A dual rubber borehole packer

Abstract

The application discloses a double rubber-bushing bare hole packer, which comprises a pressing mechanism and an expansion mechanism; the pressing mechanism comprises a lower piston ring and a lower piston sleeve; the lower piston ring is slidably sleeved on a central pipe; one end of the lower piston sleeve is slidably and sealingly sleeved on the lower piston ring, and the other end of the lower piston sleeve is slidably and sealingly sleeved on the central pipe; a first oil injection cavity in communication with a first oil leakage hole is formed between the lower piston ring and the lower piston sleeve; the expansion mechanism comprises two rubber-bushing assemblies, which are respectively installed on two ends of the central pipe and connected with the lower piston ring and the lower piston sleeve. The beneficial effects of the technical scheme are as follows: the double rubber-bushing design can greatly increase the length of a sealing section, and even if a long crack section is encountered, the sealing effect can be achieved, and the use requirements of super-deep, super-high-temperature and super-high-pressure wells can be met.

Description

Technical Field

[0001] This invention relates to the field of packer technology, and in particular to a double-tube naked-eye packer. Background Technology

[0002] With the continuous development of drilling and production technology, the operating conditions of oil extraction are becoming increasingly complex. In ultra-deep, ultra-high temperature, and ultra-high pressure wells, the open-hole packer-based staged fracturing design is often limited by the rated pressure and temperature of completion tools, thus restricting the effectiveness of the fractures. Especially in tight formations with pressures exceeding 70 MPa, there are higher requirements for the overall production efficiency, operational efficiency, and reduction of specialized time. Open-hole packers are available from various companies both domestically and internationally, mainly focusing on 70 MPa and 177°C product structures. However, open-hole packers with a temperature resistance of 204°C and a pressure resistance of 103.4 MPa are only recently being designed by top-tier international companies. Furthermore, ultra-high temperature and high pressure open-hole packers account for less than 5% of the market share internationally. As wells are drilled deeper, the inevitable result is ultra-high temperature, high pressure, and large enlargement rates in the wellbore. The technical requirements for large enlargement rates may need to reach 8% or even higher.

[0003] Open-hole packers are an essential segmentation tool in the open-hole oil and gas well stratification process. At the same time, high pressure, high temperature, and high hydrogen sulfide content in ultra-deep wells pose new challenges to the high temperature and high pressure resistance of open-hole packers.

[0004] Most existing open-hole packers adopt a single-tube design. The disadvantage of the single-tube design is that its sealing section is relatively short (usually less than 50 cm). When the sealing position is exactly located in a fracture as long as 1 meter, fluid can be directly conducted through the fracture, which cannot meet the requirements of ultra-deep, ultra-high temperature and ultra-high pressure wells. Summary of the Invention

[0005] In view of this, it is necessary to provide a dual-tube open-hole packer to solve the technical problems of poor plugging effect of existing open-hole packers and inability to meet the application requirements of ultra-deep, ultra-high temperature and ultra-high pressure wells.

[0006] To achieve the above objectives, the present invention provides a double-tube open-eye packer, comprising a packer body, the packer body including a central tube, a first oil discharge hole being provided on the side wall of the central tube, and the double-tube open-eye packer further including a compression mechanism and an expansion mechanism;

[0007] The extrusion mechanism includes a lower piston ring and a lower piston sleeve. The lower piston ring is slidably sleeved on the central tube. One end of the lower piston sleeve is slidably and sealingly sleeved on the lower piston ring, and the other end is slidably and sealingly sleeved on the central tube. A first oil injection chamber communicating with the first oil drain hole is formed between the lower piston ring and the lower piston sleeve.

[0008] The expansion mechanism includes two rubber cylinder assemblies, which are respectively installed at both ends of the central tube and connected to the lower piston ring and the lower piston sleeve.

[0009] In some embodiments, a second oil discharge hole is also provided on the side wall of the central tube. The extrusion mechanism further includes an upper piston ring and an upper piston sleeve. The upper piston ring is slidably sleeved on the central tube and fixedly connected to the lower piston ring. One end of the upper piston sleeve is slidably sleeved on the lower piston ring, and the other end of the upper piston sleeve is slidably sleeved on the upper piston ring. The upper piston sleeve and the lower piston sleeve are threadedly fixedly connected. A second oil injection chamber communicating with the second oil discharge hole is formed between the upper piston ring and the upper piston sleeve.

[0010] In some embodiments, the upper piston sleeve and the lower piston sleeve are threadedly fixedly connected and fixedly connected by a plurality of first fixing screws.

[0011] In some embodiments, the upper piston ring and the upper piston sleeve are fixedly connected via a first shear pin.

