Hydraulic pulse tool, tubular column tool string and hydraulic perforation and fracturing combined operation method

Abstract

The invention relates to the field of hydraulic perforation and fracturing, and discloses a hydraulic pulse tool, a tubular column tool string and a hydraulic pulse perforation and fracturing combined operation method.The hydraulic pulse tool comprises a shell, an eccentric pipe (2), an impeller shaft (4) and a pulse impeller (3), and the impeller shaft (4) extends perpendicular to the central axis of the shell; the eccentric pipe (2) is provided with an eccentric hole eccentrically formed relative to the central axis of the shell, any two adjacent blades and the eccentric pipe (2) can define a fluid cavity communicated with the eccentric hole, and the volume of the fluid cavity changes along with rotation of the pulse impeller (3). According to the scheme, the continuous oil pipe hydraulic pulse perforation and fracturing combined process can be achieved, the continuous stress wave impact effect can be formed, the continuous oil pipe hydraulic jet perforation effect can be remarkably improved, rock fatigue damage can be promoted in the fracturing process, the crack initiation pressure can be reduced, and the fracturing effect can be comprehensively improved.

Description

Technical Field

[0001] The invention relates to the field of continuous tubing perforation and fracturing of oil and gas wells, and specifically to a hydraulic pulse tool, a tubing tool string, and a hydraulic pulse perforation and fracturing combined operation method. Background Art

[0002] At present, hydraulic pulse technology is mostly used in the field of oil and gas resource development, such as water injection, drag reduction and jet drilling. Hydraulic pulse fracturing technology is one of the hydraulic fracturing methods explored in the industry in recent years, and has achieved good application results in coal seam pulse fracturing pressure relief and permeability enhancement construction.

[0003] The continuous tubing perforation and fracturing of oil and gas wells is mainly achieved by pumping the perforating fluid carrying perforating sand into the internal channels of the continuous tubing and string tools by the ground pump truck and spraying it out through the nozzle of the hydraulic ejector to achieve hydraulic sandblasting perforation, and then pumping the fracturing fluid carrying proppant into the tubing or the annulus of the oil casing to carry out hydraulic fracturing construction. It is one of the main technologies for staged fracturing transformation of low permeability oil and gas fields. The continuous tubing bottom seal drag fracturing string usually consists of a continuous tubing connector, a one-way valve, a safety joint, a rigid centralizer, a hydraulic ejector, a bottom packer, a casing coupling positioner and a guide centralizer, and relies on the continuous tubing to be lowered into the wellbore of the oil and gas well for construction.

[0004] Due to the large scale and complex process of reservoir transformation in oil and gas fields, the working fluid carrying perforating sand and proppant has high requirements for flow channels, and it is difficult to directly apply hydraulic pulse technology to the continuous tubing perforation and fracturing of oil and gas wells. Its core technology is the downhole hydraulic pulse tool. Most of the downhole hydraulic pulse tools at home and abroad are normally closed radial injection structures. The tools cannot be backwashed or recoiled normally. There is a great construction risk in the combination with fracturing, and it is not suitable for volume fracturing of tight oil and gas reservoirs or continuous tubing fine segmentation hydraulic jet fracturing operations; in addition, the flow rate of the pulse tool is relatively small, which is not suitable for fracturing operations. Therefore, it is necessary to remove the pulse tool after the perforation process is completed before the fracturing process can be carried out. Summary of the invention

[0005] The purpose of the present invention is to overcome the problems of the hydraulic pulse tool in the prior art that it is not suitable for the joint operation of perforating and fracturing and has radial leakage.

[0006] In order to achieve the above-mentioned objectives, the present invention provides a hydraulic pulse tool on one hand, wherein the hydraulic pulse tool comprises a tubular shell, an eccentric tube arranged in the shell, an impeller shaft arranged downstream of the eccentric tube, and a pulse impeller having multiple blades rotatably arranged on the impeller shaft, wherein the impeller shaft extends perpendicular to the central axis of the shell, the eccentric tube has an eccentric hole eccentrically arranged relative to the central axis of the shell, any two adjacent blades can enclose a fluid cavity connected to the eccentric hole with the eccentric tube, and the volume of the fluid cavity changes with the rotation of the pulse impeller.

[0007] In some embodiments, the central axis of the impeller shaft and the central axis of the housing intersect each other, and the eccentric hole is disposed on one side of a plane passing through the central axis of the impeller shaft and the central axis of the housing.

[0008] In some embodiments, a hemispherical lower concave surface is formed at the downstream end of the eccentric tube, and the blades can be clearance-matched with the lower concave surface.

[0009] In some embodiments, a hemispherical upper concave surface is formed at the upstream end of the eccentric tube, and the eccentric hole is arranged at the upper concave surface.

[0010] In some embodiments, a gradually expanding portion transitionally connected to the upper recessed surface is provided in the shell.

[0011] In some embodiments, the hydraulic pulse tool includes a tubular support seat disposed downstream of the eccentric tube, the support seat having a through hole transitioning from the lower concave surface to the outlet of the housing.

[0012] In some embodiments, the through hole comprises a tapered hole, and a guide groove is disposed on an inner surface of the tapered hole.

[0013] In some embodiments, the housing includes an upper joint and a lower joint that are detachably connected to each other.

