High-temperature resistant super-high pressure cross-connection packer

Abstract

The application discloses a high-temperature-resistant and super-high-pressure cross-connection type packer and belongs to the field of oil and natural gas. The packer comprises a push-pull rod, a high-pressure waterway conversion component, upper and lower steel wire packers arranged at intervals along an axial direction, a jetting nipple and a pressure sensor assembly. The steel wire packer comprises inner and outer rubber cylinders and a steel wire assembly; the steel wire assembly which is wound in multiple layers and crosses each other forms a pressure-bearing reinforced structure with the rubber cylinder, and provides rebound force after pressure relief, so that the pressure-bearing capacity and unsealing performance of the packer are improved. The high-pressure waterway conversion component is switched between a packer inflation waterway and a fracturing waterway through axial movement of the push-pull rod; the inflation waterway is communicated with expansion cavities of the upper and lower steel wire packers respectively, and the fracturing waterway is communicated with a jetting hole of the jetting nipple. The two waterways are isolated by a sealing structure, and the two pressure sensor assemblies measure packer inflation pressure and fracturing pressure respectively. The application can realize setting, fracturing and pressure monitoring, and is suitable for segmented fracturing and ground stress detection of high-temperature and high-pressure wells.

Description

Technical Field

[0001] This invention relates to a high-temperature and ultra-high-pressure bridging packer, belonging to the field of petroleum and natural gas. Technical Background

[0002] In deep and ultra-deep well oil and gas exploration and development, as well as in-situ stress detection in deep well formations, the wellbore is typically exposed to high temperature, high pressure, and alternating pressure environments. Hydraulic fracturing stress measurement requires the use of two packers to isolate the test section before injecting high-pressure fluid into it to obtain parameters such as formation fracturing pressure and reopening pressure. Therefore, the packer's setting reliability, pressure-bearing capacity, unsealing performance, and the accuracy of pressure measurement in the test section directly affect the fracturing operation and in-situ stress testing results.

[0003] Existing deep stress measurement tools typically employ a push-pull high-pressure water circuit switching structure. This involves axially moving the valve core via the tubing or drill pipe to switch between the packer inflation water circuit and the test section fracturing water circuit. Existing packers and pressure monitoring devices also measure packer inflation pressure and test section fracturing pressure using independent pressure measurement components on both sides of the test section. These structures can meet the requirements for setting, fracturing, and pressure monitoring in conventional hydraulic fracturing processes. However, under the high temperature and high pressure conditions of ultra-deep wells, existing technologies still have the following shortcomings: First, conventional packers suffer from low pressure-bearing capacity and difficulty in unsealing; second, the upper and lower packers, fracturing water circuit, packer inflation water circuit, and pressure monitoring components need to be arranged within limited downhole tool space, resulting in numerous water circuit intersections and component connections, which can easily lead to water circuit crosstalk, seal failure, and mutual interference in pressure measurements.

[0004] Therefore, it is necessary to provide a bridging packer suitable for high-temperature and high-pressure deep well conditions. This packer should not only ensure reliable setting of the upper and lower packers and switching of the fracturing water circuit, but also improve the packer's pressure-bearing and unsealing performance. Furthermore, it should enable independent measurement of the packer's inflation pressure and fracturing pressure to meet the integrated operation requirements of deep well segmented fracturing and in-situ stress detection. Summary of the Invention

[0005] To achieve the above objectives, the technical solution adopted by the present invention to solve this problem is: a high-temperature and ultra-high-pressure bridging packer, comprising a push-pull rod, a high-pressure water circuit conversion component, an upper connector, an upper central tube, an upper wire packer, an upper adapter, a central tube extension connector, a jet short section, a lower adapter, a fracturing pressure bearing cylinder, a pressure sensor assembly A, a sensor connector A, an expansion pressure bearing cylinder, a pressure sensor assembly B, a sensor connector B, an adapter, a lower central tube, a lower wire packer, a sliding connector, and a guide connector.