[0012] In some embodiments, the central tube includes an upper central tube and a lower central tube that are coaxially and fixedly connected, and the two rubber sleeve assemblies are an upper rubber sleeve assembly and a lower rubber sleeve assembly, which are respectively installed on the upper central tube and the lower central tube.

[0013] In some embodiments, the upper rubber sleeve assembly includes a plurality of upper spacer rings and a plurality of upper telescopic bodies, the upper spacer rings and the upper telescopic bodies are arranged alternately, each of the upper telescopic bodies is movably connected to the adjacent upper spacer ring, and the upper telescopic body located at the lowermost end is fixedly connected to the upper piston ring.

[0014] In some embodiments, the upper rubber sleeve assembly further includes a guide ring, which is slidably sleeved on the upper central tube. One end of the guide ring is fixedly connected to the lowermost upper telescopic body, and the other end of the guide ring is fixedly connected to the upper piston ring. The guide ring is fixedly connected to the upper central tube via a plurality of second shear pins. The packer body further includes an upper connector, which is fixed to the upper end of the upper central tube and abuts against the uppermost upper telescopic body.

[0015] In some embodiments, the lower rubber sleeve assembly includes a plurality of lower spacer rings and a plurality of lower telescopic bodies, the lower spacer rings and the lower telescopic bodies are arranged alternately, each of the lower telescopic bodies is movably connected to the adjacent lower spacer ring, and the uppermost lower telescopic body is fixedly connected to the lower piston sleeve.

[0016] In some embodiments, the packer body further includes a lower connector, which is fixed to the lower end of the lower central tube and abuts against the lower telescopic body located at the lowest end.

[0017] In some embodiments, the compression mechanism further includes a ratchet locking ring, which is sleeved on the upper piston ring and built into the upper piston sleeve. The inner sidewall of the ratchet locking ring has a plurality of first ratchet teeth, the outer sidewall of the ratchet locking ring has a plurality of second ratchet teeth, the outer sidewall of the upper piston ring has a plurality of third ratchet teeth that cooperate with the first ratchet teeth, and the inner sidewall of the upper piston sleeve has a plurality of fourth ratchet teeth that cooperate with the second ratchet teeth.

[0018] Compared with existing technologies, the beneficial effects of the technical solution proposed in this invention are as follows: In use, the upper end of the central tube is connected to the tubing, and the lower end of the central tube is connected to a sealing ball seat. After the packer is lowered into the well to a predetermined position along with the tubing, a ball is dropped from the tubing port onto the sealing ball seat at the bottom of the packer, thereby sealing the sealing ball seat. Then, high-pressure liquid is pumped into the tubing, enters the central tube, and then enters the first injection chamber through the first unloading port. The lower piston ring and lower piston sleeve begin to bear force. When the force reaches the starting pressure of the lower piston ring and lower piston sleeve, the lower piston ring and lower piston sleeve are pushed to move in opposite directions, thereby pushing the two rubber sleeve assemblies respectively. The two rubber sleeve assemblies expand under pressure and press tightly against the casing, achieving the purpose of sealing. Because this invention adopts a double rubber sleeve design, the length of the sealing section can be greatly increased, and even in the event of a long fracture section, a sealing effect can be achieved, meeting the requirements of ultra-deep, ultra-high temperature, and ultra-high pressure wells. Attached Figure Description

[0019] Figure 1 This is a half-sectional view of an embodiment of the dual-tube naked-eye packer provided by the present invention when the tube assembly is not expanded;

[0020] Figure 2 yes Figure 1 A half-sectional view of the double-tube naked-eye packer after the expansion of the tube assembly;

[0021] Figure 3 yes Figure 2 A magnified view of a portion of region A in the middle;

[0022] Figure 4 yes Figure 2 A magnified view of a portion of region B in the middle;

[0023] In the diagram: 1-Packard body, 11-Central tube, 111-Upper central tube, 112-Lower central tube, 113-Second fixing screw, 11a-First oil drain hole, 11b-Second oil drain hole, 12-Upper connector, 13-Lower connector, 2-Extrusion mechanism, 21-Lower piston ring, 22-Lower piston sleeve, 22a-First oil injection chamber, 23-Upper piston ring, 24-Upper piston sleeve, 241-Second oil injection chamber, 25-First fixing screw, 26-First shearing pin, 27-Ratchet locking ring, 3-Expansion mechanism, 31-Glue tube assembly, 311-Upper glue tube assembly, 3111-Upper spacer ring, 3112-Upper telescopic body, 3113-Guide ring, 3114-Second shearing pin, 312-Lower glue tube assembly, 3121-Lower spacer ring, 3122-Lower telescopic body. Detailed Implementation

[0024] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0025] Please refer to Figures 1-3 The present invention provides a double-tube naked eye packer, including a packer body 1, a compression mechanism 2 and an expansion mechanism 3. The packer body 1 includes a central tube 11, and a first oil discharge hole 11a is provided on the side wall of the central tube 11.