[0014] On the other hand, the present solution also provides a tubular tool string, characterized in that the tubular tool string includes an oil pipe, a hydraulic ejector connected to the oil pipe, and the hydraulic pulse tool described in the above solution, and the hydraulic pulse tool is arranged upstream of the hydraulic ejector.

[0015] In some embodiments, the tubing tool string includes a continuous tubing connector, a one-way valve, a safety joint, a rigid centralizer, a bottom packer, a casing coupling locator, and a guide centralizer, which are arranged in sequence from top to bottom, and the hydraulic ejector and the hydraulic pulse tool are arranged between the rigid centralizer and the bottom packer.

[0016] On the other hand, the present invention also provides a method for hydraulic pulse perforation and fracturing, comprising the following steps: Lowering the above-mentioned tubing tool string into the well so that the hydraulic ejector reaches the target reservoir; Setting the bottom packer; Conduct hydraulic pulse sandblasting perforation; Perform hydraulic fracturing.

[0017] In some embodiments, it further comprises: The tubing tool string is lifted so that the hydraulic ejector reaches other reservoirs, and after the bottom packer is set, hydraulic pulse sandblasting perforation and hydraulic fracturing are performed respectively.

[0018] Through the above technical scheme, the perforating fluid and fracturing fluid are pumped into the formation in the form of continuous pulse dynamic load through the tool, thereby generating alternating loads and forming a continuous stress wave impact effect; there is no radial leakage in the tool, which can significantly improve the hydraulic jet perforation effect of the coiled tubing; the tool flow channel is unobstructed and continuous, which can support backwashing and recoil during the construction process; relying on the hydraulic pulse effect in the fracturing stage can: ① promote rock fatigue damage and reduce the fracture initiation pressure; ② the alternating load creates favorable conditions for inducing the formation of a complex fracture network; ③ strengthen the fracturing fluid sand carrying and sand spreading in the fracture, which is beneficial to the fracture height control and comprehensively improves the fracturing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a cross-sectional view of a hydraulic pulse tool according to an embodiment of the present invention; Figure 2 It is a schematic diagram of the structure of the eccentric tube and the pulse impeller described in the implementation mode of this scheme; Figure 3 It is a schematic diagram of the structure of the tubular tool described in the implementation mode of this scheme.

[0020] Description of Reference Numerals 1 Upper joint 2 Eccentric tube 3 pulse impellers 4 impeller shafts 5 support seat 6 lower joint 7 Coiled tubing connector 8 Check valve 9 Safety joint 10 Rigid centralizer 11Hydraulic pulse tool 12Hydraulic ejector 13 bottom packer 14 casing coupling locator 15 Guide Centralizer DETAILED DESCRIPTION The following is a further detailed description of the embodiments of the present disclosure in conjunction with the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to exemplarily illustrate the principles of the present disclosure, but cannot be used to limit the scope of the present disclosure. The present disclosure can be implemented in many different forms and is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

[0021] The present disclosure provides these embodiments to make the present disclosure thorough and complete, and to fully express the scope of the present disclosure to those skilled in the art. It should be noted that unless otherwise specifically stated, the relative arrangement of the parts and steps, the composition of the materials, the numerical expressions and the numerical values ​​set forth in these embodiments should be interpreted as being merely exemplary, and not as limiting.

[0022] It should be noted that, in the description of the present disclosure, unless otherwise specified, the meaning of "multiple" is greater than or equal to two; the terms "upper", "lower", "left", "right", "inner", "outer", etc., indicating the orientation or positional relationship, are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present disclosure. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0023] In addition, the words "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different parts. "Vertical" does not mean vertical in the strict sense, but is within the tolerance range. "Parallel" does not mean parallel in the strict sense, but is within the tolerance range. "Include" or "comprising" and similar words mean that the elements before the word include the elements listed after the word, and do not exclude the possibility of including other elements.

[0024] It should also be noted that in the description of the present disclosure, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to the specific circumstances. When a specific device is described as being located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device.

[0025] All terms used in the present disclosure have the same meanings as those understood by those of ordinary skill in the art to which the present disclosure belongs, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries, for example, should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an idealized or extremely formal sense, unless explicitly defined as such herein.

[0026] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0027] Embodiment 1 refer to Figure 1 and Figure 2 As shown, the present scheme provides a hydraulic pulse tool, wherein the hydraulic pulse tool comprises a tubular shell, an eccentric tube 2 arranged in the shell, an impeller shaft 4 arranged downstream of the eccentric tube 2, and a pulse impeller 3 with multiple blades rotatably arranged on the impeller shaft 4, wherein the impeller shaft 4 extends perpendicular to the central axis of the shell, the eccentric tube 2 has an eccentric hole eccentrically arranged relative to the central axis of the shell, any two adjacent blades can enclose a fluid cavity connected to the eccentric hole with the eccentric tube 2, and the volume of the fluid cavity changes with the rotation of the pulse impeller 3.

[0028] The hydraulic pulse tool can be used in a continuous oil pipe and can convert the fluid passing through it into a pulsed fluid so as to perform a perforation and fracturing joint process through the pulsed fluid.

