebra 43 is restricted by the lower end assembly 5 and is fixed, the lower vertebra 43 and the upper vertebra 41 will squeeze the slip 42 together, and the conical surfaces of the upper vertebra 41 and the lower vertebra 43 gradually cause the slip 42 to expand radially, so that the anchoring teeth 421 of the slip 42 bite into the downhole pipe wall to achieve setting. In this example, the anchoring teeth 421 at both ends of the slip 42 adopt a bidirectional tooth shape, that is, the anchoring teeth 421 at both ends of the slip 42 are inclined toward the center line aa.

[0041] Furthermore, the cava assembly 4 also includes a connecting ring 44, which is sleeved on the outside of the center tube 12 and located between the upper vertebral body 41 and the piston assembly 3. One end of the connecting ring 44 is screwed to the piston assembly 3, and the other end is located between the upper vertebral body 41 and the center tube 12 and screwed to the inner wall of the upper vertebral body 41. The outer wall of the center tube 12 and the inner wall of the connecting ring 44 are also provided with anti-backward fine teeth 03. The connecting ring 44 and the center tube 12 can move unidirectionally through the anti-backward fine teeth 03, wherein the teeth of the backward fine teeth 03 located on the center tube 12 are facing downward. Similarly, when sealing, the piston pushes the connecting ring 44 downward, so that the connecting ring 44 squeezes the upper vertebral body 41 downward. During the process, the anti-backward fine teeth 03 of the connecting ring 44 and the center tube 12 gradually bite to prevent the connecting ring 44 from retreating, thereby preventing the cava assembly from rebounding after pressure relief and causing failure to seal.

[0042] Preferably, in this example, when the cava assembly 4 is installed, anti-rotation pins 04 are also riveted into the cava 42 to connect the upper vertebra 41 and the cava 42 to the lower vertebra 43, respectively, to prevent the cava 42 from rotating relative to the upper vertebra 41 and the lower vertebra 42, thereby ensuring the stability of the product.

[0043] Preferably, the outer wall of the upper vertebral body 41 is provided with a plurality of first cone rings 411 along its axial direction, and the outer wall of the lower vertebral body 43 is provided with a plurality of second cone rings 431 along its axial direction. Both the first cone ring 411 and the second cone ring 431 have cone surfaces, and the cone surfaces of the two are arranged facing each other. The inner wall of the slip 42 is provided with a plurality of first extrusion grooves 422 and a plurality of second extrusion grooves 423 corresponding to the first cone ring 411 and the second cone ring 431, respectively, wherein the cone surface corresponding to the first cone ring 411 in each first extrusion groove 422 has a first extrusion inclined surface 4221, the first cone ring 411 is clamped in the first extrusion groove 422, and its cone surface abuts against the first extrusion inclined surface 4221, and each second extrusion groove 423 is also provided with a second extrusion inclined surface 4231 corresponding to the second cone ring 431, and the second cone ring 431 is clamped in the second extrusion groove 423, and its cone surface abuts against the second extrusion inclined surface 4231. In this way, when the upper vertebral body 41 and the lower vertebral body 43 jointly squeeze the slip 42, the conical surfaces of the first cone ring 411 and the second cone ring 431 located in the first extrusion groove 422 and the second extrusion groove 423 simultaneously squeeze the first extrusion inclined surface 4221 and the second extrusion inclined surface 4231, so that the radial expansion of the slip 42 is more uniform, thereby improving the stability of the slip 42.

[0044] Review again Figure 4Preferably, the outer wall of the central tube 12 is further provided with a plurality of limiting grooves 124, which are arranged circumferentially on the outer wall of the central tube 12 and located in the limiting space 51, and each limiting groove 124 is arranged axially along the central tube 12, and a plurality of first limiting screws 432 are circumferentially installed on the side wall of the lower vertebral body 43, and one end of each first limiting screw 432 is located in the limiting groove 124 and slides along the limiting groove 124. In this way, the lower vertebral body 43 can slide axially along the central tube 12, and the relative rotation between the lower vertebral body 43 and the central tube 12 can be effectively limited, and the relative rotation between the slip assembly 4 and the central tube 12 can be prevented as a whole.