[0026] The extrusion mechanism 2 includes a lower piston ring 21 and a lower piston sleeve 22. The lower piston ring 21 is slidably sleeved on the central tube 11. One end of the lower piston sleeve 22 is slidably and sealingly sleeved on the lower piston ring 21, and the other end is slidably and sealingly sleeved on the central tube 11. A first oil injection chamber 22a is formed between the lower piston ring 21 and the lower piston sleeve 22, which communicates with the first oil drain hole 11a.

[0027] The expansion mechanism 3 includes two rubber cylinder assemblies 31, which are respectively installed at both ends of the central tube 11 and connected to the lower piston ring 21 and the lower piston sleeve 22.

[0028] In use, the upper end of the central tube 11 is connected to the tubing, and the lower end of the central tube 11 is connected to a sealing ball seat. After the packer is lowered into the well to a predetermined position along with the tubing, a ball is dropped from the tubing port onto the sealing ball seat at the bottom of the packer, thereby sealing the sealing ball seat. Then, high-pressure fluid is pumped into the tubing, enters the central tube 11, and then enters the first injection chamber 22a through the first unloading port 11a. The lower piston ring 21 and the lower piston sleeve 22 begin to bear force. When the force reaches the starting pressure of the lower piston ring 21 and the lower piston sleeve 22, the lower piston ring 21 and the lower piston sleeve 22 are pushed to move in opposite directions, thereby pushing the two rubber sleeve assemblies 31 respectively. The two rubber sleeve assemblies 31 expand under pressure and press tightly against the casing, achieving the purpose of sealing. Because this invention adopts a double rubber sleeve design, the length of the sealing section can be greatly increased, and even in the event of a long fracture section, a sealing effect can be achieved, which can meet the requirements of ultra-deep, ultra-high temperature, and ultra-high pressure wells.

[0029] To improve the extrusion effect, please refer to Figures 1-3 In a preferred embodiment, a second oil drain hole 11b is also provided on the side wall of the central tube 11. The extrusion mechanism 2 further includes an upper piston ring 23 and an upper piston sleeve 24. The upper piston ring 23 is slidably sleeved on the central tube 11 and fixedly connected to the lower piston ring 21. One end of the upper piston sleeve 24 is slidably sleeved on the lower piston ring 21, and the other end of the upper piston sleeve 24 is slidably sleeved on the upper piston ring 23. The upper piston sleeve 24 is threadedly fixedly connected to the lower piston sleeve 22. A second oil injection chamber 241 communicating with the second oil drain hole 11b is formed between the upper piston ring 23 and the upper piston sleeve 24. When in use, high-pressure liquid enters the central tube 11, then enters the first oil filling chamber 22a through the first oil discharge hole 11a, and enters the second oil filling chamber 241 through the second oil discharge hole 11b. The lower piston ring 21, lower piston sleeve 22, upper piston ring 23 and upper piston sleeve 24 begin to be stressed. After reaching a certain starting pressure, they move in the opposite direction and squeeze the two rubber cylinder assemblies 31.

[0030] To achieve a secure connection between the upper piston sleeve 24 and the lower piston sleeve 22, please refer to... Figures 1-3 In a preferred embodiment, the upper piston sleeve 24 is threadedly fixed to the lower piston sleeve 22 and is fixedly connected via a plurality of first fixing screws 25.

[0031] To maintain stability in the initial state, please refer to Figures 1-3 In a preferred embodiment, the upper piston ring 23 and the upper piston sleeve 24 are fixedly connected by a plurality of first shear pins 26.

[0032] For easier assembly, please refer to... Figures 1-3In a preferred embodiment, the central tube 11 includes an upper central tube 111 and a lower central tube 112 coaxially fixedly connected. The two rubber sleeve assemblies are an upper rubber sleeve assembly 311 and a lower rubber sleeve assembly 312, respectively, which are installed on the upper central tube 111 and the lower central tube 112. In this embodiment, the upper central tube 111 and the lower central tube 112 are threaded together and locked by a plurality of second fixing screws 113. Preferably, the lower central tube 112 is sleeved outside the upper central tube 111, and the end face of the lower central tube 112 can abut against the lower piston ring 21. Thus, when encountering irregular well walls or foreign objects, the resistance can be transmitted to the lower central tube 112 and the upper central tube 111, and then to the tubing. Since the tubing has a resistance tonnage indicator, it can prevent midway obstruction and facilitate lowering.