[0029] The shell can be used to be connected to an oil pipe to allow fluid to pass through. The eccentric tube 2 is provided with an eccentric hole so that the fluid can flow therethrough eccentrically relative to the central axis of the shell. The pulse impeller 3 is rotatably arranged on the impeller shaft 4. When the fluid passing through the eccentric tube 2 reaches the pulse impeller 3, it can act on its blades to drive the pulse impeller 3 to rotate.

[0030] The pulse impeller 3 includes multiple blades. When two adjacent blades rotate to the side facing the eccentric tube 2, they can form a fluid cavity connected to the eccentric hole with the eccentric tube 2. During the rotation, the fluid cavity changes from nothing to something and then to nothing, and its volume changes continuously, so that the flow rate of the fluid passing through the pulse impeller 3 also changes continuously, thereby forming a pulsed fluid.

[0031] In other words, the fluid passing through the eccentric tube 2 can act on the blades on one side of the pulse impeller 3, thereby driving the pulse impeller 3 to rotate continuously and periodically, and this periodic rotation in turn makes the fluid form a periodically changing fluid.

[0032] Among them, the ratio of the inner diameter of the eccentric hole in the eccentric tube 2 to the inner diameter of the eccentric tube 2 can be relatively large, that is, the inner diameter of the eccentric hole is larger, which can ensure that the flow through the eccentric hole is at a larger level. Therefore, the tool can not only be used for hydraulic perforating operations, but also for fracturing operations with large flow requirements.

[0033] In this scheme, the perforating fluid and fracturing fluid are pumped into the formation in the form of continuous pulse dynamic load through the tool, thereby generating alternating loads, which can form a continuous stress wave impact effect; there is no radial leakage in the tool, which can significantly improve the hydraulic jet perforation effect of the coiled tubing; during the fracturing stage, the hydraulic pulse effect can: ① promote rock fatigue damage and reduce the fracture initiation pressure; ② the alternating load creates favorable conditions for inducing the formation of complex fracture networks; ③ strengthen the fracturing fluid sand carrying and sand spreading in the fracture, which is beneficial to the fracture height control and comprehensively improves the fracturing effect.

[0034] In some embodiments, the central axis of the impeller shaft 4 and the central axis of the housing intersect each other, and the eccentric hole is arranged on one side of a plane passing through the central axis of the impeller shaft 4 and the central axis of the housing. Figure 1 As shown, the central axis of the impeller shaft 4 and the central axis of the casing intersect each other perpendicularly, and an eccentric hole is provided on the lower side of the plane passing through the two central axes. The fluid passing through the eccentric hole acts on the blades on the lower side of the pulse impeller 3, so that the pulse impeller 3 can rotate continuously, and the fluid is contained between two adjacent blades and flows periodically through the periodic rotation of the pulse impeller 3, forming a pulse fluid.

[0035] The eccentric hole may be tangent to a plane passing through the central axis of the impeller shaft 4 and the central axis of the housing, and the inner diameter of the eccentric hole is the same as the radius of the pulse impeller 3 .

[0036] refer to Figure 2 As shown, the eccentric hole is a circular hole, and can certainly be a semicircular hole, so that the cross section of the eccentric hole reaches half of the maximum flow area of ​​the eccentric tube 2, thereby maximizing the flow area of ​​the eccentric hole to be compatible with fracturing operations.

[0037] The pulse impeller 3 may have a plurality of blades evenly distributed in the circumferential direction, for example, three blades; of course, even if the plurality of blades are spaced at different angles in the circumferential direction, the pulse impeller 3 may also allow the fluid passing through to form a pulse fluid with periodically changing flow rate.

[0038] In some embodiments, a hemispherical lower concave surface is formed at the downstream end of the eccentric tube 2, and the blades can be fitted with the lower concave surface. The blades of the pulse impeller 3 have arc-shaped edges, and the arc-shaped edges of the multiple blades are in the same concentric spherical surface, the center of the spherical surface is the intersection of the central axis of the impeller shaft 4 and the central axis of the shell; and the center of the lower concave surface is also the intersection of the central axis of the impeller shaft 4 and the central axis of the shell, and the arc-shaped edge of the blade is fitted with the lower concave surface to allow the blade to slide relative to the lower concave surface.

[0039] In some embodiments, a hemispherical upper concave surface is formed at the upstream end of the eccentric tube 2, and the eccentric hole is arranged at the upper concave surface. The concave structure formed around the eccentric hole of the eccentric tube 2 can make the fluid transition through the smooth spherical surface when entering the eccentric hole, avoiding the turbulence of the fluid here and causing excessive scouring of the eccentric tube 2.

[0040] The above describes the structure of the eccentric tube 2, which can be roughly cylindrical as a whole, and spherical concave surfaces are formed at both ends, and then an eccentric hole is processed; the influence of the eccentric hole on the shape of the spherical concave surface is not considered, this is just for the convenience of description, and technical personnel in this field can understand the specific form of the concave surface.

[0041] In some embodiments, the housing is provided with a gradually expanding portion transitionally connected to the upper concave surface. Figure 1 As shown, the part of the shell body that contacts the upper concave surface is gradually expanded, so as to realize a smooth transition from the smaller inner diameter of the shell body to the larger inner diameter of the upper concave surface, and avoid the formation of turbulence and excessive scouring. The gradual expansion here refers to the gradual increase of the inner diameter along the flow direction of the fluid.