[0045] See also Figure 11-Figure 12 , review Figure 1-Figure 2 , Fig.11 for Figure 2 Enlarged view of the middle C part, Fig.12 for Figure 1 Enlarged view of the middle A part. The rubber cylinder assembly 2 slides between the upper end joint 11 and the piston assembly 3, and includes, from top to bottom, an upper rubber cylinder 21 sleeved outside the central tube 12, a rubber cylinder spacer 22, a lower rubber cylinder 23 and a rubber cylinder support sleeve 24, wherein the rubber cylinder support sleeve 24 is threadedly connected to the piston assembly 3. When setting, the two ends of the upper rubber cylinder 21 abut against the upper end joint 11 and the rubber cylinder spacer 22, respectively, and the two ends of the lower rubber cylinder 23 abut against the rubber cylinder spacer 22 and the rubber cylinder support sleeve 24, respectively. Specifically, one end of the rubber cylinder support sleeve 34 is located in the piston cylinder 33 and is threadedly connected to the inner wall of the piston cylinder 33. When the seal is set, the pressure enters the second pressure transmission chamber 02 in the piston cylinder 33 and pushes the rubber cylinder support sleeve 24 upward. In the rubber cylinder assembly 2, as the rubber cylinder support sleeve 24 is pushed up, the upper rubber cylinder 21, the rubber cylinder spacer ring 22 and the lower rubber cylinder 23 all slide upward along the center tube 12 until one end of the upper rubber cylinder 21 abuts against the upper end joint 11. At this time, the upper end joint 11 and the rubber cylinder support sleeve 24 jointly squeeze the upper The rubber cylinder 21, rubber cylinder spacer ring 22 and lower rubber cylinder 23 cause the upper rubber cylinder 21 and the lower rubber cylinder 23 to expand radially and abut against the downhole pipe wall to achieve sealing. During the process, the rubber cylinder support sleeve 24 simultaneously pulls the piston cylinder 33 to move upward, so that the inner cava sleeve 352 drives the inner cava sleeve 351 to move upward, so that the anti-backward fine teeth 03 of the inner cava 351 and the anti-backward fine teeth 03 on the outer wall of the piston 32 engage with each other to prevent the upper rubber cylinder 21 and the lower rubber cylinder 23 from radially shrinking and rebounding when the pressure is released.

[0046] Preferably, the rubber cylinder assembly 2 also includes a sliding support sleeve 25, which is also sleeved on the outside of the center tube 12 and is located between the upper end joint 11 and the upper rubber cylinder 21. The sliding support sleeve 25 is provided with a plurality of second shear pins 251 along the circumferential direction, and each second shear pin 251 is fixed at one end to the outer wall of the center tube 12 and at the other end to the side wall of the sliding support sleeve 25, thereby fixing the sliding support sleeve 25 to the outer wall of the center tube 12 to prevent the rubber cylinder assembly 2 from shaking along the circumferential direction of the center tube 12 before sealing and causing damage. During sealing, as the rubber cylinder support sleeve 24 is pushed up, one end of the upper rubber cylinder 21 abuts against the sliding support sleeve 25, so that the second shear pin 251 is sheared off, and the sliding support sleeve 25 moves up to abut against the upper end joint 11. At this time, the sliding support sleeve 25, the upper rubber cylinder 21, the rubber cylinder spacer ring 22 and the lower rubber cylinder 23 are squeezed against each other, thereby causing the upper rubber cylinder 21 and the lower rubber cylinder 23 to expand radially to achieve sealing.

[0047] Among them, one end of the upper rubber cylinder 21 facing the sliding support sleeve 25 and one end of the lower rubber cylinder 23 facing the rubber cylinder support sleeve 24 are both provided with a rubber cylinder back ring 26. Preferably, the rubber cylinder back ring 26 adopts a double back ring to increase the load that the rubber cylinder assembly 2 can withstand and prevent the rubber cylinder assembly 2 from being crushed by the downhole pressure, causing the entire sealing system of the packer to fail.

[0048] Preferably, the sliding support sleeve 25 is also provided with a plurality of strip sliding holes 252, and the plurality of strip sliding holes 252 are circumferentially arranged on the side wall of the sliding support sleeve 25, and are alternately arranged with a plurality of second shear pins 251, and each strip sliding hole 252 is axially arranged on the sliding support sleeve 25, and the rubber cylinder assembly 2 also includes a plurality of second limit screws 27, one end of the plurality of second limit screws 27 is located in the strip sliding hole 252, and the other end is fixed to the outer wall of the center tube 12, so that the sliding support sleeve 25 can slide axially along the center tube 12 while effectively preventing the sliding support sleeve 25 and the center tube 12 from rotating relative to each other.