[0006] The upper and lower wire packers are spaced apart along the tool's axial direction and have identical structures, each including an upper retaining ring, an inner rubber cylinder, a wire assembly, an outer rubber cylinder, and a lower retaining ring. The wire assembly is positioned between the inner and outer rubber cylinders, with both ends fixed to the upper and lower retaining rings. The wire assembly comprises multiple layers of radially arranged, cross-wound wires, allowing the packer to expand radially under high-pressure fluid. After pressure relief, the elastic recovery of the wire and rubber assemblies facilitates release.

[0007] The high-pressure water circuit conversion component, in conjunction with the push-pull rod, forms a conversion chamber and is equipped with mutually isolated fracturing and expansion outlets. The push-pull rod can move axially relative to the high-pressure water circuit conversion component under the influence of the tubing string. When the push-pull rod is in the setting position, the high-pressure fluid is connected to the expansion outlet, and the fracturing outlet is shut off. When the push-pull rod is in the fracturing position, the high-pressure fluid is connected to the fracturing outlet, and the expansion outlet is shut off, thereby achieving the switching between the packer's expansion water circuit and fracturing water circuit.

[0008] The fracturing water circuit consists of the fracturing outlet, upper connector, upper central tube, central tube extension connector, and interconnected flow channels within the jet sub-section of the high-pressure water circuit conversion component. The fracturing water circuit is connected to the jet orifice of the jet sub-section. The packer inflation water circuit consists of the inflation outlet, upper connector, upper inflation annulus formed between the outer side of the upper central tube and the inner side of the rubber sleeve of the upper wire mesh packer, upper adapter, lower adapter, conversion connector, and lower inflation annulus formed between the outer side of the lower central tube and the inner side of the rubber sleeve of the lower wire mesh packer. The packer inflation water circuit is connected to the expansion chambers of both the upper and lower wire mesh packers. The fracturing water circuit and the packer inflation water circuit are isolated at each connection point by a sealing structure.

[0009] A first pressure measuring chamber is formed within the fracturing pressure bearing cylinder, and pressure sensor assembly A is disposed within the first pressure measuring chamber. The first pressure measuring chamber is connected to the fracturing water circuit through the first pressure inlet of sensor connector A. A second pressure measuring chamber is formed within the expansion pressure bearing cylinder, and pressure sensor assembly B is disposed within the second pressure measuring chamber. The second pressure measuring chamber is connected to the packer inflation water circuit through the second pressure inlet of sensor connector B. The first and second pressure measuring chambers are isolated from each other by the bearing cylinder, sensor connector, and sealing structure to achieve independent measurement of fracturing pressure and packer inflation pressure.

[0010] The sliding joint forms an axial sliding fit and dynamic seal with the lower central tube, which is used to compensate for the axial displacement generated during the setting and expansion of the upper and lower wire packers.

[0011] Compared with the prior art, the beneficial effects of this invention are: (1) This invention achieves the switching between the packer inflation water path and the fracturing water path through the axial cooperation of the push-pull rod and the high-pressure water path conversion component, so that the tool can complete the double packer setting, fracturing and unsealing operations in the same process. (2) The upper and lower wire packers adopt a structure of multi-layer wire components cross-woven and vulcanized with the inner and outer rubber cylinders, which can limit the excessive deformation of the rubber components under high temperature and high pressure conditions, and provide elastic recovery force after depressurization, reduce the difficulty of unsealing caused by rubber viscosity, and improve the dynamic unsealing capability. (3) This invention forms a test section between the double packers and sets up mutually isolated fracturing water path and packer inflation water path; pressure sensor component A and pressure sensor component B measure the fracturing pressure and setting pressure respectively, providing cross-installation conditions for segmented fracturing and downhole pressure monitoring in high temperature and high pressure deep well geostress detection. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the high-temperature and ultra-high-pressure bridging packer of the present invention; 1-Push-pull rod; 2-O-ring seal A; 3-High-pressure water circuit conversion component; 4-Sealing screw; 5-O-ring seal B; 6-Upper connector; 7-Upper center tube; 8-Upper wire packer; 9-Upper adapter; 10-Center tube extension connector; 11-Jet short section; 12-Lower adapter; 13-Fracturing pressure bearing cylinder; 14-Pressure sensor assembly A; 15-Sensor connector A; 16-Expansion pressure bearing cylinder; 17-Pressure sensor assembly B; 18-Sensor connector B; 19-Conversion connector; 20-O-ring seal C; 21-Lower center tube; 22-Lower wire packer; 23-Sliding joint; 24-Guide joint.