[0042] In addition, the hydraulic pulse tool includes a tubular support seat 5 disposed downstream of the eccentric tube 2, and the support seat 5 has a through hole transitioning from the lower concave surface to the outlet of the housing. The through hole of the support seat 5 allows fluid to pass through, and one end of the support seat 5 is connected to the eccentric tube 2, and the other end is connected to the outlet of the housing. Figure 1 It can be seen that the pulse impeller 3 is accommodated at the connection between the eccentric tube 2 and the support seat 5. The inner diameter of the outlet of the support seat 5 is smaller than its inner diameter of the inlet, and its inner diameter of the inlet needs to be connected with the inner diameter of the lower concave surface of the eccentric tube 2, but the flow of the fluid passing through the eccentric tube 2 is limited by the eccentric hole, and the inner diameter of the eccentric hole is only 1 / 2 or less of the lower concave surface. Therefore, the inner diameter of the outlet of the shell is relatively smaller to match the flow of the eccentric hole, and the inner diameter of the outlet of the support seat 5 is also correspondingly smaller.

[0043] Wherein, the through hole includes a tapered hole, and a guide groove is arranged on the inner surface of the tapered hole. The support seat 5 is provided with a tapered hole at its outlet end so that the inner diameter gradually transitions to a level matching the outlet inner diameter of the shell. The tapering here means that the inner diameter gradually decreases in the direction of fluid flow. The tapered portion can make the inner diameter decrease smoothly, avoiding or alleviating the turbulence of the fluid here and causing excessive scouring. In addition, the guide groove can guide the fluid to flow in a specific direction, avoiding the deposition of solid particles in the sand-containing perforating fluid at the tapered hole. A plurality of guide grooves, for example, 3, can be arranged at intervals in the circumferential direction.

[0044] In some embodiments, the housing includes an upper joint 1 and a lower joint 6 that are detachably connected to each other. The lower end of the upper joint 1 is inserted into the upper end of the lower joint 6, and the lower end of the upper joint 1 can form an external thread, and the upper end of the lower joint 6 can form an internal thread, so as to allow the upper joint 1 and the lower joint 6 to be threaded together, and a sealing ring can be provided between the upper joint 1 and the lower joint 6 to improve the sealing between the two and prevent the fluid from leaking outward. In addition, the upper joint 1 and the lower joint 6 can be connected to each other by bolts to prevent the two from accidentally disengaging.

[0045] Embodiment 2 refer to Figure 1 and Figure 2 As shown, the present scheme provides a hydraulic pulse tool, wherein the hydraulic pulse tool comprises a tubular shell, an eccentric tube 2 arranged in the shell, an impeller shaft 4 arranged downstream of the eccentric tube 2, and a pulse impeller 3 with multiple blades rotatably arranged on the impeller shaft 4, wherein the impeller shaft 4 extends perpendicular to the central axis of the shell, the eccentric tube 2 has an eccentric hole eccentrically arranged relative to the central axis of the shell, any two adjacent blades can enclose a fluid cavity connected to the eccentric hole with the eccentric tube 2, and the volume of the fluid cavity changes with the rotation of the pulse impeller 3.

[0046] The hydraulic pulse tool can be used in a coiled tubing to convert the fluid passing through into a pulsed fluid, so as to perform a perforation and fracturing joint process through the pulsed fluid.

[0047] The shell can be used to be connected to an oil pipe to allow fluid to pass through. The eccentric tube 2 is provided with an eccentric hole so that the fluid can flow therethrough eccentrically relative to the central axis of the shell. The pulse impeller 3 is rotatably arranged on the impeller shaft 4. When the fluid passing through the eccentric tube 2 reaches the pulse impeller 3, it can act on its blades to drive the pulse impeller 3 to rotate.

[0048] The pulse impeller 3 includes multiple blades. When two adjacent blades rotate to the side facing the eccentric tube 2, they can form a fluid cavity connected to the eccentric hole with the eccentric tube 2. During the rotation, the fluid cavity changes from nothing to something and then to nothing, and its volume changes continuously, so that the flow rate of the fluid passing through the pulse impeller 3 also changes continuously, thereby forming a pulsed fluid.

[0049] In other words, the fluid passing through the eccentric tube 2 can act on the blades on one side of the pulse impeller 3, thereby driving the pulse impeller 3 to rotate continuously and periodically, and this periodic rotation in turn makes the fluid form a periodically changing fluid.

[0050] Among them, the ratio of the inner diameter of the eccentric hole in the eccentric tube 2 to the inner diameter of the eccentric tube 2 can be relatively large, that is, the inner diameter of the eccentric hole is larger, which can ensure that the flow through the eccentric hole is at a larger level. Therefore, the tool can not only be used for hydraulic perforating operations, but also for fracturing operations with large flow requirements.

[0051] In this scheme, the perforating fluid and fracturing fluid are pumped into the formation in the form of continuous pulse dynamic load through the tool, thereby generating alternating loads, which can form a continuous stress wave impact effect; there is no radial leakage in the tool, which can significantly improve the hydraulic jet perforation effect of the coiled tubing; during the fracturing stage, the hydraulic pulse effect can: ① promote rock fatigue damage and reduce the fracture initiation pressure; ② the alternating load creates favorable conditions for inducing the formation of complex fracture networks; ③ strengthen the fracturing fluid sand carrying and sand spreading in the fracture, which is beneficial to the fracture height control and comprehensively improves the fracturing effect.

