Laser slotting and fracturing balance tool

Abstract

The invention relates to the technical field of fracturing well completion in the field of oil development, in particular to a laser slotting fracturing balance tool. The laser slotting and fracturing balancing tool comprises a main body; a plurality of through holes are symmetrically formed in the outer wall of the main body, shear pins are arranged in the through holes, the connecting sleeve is connected with the sand prevention sliding sleeve and the main body, a baffle ring is arranged between the upper connector and the connecting sleeve, a plurality of laser slits are formed in the outer wall of the sand prevention sliding sleeve, the lower end of the main body is connected with the lower connector, and the lower connector positions the outer sleeve. According to the laser slotting fracturing balance tool, through cooperation of the sectioning sliding sleeve and the sand prevention sliding sleeve, the sand prevention sliding sleeve moves downwards through pressurization to shear off the shear pin, the multiple laser slots in the outer wall of the sand prevention sliding sleeve are aligned with the through holes formed in the outer wall of the main body, and the interior and the exterior of an oil pipe are communicated; the pressure difference between a fracturing layer and a balance layer is controlled to be zero, the shearing force of fracturing construction on an interlayer is reduced, and therefore it is guaranteed that construction pressure cannot damage the interlayer to cause layer channeling.

Description

Technical Field

[0001] The present invention relates to the technical field of fracturing and completion in the field of petroleum development, and in particular to a laser slotting fracturing balancing tool. Background Art

[0002] Conventional fracturing technology, a primary method for oilfield production, is widely used to tap into remaining oil resources. Under current technical conditions, the commonly used fracturing string in oilfields is the sliding sleeve, layered fracturing string. This string requires interlayer thickness greater than 1.5m to ensure that pressure does not damage the interlayer during operation, thereby preventing oil layer channeling and ensuring normal well production. However, after years of injection and production, as oilfields continue to develop, residual oil gradually migrates from interlayers to inner layers. This change causes the interlayer thickness to gradually decrease, weakening its shear resistance. In these circumstances, the sliding sleeve, layered fracturing string is no longer sufficient for normal operation. Summary of the Invention

[0003] (1) Technical issues to be resolved The present invention provides a laser slit fracturing balancing tool to overcome the problem in the prior art that normal fracturing construction cannot be carried out when the interlayer thickness is less than 1.5m.

[0004] (2) Technical solution To achieve the above-mentioned object, the present invention provides a laser slitting and fracturing balancing tool, comprising: a main body; The main body is a hollow cylindrical structure, and a plurality of through holes are symmetrically provided on the outer wall of the main body, and a plurality of shear pins are provided in the through holes; The main body is provided with a sand-proof sliding sleeve, the lower end of which is embedded in the main body. The sand-proof sliding sleeve is a hollow cylindrical structure and is positioned by a shear pin. The upper end of the sand-proof sliding sleeve is embedded in the connecting sleeve, the lower end of the connecting sleeve is provided with a main body, and the upper end of the connecting sleeve is provided with an upper joint; A retaining ring is provided between the upper joint and the connecting sleeve, the retaining ring is a circular ring structure, and a petal sliding sleeve is provided in the connecting sleeve; The outer wall of the upper end of the sand-proof sliding sleeve is provided with a plurality of laser cut slits; The lower end of the main body is covered with an outer sleeve, and the lower end of the main body is threadedly connected to a lower joint, and the lower joint positions the outer sleeve.

[0005] Preferably, an expansion spring is provided in the petal sliding sleeve, and the expansion spring can expand the petal sliding sleeve.

[0006] Preferably, the upper end of the main body is provided with a step on the outer edge, the step matches the size of the petal sliding sleeve, and the petal sliding sleeve can expand outward inside the step.

[0007] Preferably, the laser slits are divided into several sections, and each section of the laser slits is respectively opposite to the through holes provided on the outer wall of the main body. The laser slits can make the inside and outside of the oil pipe connected, so that the pressure is balanced.

[0008] Preferably, the laser slits are used to filter the discharged liquid when discharging the liquid in the sand control sleeve. The laser slits can block the passage of sand and gravel to play a role in sand control.

[0009] Preferably, it also includes a steel ball, which is arranged in the upper joint. The size of the steel ball is larger than the inner diameter of the petal sliding sleeve. The steel ball is used to close the petal sliding sleeve. Under the action of the steel ball, the sand-proof sliding sleeve can be pressed downward.

[0010] Preferably, the shear pin can be sheared off from the upper end by the sand control sliding sleeve under pressure.

[0011] Preferably, the size of the steel ball is smaller than the inner diameter of the sand-control sleeve, and the steel ball can pass through the sand-control sleeve, the main body and the lower joint and fall into the well.

[0012] Preferably, the split sliding sleeve can allow the steel ball to pass through in the expanded state.