[0013] Figure 2 This is a schematic diagram of the wire packer structure of the present invention; 801-Upper guard band; 802-Inner rubber sleeve; 803-Steel wire assembly; 804-Outer rubber sleeve; 805-Lower guard band.

[0014] Figure 3 This is a schematic diagram of the steel wire assembly of the present invention; Figure 4 This is a schematic diagram showing the packer inflation water circuit connection when the high-pressure water circuit conversion component of the present invention is in the set position; Figure 5 This is a schematic diagram of the flow channel when the wire packer of the present invention is in the inflated state; Figure 6 This is a schematic diagram of the pressure measurement component and the pressure-inducing water circuit structure of the present invention; Figure 7 This is a schematic diagram of the flow channel when the wire packer of the present invention is in the inflated state; Figure 8This is a schematic diagram of the wire packer of the present invention in the setting state; Figure 9 This is a schematic diagram of the fracturing water circuit connection when the high-pressure water circuit conversion component of the present invention is in the fracturing position; Figure 10 This is a schematic diagram of the fracturing state after the bridging packer of the present invention has been set. Detailed Implementation Plan

[0015] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0016] The specific embodiments of the present invention described herein are for illustrative purposes only and should not be construed as limiting the invention in any way. Under the teachings of this invention, those skilled in the art can conceive of any possible variations based on the invention, all of which should be considered within the scope of the invention. It should be noted that when an element is referred to as being "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or there may be an intervening element. The terms "mounted," "connected," and "linked" should be interpreted broadly; for example, they can refer to mechanical or electrical connections, or internal communication between two elements, and can be direct or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible embodiments.

[0017] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0018] As shown in the attached drawings, the high-temperature and ultra-high pressure bridging packer includes a push-pull rod 1, an O-ring seal A2, a high-pressure water circuit conversion component 3, a sealing screw 4, an O-ring seal B5, an upper connector 6, an upper central tube 7, an upper wire packer 8, an upper adapter 9, a central tube extension connector 10, a jet short section 11, a lower adapter 12, a fracturing pressure bearing cylinder 13, a pressure sensor assembly A14, a sensor connector A15, an expansion pressure bearing cylinder 16, a pressure sensor assembly B17, a sensor connector B18, an adapter 19, an O-ring seal C20, a lower central tube 21, a lower wire packer 22, a sliding connector 23, and a guide connector 24.

[0019] The upper wire packer 8 and the lower wire packer 22 are spaced apart along the tool axis. They have the same structure, both including an upper guard 801, an inner rubber cylinder 802, a wire assembly 803, an outer rubber cylinder 804, and a lower guard 805. The wire assembly 803 is located between the inner rubber cylinder 802 and the outer rubber cylinder 804. The upper guard 801 and the lower guard 805 are respectively connected to the two ends of the inner rubber cylinder 802, the wire assembly 803, and the outer rubber cylinder 804, thus forming a wire packer structure that can expand radially and rebound.

[0020] In this embodiment, the wire assembly 803 comprises 4 to 10 layers of wire arranged radially, each layer consisting of cross-wound wires with a crossing angle of 15° to 30°. Both ends of the wire assembly 803 are fixed to the upper guard band 801 and the lower guard band 805 via a curing anchoring structure or a layer-by-layer welding structure to prevent the wire assembly 803 from being pulled out axially during the setting process. The inner rubber sleeve 802 is connected to the upper guard band 801 and the lower guard band 805 using a vulcanization bonding process or an extrusion process.

[0021] The high-pressure water circuit conversion component 3 is connected to the upper connector 6. The push-pull rod 1 passes through the high-pressure water circuit conversion component 3 and forms an axially movable fit with it. An O-ring A2 is installed in the sealing groove of the high-pressure water circuit conversion component 3 to achieve a dynamic seal between the push-pull rod 1 and the high-pressure water circuit conversion component 3. A sealing screw 4 is installed on the outside of the high-pressure water circuit conversion component 3 to seal the process holes formed during the processing of the high-pressure flow channel. O-rings B5 and C20 are installed at the connection points of the corresponding parts to isolate the fracturing water circuit and the packer inflation water circuit.