[0052] In some embodiments, the central axis of the impeller shaft 4 and the central axis of the housing intersect each other, and the eccentric hole is arranged on one side of a plane passing through the central axis of the impeller shaft 4 and the central axis of the housing. Figure 1 As shown, the central axis of the impeller shaft 4 and the central axis of the casing intersect each other perpendicularly, and an eccentric hole is provided on the lower side of the plane passing through the two central axes. The fluid passing through the eccentric hole acts on the blades on the lower side of the pulse impeller 3, so that the pulse impeller 3 can rotate continuously, and the fluid is contained between two adjacent blades and flows periodically through the periodic rotation of the pulse impeller 3, forming a pulse fluid.

[0053] The eccentric hole may be tangent to a plane passing through the central axis of the impeller shaft 4 and the central axis of the housing, and the inner diameter of the eccentric hole is the same as the radius of the pulse impeller 3 .

[0054] refer to Figure 2 As shown, the eccentric hole is a circular hole, and can certainly be a semicircular hole, so that the cross section of the eccentric hole reaches half of the maximum flow area of ​​the eccentric tube 2, thereby maximizing the flow area of ​​the eccentric hole to be compatible with fracturing operations.

[0055] The pulse impeller 3 may have a plurality of blades evenly distributed in the circumferential direction, for example, four blades; of course, even if the plurality of blades are spaced at different angles in the circumferential direction, the pulse impeller 3 may also allow the fluid passing through to form a pulse fluid with periodically changing flow rate.

[0056] In some embodiments, a hemispherical lower concave surface is formed at the downstream end of the eccentric tube 2, and the blades can be fitted with the lower concave surface. The blades of the pulse impeller 3 have arc-shaped edges, and the arc-shaped edges of the multiple blades are in the same concentric spherical surface, the center of the spherical surface is the intersection of the central axis of the impeller shaft 4 and the central axis of the shell; and the center of the lower concave surface is also the intersection of the central axis of the impeller shaft 4 and the central axis of the shell, and the arc-shaped edge of the blade is fitted with the lower concave surface to allow the blade to slide relative to the lower concave surface.

[0057] In some embodiments, a hemispherical upper concave surface is formed at the upstream end of the eccentric tube 2, and the eccentric hole is arranged at the upper concave surface. The concave structure formed around the eccentric hole of the eccentric tube 2 can make the fluid transition through the smooth spherical surface when entering the eccentric hole, avoiding the turbulence of the fluid here and causing excessive scouring of the eccentric tube 2.

[0058] The above describes the structure of the eccentric tube 2, which can be roughly cylindrical as a whole, and spherical concave surfaces are formed at both ends, and then an eccentric hole is processed; the influence of the eccentric hole on the shape of the spherical concave surface is not considered, this is just for the convenience of description, and technical personnel in this field can understand the specific form of the concave surface.

[0059] In some embodiments, the housing is provided with a gradually expanding portion transitionally connected to the upper concave surface. Figure 1 As shown, the part of the shell body that contacts the upper concave surface is gradually expanded, so as to realize a smooth transition from the smaller inner diameter of the shell body to the larger inner diameter of the upper concave surface, and avoid the formation of turbulence and excessive scouring. The gradual expansion here refers to the gradual increase of the inner diameter along the flow direction of the fluid.

[0060] In addition, the hydraulic pulse tool includes a tubular support seat 5 disposed downstream of the eccentric tube 2, and the support seat 5 has a through hole transitioning from the lower concave surface to the outlet of the housing. The through hole of the support seat 5 allows fluid to pass through, and one end of the support seat 5 is connected to the eccentric tube 2, and the other end is connected to the outlet of the housing. Figure 1It can be seen that the pulse impeller 3 is accommodated at the connection between the eccentric tube 2 and the support seat 5. The inner diameter of the outlet of the support seat 5 is smaller than its inner diameter of the inlet, and its inner diameter of the inlet needs to be connected with the inner diameter of the lower concave surface of the eccentric tube 2, but the flow of the fluid passing through the eccentric tube 2 is limited by the eccentric hole, and the inner diameter of the eccentric hole is only 1 / 2 or less of the lower concave surface. Therefore, the inner diameter of the outlet of the shell is relatively smaller to match the flow of the eccentric hole, and the inner diameter of the outlet of the support seat 5 is also correspondingly smaller.

[0061] Wherein, the through hole includes a tapered hole, and a guide groove is arranged on the inner surface of the tapered hole. The support seat 5 is provided with a tapered hole at its outlet end so that the inner diameter gradually transitions to a level matching the outlet inner diameter of the shell. The tapering here means that the inner diameter gradually decreases in the direction of fluid flow. The tapered portion can make the inner diameter decrease smoothly, avoiding or alleviating the turbulence of the fluid here and causing excessive scouring. In addition, the guide groove can guide the fluid to flow in a specific direction, avoiding the deposition of solid particles in the sand-containing perforating fluid at the tapered hole. A plurality of guide grooves, for example, 4, can be arranged at intervals in the circumferential direction.