[0033] To understand the specific functions of the glue applicator assembly 311, please refer to [link / reference]. Figures 1-3 In a preferred embodiment, the upper rubber sleeve assembly 311 includes a plurality of upper spacer rings 3111 and a plurality of upper telescopic bodies 3112. The upper spacer rings 3111 and the upper telescopic bodies 3112 are arranged alternately. Each upper telescopic body 3112 is movably connected to the adjacent upper spacer ring 3111. The lowermost upper telescopic body 3112 is fixedly connected to the upper piston ring 23. When compressed, the upper spacer rings 3111 move closer to each other, thereby squeezing each upper telescopic body 3112 and causing each upper telescopic body 3112 to expand. By setting the upper spacer rings 3111, the uniformity of the expansion of each upper telescopic body 3112 can be ensured.

[0034] To specifically achieve the fixed connection between the upper telescopic body 3112 and the upper piston ring 23, please refer to... Figures 1-3 In a preferred embodiment, the upper glue tube assembly 311 further includes a guide ring 3113, which is slidably sleeved on the upper central tube 111. One end of the guide ring 3113 is fixedly connected to the lowermost upper telescopic body 3112, and the other end of the guide ring 3113 is fixedly connected to the upper piston ring 23. The guide ring 3113 is fixedly connected to the upper central tube 111 via a plurality of second shear pins 3114. The packer body 1 further includes an upper connector 12, which is fixed to the upper end of the upper central tube 111 and abuts against the uppermost upper telescopic body 3112.

[0035] To understand the specific functions of the lower glue cartridge assembly 312, please refer to... Figures 1-3In a preferred embodiment, the lower rubber sleeve assembly 312 includes a plurality of lower partition rings 3121 and a plurality of lower telescopic bodies 3122. The lower partition rings 3121 and the lower telescopic bodies 3122 are arranged alternately. Each lower telescopic body 3122 is movably connected to the adjacent lower partition ring 3121. The uppermost lower telescopic body 3122 is fixedly connected to the lower piston sleeve 22. When compressed, the lower partition rings 3121 move closer to each other, thereby squeezing each lower telescopic body 3122 and causing each lower telescopic body 3122 to expand. By setting the lower partition rings 3121, the uniformity of the expansion of each lower telescopic body 3122 can be ensured.

[0036] For specific instructions on installing the central tube 112, please refer to... Figures 1-3 In a preferred embodiment, the packer body 1 further includes a lower connector 13, which is fixed to the lower end of the lower central tube 112 and abuts against the lower telescopic body 3122 located at the lowest end.

[0037] To maintain the sealing force, please refer to... Figures 1-4 In a preferred embodiment, the extrusion mechanism 2 further includes a ratchet locking ring 27, which is sleeved on the upper piston ring 23 and built into the upper piston sleeve 24. The inner sidewall of the ratchet locking ring 27 has a plurality of first ratchet teeth, the outer sidewall of the ratchet locking ring 27 has a plurality of second ratchet teeth, the outer sidewall of the upper piston ring 23 has a plurality of third ratchet teeth that cooperate with the first ratchet teeth, and the inner sidewall of the upper piston sleeve 24 has a plurality of fourth ratchet teeth that cooperate with the second ratchet teeth. The cooperation between the first and third ratchet teeth and the cooperation between the second and fourth ratchet teeth allows the upper piston ring 23 to move only away from the upper piston sleeve 24, thereby maintaining the sealing force and ensuring the sealing and anchoring effect.

[0038] It should be understood that the present invention also includes structures such as sealing rings and back rings to improve sealing performance. In addition, the prior art is not described in detail in the present invention.

[0039] To better understand this invention, the following is combined with... Figures 1-4The working process of the double-rubber sleeve open-hole packer provided by the present invention will be described in detail below: In use, the upper end of the central tube 11 is connected to the tubing, and the lower end of the central tube 11 is connected to a sealing ball seat. After the packer is lowered into the well to a predetermined position along with the tubing, a ball is dropped from the tubing port into the sealing ball seat at the bottom of the packer, thereby sealing the sealing ball seat. Then, high-pressure liquid is pumped into the tubing. The high-pressure liquid enters the central tube 11, and then enters the first injection chamber 22a through the first discharge port 11a, and exits through the second discharge port 11a. When piston b enters the second injection chamber 241, the lower piston ring 21, lower piston sleeve 22, upper piston ring 23, and upper piston sleeve 24 begin to bear force. After reaching a certain starting pressure, the first shear pin 26 and the second shear pin 3114 are cut off, and the lower piston ring 21 and the lower piston sleeve 22 are pushed to move in the opposite direction. At the same time, the upper piston ring 23 and the upper piston sleeve 24 also move in the same direction, thereby pushing the two rubber sleeve assemblies 31 respectively. The two rubber sleeve assemblies 31 expand under pressure and stick tightly to the casing, achieving the purpose of sealing. Because the present invention adopts a double rubber sleeve design, the length of the sealing section can be greatly increased. Even when encountering long fracture sections, a sealing effect can be achieved, which can meet the requirements of ultra-deep, ultra-high temperature, and ultra-high pressure wells.