[0022] The upper end of the upper connector 6 is connected to the high-pressure water circuit conversion component 3, and the lower end is connected to the upper central pipe 7 and the upper retaining ring 801 of the upper wire packer 8, respectively. The lower end of the upper central pipe 7 is connected to the central pipe extension connector 10. The upper adapter 9 is connected between the lower retaining ring 805 of the upper wire packer 8 and the jet stub 11. The lower end of the jet stub 11 is connected to the fracturing pressure bearing cylinder 13 and the adapter 19, respectively. The lower adapter 12 is located between the jet stub 11 and the fracturing pressure bearing cylinder 13, forming a connecting channel for the packer inflation water circuit.

[0023] Sensor connector A15 connects between the fracturing pressure bearing cylinder 13 and the expansion pressure bearing cylinder 16, and sensor connector B18 connects to the lower end of the expansion pressure bearing cylinder 16. The lower end of the conversion connector 19 connects to the lower central tube 21 and the lower wire packer 22, respectively. The sliding connector 23 connects to the lower end of the lower wire packer 22 and forms an axial sliding fit and dynamic seal with the lower central tube 21. The guide connector 24 connects to the lower end of the lower central tube 21.

[0024] The high-pressure water circuit conversion component 3 includes a conversion chamber, a fracturing outlet, and an expansion outlet. The push-pull rod 1, driven by the tubing string, can move axially between the setting position and the fracturing position. When the push-pull rod 1 is in the setting position, high-pressure fluid enters the expansion outlet through the radial flow hole of the push-pull rod 1, and the fracturing outlet is sealed off by the sealing structure. When the push-pull rod 1 is in the fracturing position, high-pressure fluid enters the fracturing outlet through the radial flow hole of the push-pull rod 1, and the expansion outlet is sealed off by the sealing structure. In this embodiment, the effective push-pull stroke of the push-pull rod 1 between the setting position and the fracturing position is 25 cm to 50 cm.

[0025] The fracturing outlet forms a fracturing water path through interconnected channels within the upper connector 6, upper central tube 7, central tube extension connector 10, and jet sub 11. The downstream end of the fracturing water path connects to the jet orifice of the jet sub 11. The inflation outlet forms a packer inflation water path through the upper inflation annulus formed between the outer side of the upper central tube 7 and the inner side of the inner rubber sleeve 802 of the upper wire mesh packer 8, the upper adapter 9, lower adapter 12, and conversion connector 19, and the lower inflation annulus formed between the outer side of the lower central tube 21 and the inner side of the inner rubber sleeve of the lower wire mesh packer 22. The packer inflation water path connects to the expansion chambers of the upper wire mesh packer 8 and the lower wire mesh packer 22.

[0026] The fracturing water circuit and the packer inflation water circuit are isolated by a sealing structure at the connection points of the high-pressure water circuit conversion component 3, upper connector 6, upper adapter 9, lower adapter 12 and conversion connector 19 to prevent cross-contamination between the two water circuits.

[0027] A first pressure measuring chamber is formed within the fracturing pressure bearing cylinder 13, and a pressure sensor assembly A14 is installed within it. A sensor connector A15 has a first pressure inlet hole, through which the first pressure measuring chamber communicates with the fracturing water passage. A second pressure measuring chamber is formed within the expansion pressure bearing cylinder 16, and a pressure sensor assembly B17 is installed within it. A sensor connector B18 has a second pressure inlet hole, through which the second pressure measuring chamber communicates with the packer inflation water passage. The first and second pressure measuring chambers are isolated by a sealing structure consisting of the fracturing pressure bearing cylinder 13, sensor connector A15, expansion pressure bearing cylinder 16, sensor connector B18, and their connecting parts.