[0062] In some embodiments, the housing includes an upper joint 1 and a lower joint 6 that are detachably connected to each other. The lower end of the upper joint 1 is inserted into the upper end of the lower joint 6, and the lower end of the upper joint 1 can form an external thread, and the upper end of the lower joint 6 can form an internal thread, so as to allow the upper joint 1 and the lower joint 6 to be threaded together, and a sealing ring can be provided between the upper joint 1 and the lower joint 6 to improve the sealing between the two and prevent the fluid from leaking outward. In addition, the upper joint 1 and the lower joint 6 can be connected to each other by bolts to prevent the two from accidentally disengaging.

[0063] Embodiment 3 refer to Figure 1 and Figure 2 As shown, the present scheme provides a hydraulic pulse tool, wherein the hydraulic pulse tool comprises a tubular shell, an eccentric tube 2 arranged in the shell, an impeller shaft 4 arranged downstream of the eccentric tube 2, and a pulse impeller 3 with multiple blades rotatably arranged on the impeller shaft 4, wherein the impeller shaft 4 extends perpendicular to the central axis of the shell, the eccentric tube 2 has an eccentric hole eccentrically arranged relative to the central axis of the shell, any two adjacent blades can enclose a fluid cavity connected to the eccentric hole with the eccentric tube 2, and the volume of the fluid cavity changes with the rotation of the pulse impeller 3.

[0064] The hydraulic pulse tool can be used in a continuous oil pipe and can convert the fluid passing through it into a pulsed fluid so as to perform a perforation and fracturing joint process through the pulsed fluid.

[0065] The shell can be used to be connected to an oil pipe to allow fluid to pass through. The eccentric tube 2 is provided with an eccentric hole so that the fluid can flow therethrough eccentrically relative to the central axis of the shell. The pulse impeller 3 is rotatably arranged on the impeller shaft 4. When the fluid passing through the eccentric tube 2 reaches the pulse impeller 3, it can act on its blades to drive the pulse impeller 3 to rotate.

[0066] The pulse impeller 3 includes multiple blades. When two adjacent blades rotate to the side facing the eccentric tube 2, they can form a fluid cavity connected to the eccentric hole with the eccentric tube 2. During the rotation, the fluid cavity changes from nothing to something and then to nothing, and its volume changes continuously, so that the flow rate of the fluid passing through the pulse impeller 3 also changes continuously, thereby forming a pulsed fluid.

[0067] In other words, the fluid passing through the eccentric tube 2 can act on the blades on one side of the pulse impeller 3, thereby driving the pulse impeller 3 to rotate continuously and periodically, and this periodic rotation in turn makes the fluid form a periodically changing fluid.

[0068] Among them, the ratio of the inner diameter of the eccentric hole in the eccentric tube 2 to the inner diameter of the eccentric tube 2 can be relatively large, that is, the inner diameter of the eccentric hole is larger, which can ensure that the flow through the eccentric hole is at a larger level. Therefore, the tool can not only be used for hydraulic perforating operations, but also for fracturing operations with large flow requirements.

[0069] In this scheme, the perforating fluid and fracturing fluid are pumped into the formation in the form of continuous pulse dynamic load through the tool, thereby generating alternating loads, which can form a continuous stress wave impact effect; there is no radial leakage in the tool, which can significantly improve the hydraulic jet perforation effect of the coiled tubing; during the fracturing stage, the hydraulic pulse effect can: ① promote rock fatigue damage and reduce the fracture initiation pressure; ② the alternating load creates favorable conditions for inducing the formation of complex fracture networks; ③ strengthen the fracturing fluid sand carrying and sand spreading in the fracture, which is beneficial to the fracture height control and comprehensively improves the fracturing effect.

[0070] In some embodiments, the central axis of the impeller shaft 4 and the central axis of the housing intersect each other, and the eccentric hole is arranged on one side of a plane passing through the central axis of the impeller shaft 4 and the central axis of the housing. Figure 1 As shown, the central axis of the impeller shaft 4 and the central axis of the casing intersect each other perpendicularly, and an eccentric hole is provided on the lower side of the plane passing through the two central axes. The fluid passing through the eccentric hole acts on the blades on the lower side of the pulse impeller 3, so that the pulse impeller 3 can rotate continuously, and the fluid is contained between two adjacent blades and flows periodically through the periodic rotation of the pulse impeller 3, forming a pulse fluid.

[0071] The eccentric hole may be tangent to a plane passing through the central axis of the impeller shaft 4 and the central axis of the housing, and the inner diameter of the eccentric hole is the same as the radius of the pulse impeller 3 .

[0072] refer to Figure 2 As shown, the eccentric hole is a circular hole, and can certainly be a semicircular hole, so that the cross section of the eccentric hole reaches half of the maximum flow area of ​​the eccentric tube 2, thereby maximizing the flow area of ​​the eccentric hole to be compatible with fracturing operations.

[0073] The pulse impeller 3 may have a plurality of blades evenly distributed in the circumferential direction, for example, 5 blades; of course, even if the plurality of blades are spaced at different angles in the circumferential direction, the pulse impeller 3 may also allow the fluid passing through to form a pulse fluid with periodically changing flow rate.