[0049] Review Figure 1-Figure 2 In this example, a connecting thread 111 is further provided on the inner wall of the upper end joint 11. Preferably, the connecting thread 111 is a single-sided serrated right-angle thread with the right-angle surface facing downward, which is convenient for reinsertion of the upper end pipe string after sealing, thereby improving the convenience of use.

[0050] In summary, in this example, a limiting clamp ring is installed on the outer wall of the center tube located in the limited space to limit the distance that the cava assembly slides downward, and at the same time, the lower end assembly is sleeved on the outside of the lower end of the center tube and fixed at the lower end of the center tube, and the lower end assembly is screwed to the cava assembly. In this way, when the center tube is cut and located in the area of ​​the cutting space for unsealing, the cava assembly slides downward to be supported by the clamp ring, and at the same time, the cava assembly supports the piston assembly and the rubber cylinder assembly to prevent the above three from sliding into the well, and the lower end assembly is screwed to the cava assembly, and the lower part of the center tube is fixed in the lower end assembly, so the lower end assembly and the lower part of the center tube will not fall into the well. In this way, it can effectively prevent parts from falling off and falling into the well, which will cause a burden on the subsequent cleaning and salvage of the well, greatly reduce production costs, and improve production efficiency. Since there is no need to grind the packer to damage the components, the center tube can be replaced and the components can be installed on the center tube for reuse, and material waste can be effectively avoided.

[0051] The above is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the claims of the present invention.

Claims

1. A cutting and unsealing type packer, characterized in that: include: A mandrel, comprising an upper end joint, a center tube and a snap ring, wherein the upper end joint is arranged at the top end of the center tube, the side wall of the center tube has an overpressure hole and a snap ring groove in sequence from top to bottom, and the snap ring is installed in the snap ring groove; and From top to bottom, the rubber cylinder assembly, piston assembly, slip assembly and lower end assembly are sequentially sleeved on the outside of the central tube, wherein the piston assembly is located outside the overpressure hole and communicated with the overpressure hole, and its two ends are respectively screwed to the rubber cylinder assembly and the slip assembly, the lower end assembly is located outside the retaining ring groove, and one end of the lower end assembly is screwed to the slip assembly, one end of the central tube is fixed in the lower end assembly, and there is a limiting space and a cutting space between the outer wall of the central tube and the lower end assembly, the limiting space and the cutting space are respectively located above and below the retaining ring, and one end of the slip assembly is located in the limiting space and faces the retaining ring.

2. The cutting and unsealing type packer according to claim 1, characterized in that: The lower end component includes a connecting pipe, a lower end joint and a limiting clamping ring. The connecting pipe is located outside the clamping ring groove and is screwed to the cava assembly. The limiting space and the cutting space are located between the connecting pipe and the center pipe. The inner wall of the lower end joint has a step surface. One end is sleeved on the connecting pipe and is screwed to the connecting pipe. The step surface forms a limiting ring groove on the connecting pipe. One end of the center pipe is located in the lower end joint, and its outer wall also has an annular clamping groove. The annular clamping groove is opposite to the limiting ring groove. The limiting clamping ring is installed in the annular clamping groove and clamped in the limiting ring groove.

3. The cutting and unsealing type packer according to claim 1, characterized in that: The piston assembly includes a separator ring, a piston, a piston cylinder and a shear ring. The outer wall of the center tube is also provided with a mounting groove, and the overpressure hole is provided in the mounting groove. The separator ring is installed in the mounting groove, and the circumferential wall of the separator ring is provided with a plurality of overpressure openings. The piston cylinder sleeve is provided outside the separator ring, and one end of the piston cylinder is screwed to the rubber cylinder assembly. The piston sleeve is provided outside the center tube and located in the piston cylinder, one end of the piston cylinder is close to the separator ring, and the other end is exposed outside the piston cylinder and screwed to the cava assembly. The shear ring sleeve is provided at one end of the piston located outside the piston cylinder, and is screwed to the piston cylinder. A plurality of first shear pins are provided between the shear ring and the piston, and the plurality of first shear pins are arranged circumferentially along the shear ring, and the two ends of each first shear pin are respectively connected to the piston and the shear ring.