[0028] After the tool is lowered into the predetermined well section, the push-pull rod 1 is in the setting position. High-pressure fluid enters the expansion chambers of the upper wire packer 8 and the lower wire packer 22 through the packer expansion water passage. Under the action of fluid pressure, the wire assembly 803 expands radially, causing the inner rubber sleeve 802 and the outer rubber sleeve 804 to fit against the well wall, thus setting the upper wire packer 8 and the lower wire packer 22 in the wellbore, forming a test section between them. During the setting process, the lower clamp 805, upper adapter 9, jet sub 11, lower adapter 12, conversion joint 19, and sliding joint 23 form an axial compensation assembly, and generate axial displacement relative to the lower central tube 21 through the sliding joint 23.

[0029] After setting, the tubing string is lowered, moving the push-pull rod 1 to the fracturing position. High-pressure fluid enters the fracturing water circuit and flows to the jet section 11, then is ejected through the jet orifice to carry out the fracturing operation. Pressure sensor assembly A14 measures the fracturing water circuit pressure through the first pressure tap, and pressure sensor assembly B17 measures the packer inflation water circuit pressure through the second pressure tap.

[0030] After the fracturing operation is completed, the tubing string is lifted to return the push-pull rod 1 to its original position, and the pressure in the packer inflation water circuit is released. The upper wire packer 8 and the lower wire packer 22 are released under the elastic recovery action of the wire assembly 803 and the rubber assembly, completing the tool removal operation.

Claims

1. A high-temperature and ultra-high-pressure bridging packer, comprising a push-pull rod (1), an O-ring seal A (2), a high-pressure water circuit conversion component (3), a sealing screw (4), an O-ring seal B (5), an upper connector (6), an upper central tube (7), an upper wire packer (8), an upper adapter (9), a central tube extension connector (10), a jet short section (11), a lower adapter (12), a fracturing pressure bearing cylinder (13), a pressure sensor assembly A (14), a sensor connector A (15), an expansion pressure bearing cylinder (16), a pressure sensor assembly B (17), a sensor connector B (18), an adapter (19), an O-ring seal C (20), a lower central tube (21), a lower wire packer (22), a sliding connector (23), and a guide connector (24), characterized in that: The upper wire packer (8) and the lower wire packer (22) are spaced apart along the axial direction. The upper wire packer (8) and the lower wire packer (22) have the same structure, each including an upper guard band (801), an inner rubber cylinder (802), a wire assembly (803), an outer rubber cylinder (804), and a lower guard band (805). The wire assembly (803) is located between the inner rubber cylinder (802) and the outer rubber cylinder (804). The upper guard band (801) and the lower guard band (805) are respectively connected to the two ends of the inner rubber cylinder (802), the wire assembly (803), and the outer rubber cylinder (804). The high-pressure water circuit conversion component (3) has a conversion chamber that cooperates with the push-pull rod (1), a fracturing outlet, and an expansion outlet. The fracturing outlet and the expansion outlet are connected together. A sealing structure is provided between the liquid outlets; the push-pull rod (1) can move axially between the setting position and the fracturing position relative to the high-pressure water circuit conversion component (3); when the push-pull rod (1) is in the setting position, the liquid inlet of the high-pressure water circuit conversion component (3) is connected to the expansion outlet, and the fracturing outlet is blocked by the sealing structure; when the push-pull rod (1) is in the fracturing position, the liquid inlet of the high-pressure water circuit conversion component (3) is connected to the fracturing outlet, and the expansion outlet is blocked by the sealing structure; the fracturing outlet forms a fracturing water circuit by sequentially passing through the upper connector (6), the upper central tube (7), the central tube extension connector (10), and the jet short section (11) interconnected flow channels, and the downstream end of the fracturing water circuit is connected to the jet hole of the jet short section (11); the expansion outlet The packer inflation water path is formed by passing through the upper joint (6), the upper central tube (7) and the inner rubber sleeve (802) of the upper wire packer (8) in sequence, the upper adapter (9), the lower adapter (12), the conversion joint (19), and the lower central tube (21) and the inner rubber sleeve of the lower wire packer (22) in sequence; the packer inflation water path is connected to the expansion chambers of the upper wire packer (8) and the lower wire packer (22) respectively; the fracturing water path and the packer inflation water path are isolated by a sealing structure at the connection points of the high pressure water path conversion component (3), the upper joint (6), the upper adapter (9), the lower adapter (12) and the conversion joint (19); the fracturing pressure bearing A first pressure measuring chamber is formed inside the carrier cylinder (13), and a pressure sensor assembly A (14) is installed inside the first pressure measuring chamber. A sensor connector A (15) is provided with a first pressure inlet hole, and the first pressure measuring chamber is connected to the fracturing water circuit through the first pressure inlet hole. A second pressure measuring chamber is formed inside the expansion pressure carrier cylinder (16), and a pressure sensor assembly B (17) is installed inside the second pressure measuring chamber. A sensor connector B (18) is provided with a second pressure inlet hole, and the second pressure measuring chamber is connected to the packer inflation water circuit through the second pressure inlet hole. The first pressure measuring chamber and the second pressure measuring chamber are isolated by the sealing structure of the fracturing pressure carrier cylinder (13), sensor connector A (15), expansion pressure carrier cylinder (16), sensor connector B (18) and their connecting parts.The sliding joint (23) forms an axial sliding fit and dynamic seal with the lower central tube (21), and the guide joint (24) is connected to the lower end of the lower central tube (21); the tubing connected by the push-pull rod (1) lowers the high-temperature and ultra-high pressure bridging packer into the predetermined well section; when the push-pull rod (1) is in the setting position, the high-pressure fluid enters the packer inflation water path through the radial flow hole of the push-pull rod (1), and enters the expansion chambers of the upper wire packer (8) and the lower wire packer (22) respectively, so that the upper wire packer (8) and the lower wire packer (22) expand radially and are set in the wellbore, thereby forming a test section; After the fracturing is completed, the tubing string is lowered, causing the push-pull rod (1) to move to the fracturing position. High-pressure fluid enters the fracturing water circuit and flows to the jet sub (11), and is ejected through the jet orifice to carry out the fracturing operation. Pressure sensor assembly A (14) measures the fracturing water circuit pressure through the first pressure inlet, and pressure sensor assembly B (17) measures the packer inflation water circuit pressure through the second pressure inlet. After the fracturing operation is completed, the tubing string is lifted to return the push-pull rod (1) to its original position, and the packer inflation water circuit is depressurized. The upper wire packer (8) and the lower wire packer (22) are released under the elastic recovery action of the wire assembly (803) and the rubber assembly.