[0040] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A double-tube open-eye packer, comprising a packer body, the packer body including a central tube, wherein a first oil discharge hole is formed on the side wall of the central tube, characterized in that, The dual-tube naked-eye packer also includes a compression mechanism and an expansion mechanism; The extrusion mechanism includes a lower piston ring and a lower piston sleeve. The lower piston ring is slidably sleeved on the central tube. One end of the lower piston sleeve is slidably and sealingly sleeved on the lower piston ring, and the other end is slidably and sealingly sleeved on the central tube. A first oil injection chamber communicating with the first oil discharge hole is formed between the lower piston ring and the lower piston sleeve. The expansion mechanism includes two rubber cylinder assemblies, which are respectively installed at both ends of the central tube and respectively connected to the lower piston ring and the lower piston sleeve; The side wall of the central tube is also provided with a second oil discharge hole. The extrusion mechanism also includes an upper piston ring and an upper piston sleeve. The upper piston ring is slidably sleeved on the central tube and fixedly connected to the lower piston ring. One end of the upper piston sleeve is slidably sleeved on the lower piston ring, and the other end of the upper piston sleeve is slidably sleeved on the upper piston ring. The upper piston sleeve and the lower piston sleeve are threadedly fixedly connected. A second oil injection chamber communicating with the second oil discharge hole is formed between the upper piston ring and the upper piston sleeve. The central tube includes an upper central tube and a lower central tube that are coaxially and fixedly connected. The two rubber sleeve assemblies are an upper rubber sleeve assembly and a lower rubber sleeve assembly, respectively, and the upper rubber sleeve assembly and the lower rubber sleeve assembly are respectively installed on the upper central tube and the lower central tube. The upper rubber sleeve assembly includes several upper spacer rings and several upper telescopic bodies. The upper spacer rings and the upper telescopic bodies are arranged alternately. Each upper telescopic body is movably connected to the adjacent upper spacer ring. The upper telescopic body located at the lowest end is fixedly connected to the upper piston ring. The upper rubber sleeve assembly also includes a guide ring, which is slidably sleeved on the upper central tube. One end of the guide ring is fixedly connected to the lowermost upper telescopic body, and the other end of the guide ring is fixedly connected to the upper piston ring. The guide ring is fixedly connected to the upper central tube via a plurality of second shear pins. The packer body also includes an upper connector, which is fixed to the upper end of the upper central tube and abuts against the upper telescopic body located at the uppermost end; The lower rubber sleeve assembly includes several lower partition rings and several lower telescopic bodies. The lower partition rings and the lower telescopic bodies are arranged alternately. Each lower telescopic body is movably connected to the adjacent lower partition ring. The uppermost lower telescopic body is fixedly connected to the lower piston sleeve.

2. The double-tube open-eye packer according to claim 1, characterized in that, The upper piston sleeve and the lower piston sleeve are threadedly fixedly connected and fixedly connected by a number of first fixing screws.

3. The double-tube open-eye packer according to claim 1, characterized in that, The upper piston ring and the upper piston sleeve are fixedly connected by a first shear pin.

4. The double-tube open-eye packer according to claim 1, characterized in that, The packer body also includes a lower connector, which is fixed to the lower end of the lower central tube and abuts against the lower telescopic body located at the lowest end.

5. The double-tube open-eye packer according to claim 1, characterized in that, The extrusion mechanism further includes a ratchet locking ring, which is sleeved on the upper piston ring and built into the upper piston sleeve. The inner sidewall of the ratchet locking ring has a plurality of first ratchet teeth, the outer sidewall of the ratchet locking ring has a plurality of second ratchet teeth, the outer sidewall of the upper piston ring has a plurality of third ratchet teeth that cooperate with the first ratchet teeth, and the inner sidewall of the upper piston sleeve has a plurality of fourth ratchet teeth that cooperate with the second ratchet teeth.

Images