[0074] In some embodiments, a hemispherical lower concave surface is formed at the downstream end of the eccentric tube 2, and the blades can be fitted with the lower concave surface. The blades of the pulse impeller 3 have arc-shaped edges, and the arc-shaped edges of the multiple blades are in the same concentric spherical surface, the center of the spherical surface is the intersection of the central axis of the impeller shaft 4 and the central axis of the shell; and the center of the lower concave surface is also the intersection of the central axis of the impeller shaft 4 and the central axis of the shell, and the arc-shaped edge of the blade is fitted with the lower concave surface to allow the blade to slide relative to the lower concave surface.

[0075] In some embodiments, a hemispherical upper concave surface is formed at the upstream end of the eccentric tube 2, and the eccentric hole is arranged at the upper concave surface. The concave structure formed around the eccentric hole of the eccentric tube 2 can make the fluid transition through the smooth spherical surface when entering the eccentric hole, avoiding the turbulence of the fluid here and causing excessive scouring of the eccentric tube 2.

[0076] The above describes the structure of the eccentric tube 2, which can be roughly cylindrical as a whole, and spherical concave surfaces are formed at both ends, and then an eccentric hole is processed; the influence of the eccentric hole on the shape of the spherical concave surface is not considered, this is just for the convenience of description, and technical personnel in this field can understand the specific form of the concave surface.

[0077] In some embodiments, the housing is provided with a gradually expanding portion transitionally connected to the upper concave surface. Figure 1 As shown, the part of the shell body that contacts the upper concave surface is gradually expanded, so as to realize a smooth transition from the smaller inner diameter of the shell body to the larger inner diameter of the upper concave surface, and avoid the formation of turbulence and excessive scouring. The gradual expansion here refers to the gradual increase of the inner diameter along the flow direction of the fluid.

[0078] In addition, the hydraulic pulse tool includes a tubular support seat 5 disposed downstream of the eccentric tube 2, and the support seat 5 has a through hole transitioning from the lower concave surface to the outlet of the housing. The through hole of the support seat 5 allows fluid to pass through, and one end of the support seat 5 is connected to the eccentric tube 2, and the other end is connected to the outlet of the housing. Figure 1 It can be seen that the pulse impeller 3 is accommodated at the connection between the eccentric tube 2 and the support seat 5. The inner diameter of the outlet of the support seat 5 is smaller than its inner diameter of the inlet, and its inner diameter of the inlet needs to be connected with the inner diameter of the lower concave surface of the eccentric tube 2, but the flow of the fluid passing through the eccentric tube 2 is limited by the eccentric hole, and the inner diameter of the eccentric hole is only 1 / 2 or less of the lower concave surface. Therefore, the inner diameter of the outlet of the shell is relatively smaller to match the flow of the eccentric hole, and the inner diameter of the outlet of the support seat 5 is also correspondingly smaller.

[0079] Wherein, the through hole includes a tapered hole, and a guide groove is arranged on the inner surface of the tapered hole. The support seat 5 is provided with a tapered hole at its outlet end so that the inner diameter gradually transitions to a level matching the outlet inner diameter of the shell. The tapering here means that the inner diameter gradually decreases in the direction of fluid flow. The tapered portion can make the inner diameter decrease smoothly, avoiding or alleviating the turbulence of the fluid here and causing excessive scouring. In addition, the guide groove can guide the fluid to flow in a specific direction, avoiding the deposition of solid particles in the sand-containing perforating fluid at the tapered hole. A plurality of guide grooves, for example, 5, can be arranged at intervals in the circumferential direction.

[0080] In some embodiments, the housing includes an upper joint 1 and a lower joint 6 that are detachably connected to each other. The lower end of the upper joint 1 is inserted into the upper end of the lower joint 6, and the lower end of the upper joint 1 can form an external thread, and the upper end of the lower joint 6 can form an internal thread, so as to allow the upper joint 1 and the lower joint 6 to be threaded together, and a sealing ring can be provided between the upper joint 1 and the lower joint 6 to improve the sealing between the two and prevent the fluid from leaking outward. In addition, the upper joint 1 and the lower joint 6 can be connected to each other by bolts to prevent the two from accidentally disengaging.

[0081] On the other hand, the present solution provides a tubular tool string, wherein the tubular tool string includes an oil pipe, a hydraulic ejector 12 connected to the oil pipe, and the hydraulic pulse tool 11 described in the above solution, wherein the hydraulic pulse tool 11 is arranged upstream of the hydraulic ejector 12. The hydraulic pulse tool 11 can make the perforating fluid or the fracturing fluid form a pulse fluid, and inject the perforating fluid or the fracturing fluid into the reservoir through the hydraulic ejector 12 to achieve perforating or fracturing operations.

[0082] In addition, refer to Figure 3As shown, the tubing tool string includes a continuous tubing connector 7, a one-way valve 8, a safety joint 9, a rigid centralizer 10, a bottom packer 13, a casing coupling locator 14, and a guide centralizer 15, which are arranged in sequence from top to bottom. The hydraulic ejector 12 and the hydraulic pulse tool 11 are arranged between the rigid centralizer 10 and the bottom packer 13.

[0083] On the other hand, the present invention also provides a method for hydraulic pulse perforation and fracturing, comprising the following steps: Lower the tubing string tool string described in the above solution into the well so that the hydraulic ejector 12 reaches the target reservoir; Setting the bottom packer 13; Conduct hydraulic pulse sandblasting perforation; Perform hydraulic fracturing.

[0084] The tubing tool string is lowered into the target depth of the well so that the hydraulic ejector 12 is located at the target reservoir, thereby enabling perforation and fracturing operations to be performed.