2. The high-temperature and ultra-high-pressure bridging packer according to claim 1, characterized in that: The push-pull rod (1) and the high-pressure water circuit conversion component (3) can complete the conversion from the sealing water circuit to the fracturing water circuit. The push-pull rod (1) has a push-pull stroke of 25cm to 50cm.

3. The high-temperature and ultra-high-pressure bridging packer according to claim 1, characterized in that: During the setting process of the upper wire packer (8) and the lower wire packer (22), the radial expansion of the wire assembly (803) will cause the lower guard band (805), the upper adapter (9), the jet short section (11), the lower adapter (12), the conversion joint (19), and the sliding joint (23) to slide axially together to complete axial compensation.

4. The high-temperature and ultra-high-pressure bridging packer according to claim 1, characterized in that: After the upper wire packer (8) and the lower wire packer (22) are set, they seal the wellbore and form a sealed annulus.

5. A high-temperature and ultra-high-pressure bridging packer according to claim 1, characterized in that: The two ends of the wire assembly (803) can be fixed by curing or layer-by-layer welding process to prevent the setting failure caused by the wire assembly (803) being pulled out during setting.

6. A high-temperature and ultra-high-pressure bridging packer according to claim 1, characterized in that: The steel wire assembly (803) has 4 to 10 radially stacked layers, which are tightly wound layer by layer. Each layer of steel wires crosses each other at an angle of 15° to 30°, ensuring that the steel wire assembly (803) has good pressure-bearing capacity and desealing capacity.

7. A high-temperature and ultra-high-pressure bridging packer according to claim 1, characterized in that: The inner rubber cylinder (802) is connected to the upper guard band (801) and the lower guard band (805) by vulcanization bonding or extrusion.

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