4. The cutting and unsealing type packer according to claim 3, characterized in that: The piston assembly also includes a first anti-backward structure, which includes an inner cava and an inner cava sleeve. The inner cava sleeve is arranged between the piston cylinder and the shear ring, and its two ends are screwed to the shear ring of the piston cylinder, and its inner wall is provided with a first latch tooth. The inner cava sleeve is arranged outside the piston and is located inside the inner cava sleeve. Its outer wall is provided with a second latch tooth corresponding to the first latch tooth, and the second latch tooth is engaged with the first latch tooth. The inner wall of the inner cava and the outer wall of the piston are both provided with anti-backward fine teeth, and the inner cava and the piston move relative to each other in one direction through the anti-backward fine teeth.

5. The cutting and releasing type packer according to claim 1, characterized in that: The slip assembly includes, from top to bottom, an upper vertebral body, a slip and a lower vertebral body which are sleeved outside the central tube. The outer walls of the upper vertebral body and the lower vertebral body both have conical surfaces, and the conical surfaces of the two are arranged facing each other. The slip is also sleeved on one end of the upper vertebral body and the lower vertebral body, and its two ends are respectively abutted against the conical surfaces of the upper vertebral body and the lower vertebral body. The upper vertebral body is connected to the piston assembly, and the lower vertebral body is connected to the lower end assembly. The two ends of the outer wall of the slip have anchoring teeth.

6. The cutting and releasing type packer according to claim 5, characterized in that: The slip assembly also includes a connecting ring, which is sleeved outside the center tube and located between the upper vertebral body and the piston assembly. One end of the connecting ring is screwed to the piston assembly, and the other end is located between the upper vertebral body and the center tube and screwed to the inner wall of the upper vertebral body. The outer wall of the center tube and the inner wall of the connecting ring are also provided with anti-backward fine teeth, and the connecting ring and the center tube can move unidirectionally through the anti-backward fine teeth.

7. The cutting and releasing type packer according to claim 5, characterized in that: The outer wall of the upper vertebral body is provided with a plurality of first cone rings along its axial direction, and the outer wall of the lower vertebral body is provided with a plurality of second cone rings along its axial direction. Both the first cone ring and the second cone ring have cone surfaces, and the cone surfaces of the two are arranged facing each other. The inner wall of the slip is provided with a plurality of first extrusion grooves and a plurality of second extrusion grooves corresponding to the first cone ring and the second cone ring, respectively, wherein the cone surface corresponding to the first cone ring in each first extrusion groove has a first extrusion inclined surface, the first cone ring is clamped in the first extrusion groove, and its cone surface abuts against the first extrusion inclined surface, and each second extrusion groove is also provided with a second extrusion inclined surface corresponding to the second cone ring, and the second cone ring is clamped in the second extrusion groove, and its cone surface abuts against the second extrusion inclined surface.

8. The cutting and releasing type packer according to claim 1, characterized in that: The rubber cylinder assembly slides between the upper end joint and the piston assembly, and includes, from top to bottom, an upper rubber cylinder, a rubber cylinder spacer ring, a lower rubber cylinder and a rubber cylinder support sleeve which are sleeved outside the center tube, wherein the rubber cylinder support sleeve is threadedly connected to the piston assembly. When sealing, the two ends of the upper rubber cylinder respectively abut against the upper end joint and the rubber cylinder spacer ring, and the two ends of the lower rubber cylinder respectively abut against the rubber cylinder spacer ring and the rubber cylinder support sleeve.

9. The cutting and releasing type packer according to claim 8, characterized in that: The rubber cylinder assembly also includes a sliding support sleeve, which is also sleeved on the outside of the central tube and is slidably located between the upper end joint and the upper rubber cylinder. The sliding support sleeve is circumferentially provided with a plurality of second shear pins, and each second shear pin has one end fixed to the outer wall of the central tube and the other end fixed to the side wall of the sliding support sleeve.

10. The cutting and releasing type packer according to claim 5, characterized in that: The outer wall of the center tube is also provided with a plurality of limiting grooves, which are circumferentially arranged on the outer wall of the center tube and located in the limiting space, each limiting groove is arranged axially along the center tube, and the side wall of the lower vertebral body is circumferentially installed with a plurality of first limiting screws, one end of each first limiting screw is located in the limiting groove and slides along the limiting groove.

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