[0085] In addition, the hydraulic pulse perforation and fracturing combined method also includes: The tubing tool string is lifted so that the hydraulic ejector 12 reaches other reservoirs, and after the bottom packer 13 is set, hydraulic pulse sandblasting perforation and hydraulic fracturing are performed respectively.

[0086] Of course, in some cases, there may be multiple reservoirs in the formation, and the hydraulic ejector 12 may be lowered into the lowest reservoir first. Then, the tubing string is lifted to allow the hydraulic ejector 12 to rise to the upper adjacent reservoir, and after the bottom packer 13 is set, hydraulic pulse sandblasting perforation and hydraulic fracturing are performed again; this cycle is repeated to perform perforation and fracturing on all reservoirs.

[0087] This solution can realize the continuous tubing hydraulic pulse perforation and fracturing joint process. The tool has a simple structure, a large channel, and a high transmission efficiency. Backwashing and recoil can be performed during the fracturing process. There is no radial leakage, and a continuous stress wave impact effect can be formed. The effect of hydraulic jet perforation in the continuous tubing can be significantly improved. During the fracturing process, it can promote rock fatigue damage, reduce the fracture initiation pressure, induce microcracks and gradually communicate and penetrate natural cracks, thereby forming an effective volume fracture network and comprehensively improving the fracturing effect.

[0088] So far, various embodiments of the present disclosure have been described in detail. In order to avoid obscuring the concept of the present disclosure, some details known in the art are not described. Based on the above description, those skilled in the art can fully understand how to implement the technical solution disclosed here.

[0089] Although some specific embodiments of the present disclosure have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present disclosure. It should be understood by those skilled in the art that the above embodiments may be modified or some technical features may be replaced by equivalents without departing from the scope and spirit of the present disclosure. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there is no structural conflict.

Claims

1. A hydraulic pulse tool, characterized in that: The hydraulic pulse tool comprises a tubular housing, an eccentric tube (2) arranged in the housing, an impeller shaft (4) arranged downstream of the eccentric tube (2), and a pulse impeller (3) having a plurality of blades rotatably arranged on the impeller shaft (4), wherein the impeller shaft (4) extends perpendicular to the central axis of the housing, the eccentric tube (2) has an eccentric hole eccentrically arranged relative to the central axis of the housing, any two adjacent blades can enclose a fluid cavity connected to the eccentric hole with the eccentric tube (2), and the volume of the fluid cavity changes with the rotation of the pulse impeller (3).

2. The hydraulic pulse tool according to claim 1, characterized in that: The central axis of the impeller shaft (4) and the central axis of the housing intersect with each other, and the eccentric hole is arranged on one side of a plane passing through the central axis of the impeller shaft (4) and the central axis of the housing.

3. The hydraulic pulse tool according to claim 2, characterized in that: A hemispherical lower concave surface is formed at the downstream end of the eccentric tube (2), and the blades can be clearance-matched with the lower concave surface.

4. The hydraulic pulse tool according to claim 3, characterized in that: The upstream end of the eccentric tube (2) is formed with a hemispherical upper concave surface, and the eccentric hole is arranged on the upper concave surface.

5. The hydraulic pulse tool according to claim 4, characterized in that: The shell body is provided with a gradually expanding portion which is transitionally connected with the upper concave surface.

6. The hydraulic pulse tool according to claim 3, characterized in that: The hydraulic pulse tool comprises a tubular support seat (5) arranged downstream of the eccentric tube (2), and the support seat (5) has a through hole that transitions from the lower concave surface to the outlet of the housing.

7. The hydraulic pulse tool according to claim 6, characterized in that: The through hole comprises a tapered hole, and a guide groove is arranged on the inner surface of the tapered hole.

8. The hydraulic pulse tool according to claim 6, characterized in that: The housing comprises an upper joint (1) and a lower joint (6) which are detachably connected to each other.

9. A tubular tool string, characterized in that: The tubing tool string comprises an oil pipe, a hydraulic ejector (12) connected to the oil pipe, and a hydraulic pulse tool (11) according to any one of claims 1 to 8, wherein the hydraulic pulse tool (11) is arranged upstream of the hydraulic ejector (12).

10. The tubular tool string according to claim 9, characterized in that: The tubing tool string comprises a continuous tubing connector (7), a one-way valve (8), a safety joint (9), a rigid centralizer (10), a bottom packer (13), a casing coupling positioner (14), and a guide centralizer (15) which are arranged in sequence from top to bottom. The hydraulic ejector (12) and the hydraulic pulse tool (11) are arranged between the rigid centralizer (10) and the bottom packer (13).

11. A hydraulic pulse perforation and fracturing combined method, characterized in that: The following steps are involved: Lowering the tubing tool string of claim 10 into the well so that the hydraulic ejector (12) reaches the target reservoir; Setting the bottom packer (13); Conduct hydraulic pulse sandblasting perforation; Perform hydraulic fracturing.

12. The hydraulic pulse perforation and fracturing combined method according to claim 11, characterized in that: Also includes: The tubing tool string is lifted so that the hydraulic ejector (12) reaches other reservoirs, and after the bottom packer (13) is set, hydraulic pulse sandblasting perforation and hydraulic fracturing are performed respectively.

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