[0013] Preferably, it also includes three sealing rings, which include: a first sealing ring, a second sealing ring and a third sealing ring. The first sealing ring is mounted on the upper end of the connecting sleeve, the second sealing ring is mounted on the lower end of the connecting sleeve, and the third sealing ring is provided at the lower end of the main body. The first sealing ring and the second sealing ring are used to prevent leakage at both ends of the connecting sleeve, and the third sealing ring is used to prevent leakage at the connection between the main body and the lower joint.

[0014] (3) Beneficial effects The present invention provides a laser slit fracturing balancing tool, which can be achieved through the cooperation between the petal sliding sleeve and the sand-proof sliding sleeve. The sand-proof sliding sleeve is moved downward by pressurization, and the sand-proof sliding sleeve shears the shear pin from the upper end, so that the multiple laser slits provided on the outer wall of the sand-proof sliding sleeve are aligned with the through holes provided on the outer wall of the main body, so that the oil pipe is connected inside and outside. By utilizing the principle of hydraulics, the pressure difference between the fracturing layer and the balancing layer is controlled to zero, and the shear force of the interlayer during fracturing construction is reduced, thereby meeting the fracturing potential when the upper interlayer is less than 1.5m, and ensuring that the construction pressure will not damage the interlayer and cause layer channeling. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic structural diagram of the laser slitting and fracturing balancing tool of the present invention is shown.

[0016] Among them: 1: upper joint; 2: retaining ring; 3: split sliding sleeve; 4: sand-proof sliding sleeve; 5: connecting sleeve; 6: main body; 7: outer sleeve; 8: shear pin; 9: lower joint; 10: laser cutting. DETAILED DESCRIPTION

[0017] The present invention is described in detail below with reference to the accompanying drawings and embodiments, and the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0018] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by “up”, “down”, “left”, “right”, “inside”, “outside”, “top”, “bottom”, etc. are all based on the directions or positional relationships shown in the accompanying drawings. The purpose is only to facilitate the description of the present invention and simplify the description. It does not indicate or imply that the referred parts must have a specific direction, be constructed and operated in a specific direction. Therefore, it cannot be understood as a limitation on the present invention.

[0019] like Figure 1 As shown, the present invention provides a laser slitting and fracturing balancing tool, comprising: a main body 6; The main body 6 is a hollow cylindrical structure. The outer wall of the main body 6 is symmetrically provided with a plurality of through holes. The through holes are provided with a plurality of shear pins 8. The main body 6 is provided with a sand-proof sliding sleeve 4. The sand-proof sliding sleeve 4 is a hollow cylindrical structure. The lower end of the sand-proof sliding sleeve 4 is embedded in the main body 6. The upper end of the main body 6 is provided with a step on the outer edge. The step matches the size of the petal sliding sleeve 3. The outer wall of the sand-proof sliding sleeve 4 is evenly provided with a plurality of laser cuts 10. The sand-proof sliding sleeve 4 is positioned by the shear pins 8. The shear pin 8 is inserted into a plurality of through holes symmetrically provided on the outer wall of the main body 6. The shear pin 8 restricts the downward movement of the sand control sleeve 4. The shear pin 8 can be sheared from the upper end by the sand control sleeve 4 under pressure.

[0020] The connecting sleeve 5 is a hollow cylindrical structure, with external threads at both ends of the connecting sleeve 5. The upper end of the connecting sleeve 5 is covered with a first sealing ring, and the lower end of the connecting sleeve 5 is covered with a second sealing ring. The lower end of the connecting sleeve 5 is threadedly connected to the upper end of the main body 6, and the upper end of the connecting sleeve 5 is threadedly connected to the upper joint 1. A retaining ring 2 is provided between the upper joint 1 and the connecting sleeve 5. The retaining ring 2 is a circular ring structure. The upper joint 1 is a hollow cylindrical structure, and the lower end of the upper joint 1 is provided with an internal thread. The laser slit 10 is provided with two sections, upper and lower, respectively. Each section of the laser slit 10 is opposite to the through hole provided on the outer wall of the main body 6. The laser slit 10 can make the inside and outside of the oil pipe connected to each other, so that the pressure is balanced. The width of the laser slit 10 is 0.2 mm. The 0.2 mm laser slit 10 is used to filter the discharged liquid when the liquid in the sand-proof sliding sleeve 4 is discharged. The laser slit 10 can prevent sand and gravel from passing through and play a role in sand prevention. The first sealing ring and the second sealing ring are used to prevent leakage at both ends of the connecting sleeve 5.

[0021] The connecting sleeve 5 is provided with a split sleeve 3, and the split sleeve 3 is provided with an expansion spring, which can expand the split sleeve 3. The upper end of the main body 6 is provided with a step on the outer edge, which matches the size of the split sleeve 3. The split sleeve 3 can expand under the action of the step.

[0022] The lower end of the main body 6 is covered with a jacket 7, and the lower end of the main body 6 is threadedly connected to the lower joint 9, which positions the jacket 7. The lower end of the main body 6 is provided with a third sealing ring, which is used to prevent leakage at the connection between the main body 6 and the lower joint 9.

[0023] The upper joint 1 is provided with a steel ball, the size of which is larger than the inner diameter of the split sleeve 3. The steel ball is used to close the split sleeve 3. Under the action of the steel ball, the anti-sand sleeve 4 can be pressed downward by pressure, and the split sleeve 3 can allow the steel ball to pass through in the expanded state. The steel ball is smaller than the inner diameter of the sand sleeve 4 and can pass through the sand sleeve 4, the main body 6 and the lower joint 9 and fall into the well. When using the laser slit fracturing balancing tool, a steel ball needs to be put into the upper joint 1. The steel ball seals the upper end of the upper joint 1, so that the sand-proof sliding sleeve 4 can move downward under the action of pressure. The sand-proof sliding sleeve 4 shears the shear pin 8 from top to bottom, so that the sand-proof sliding sleeve 4 moves downward in the main body 6 so that the laser slit 10 on the outer wall of the sand-proof sliding sleeve 4 is aligned with the through hole, so that the inside and outside of the oil pipe are connected and the pressure of the balance layer is balanced.

[0024] The following is a detailed introduction to the actual working scenario of the laser slit fracturing balancing tool.

[0025] In actual work, the laser slitting and fracturing balancing tool can be used in series with multi-stage tools such as packers. The release is achieved by adjusting the size of the internal sliding sleeve and inserting different steel balls. When the upper end of the oil pipe 1 is in the oil well, the oil pump 8 is turned on the oil pump 8 and the oil level sensor 2 is turned on, so that the oil pump 8 can be turned on the oil pump 8 at the same time.

[0026] The laser slotted fracturing balancing tool was used in five wells, reducing trips and runs of the fracturing string by five times, reducing secondary fracturing operations by five times, and reducing well occupation by 10 days. Fracturing operations on site proceeded smoothly, with stable pressure, clear shearing, and excellent post-fracture results. The average daily oil production increase per well was approximately 3.5 tons / day, at an investment cost of 21,950 yuan. The laser slotted fracturing balancing tool, costing 4,390 yuan per set, saved 480,800 yuan, including 119,550 yuan in operational costs, five trips and runs of the fracturing string at a cost of 23,910 yuan each, 361,250 yuan in fracturing costs, and five string changes at a cost of 72,250 yuan each. This saved 148,400 yuan in oil efficiency and reduced well occupation by 10 days. Initially, the average daily oil production increase after the measure was 3.5 tons / day, with 35 tons of oil production reduced, resulting in a per-ton oil benefit of 4,240 yuan, or 148,400 yuan in oil efficiency.

[0027] It can be understood that the above-mentioned embodiments mentioned in the present invention can be combined with each other to form combined embodiments without violating the principle logic. Due to space limitations, the present invention will not elaborate on them.

[0028] Those skilled in the art will understand that in the above-mentioned method of the specific implementation method, the writing order of each step does not mean a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of each step should be determined by its function and possible internal logic.

[0029] The laser slit fracturing balancing tool provided by the present invention cooperates between the split sleeve 3 and the sand-proof sleeve 4. The sand-proof sleeve 4 is moved downward by pressurization. The sand-proof sleeve 4 cuts off the shear pin 8 from the upper end, so that the multiple laser slits 10 provided on the outer wall of the sand-proof sleeve 4 are aligned with the through holes provided on the outer wall of the main body 6, so that the inside and outside of the oil pipe are connected. By utilizing the principles of hydraulics, the pressure difference between the fracturing layer and the balancing layer is controlled to zero, reducing the shear force of the interlayer during fracturing construction, thereby achieving the purpose of meeting the fracturing potential when the upper interlayer is less than 1.5m, and ensuring that the construction pressure will not damage the interlayer and cause layer channeling.

[0030] While various embodiments of the present invention have been described above, the above descriptions are intended to be illustrative, non-exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or technological improvements in the marketplace, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A laser slitting and fracturing balancing tool, characterized in that: include: Subject (6); The main body (6) is a hollow cylindrical structure, and a plurality of through holes are symmetrically provided on the outer wall of the main body (6), and a plurality of shear pins (8) are provided in the through holes; A sand-proof sliding sleeve (4) is provided in the main body (6), the lower end of the sand-proof sliding sleeve (4) is embedded in the main body (6), the sand-proof sliding sleeve (4) is a hollow cylindrical structure, and the sand-proof sliding sleeve (4) is positioned by a shear pin (8); The upper end of the sand-proof sliding sleeve (4) is embedded in the connecting sleeve (5), the lower end of the connecting sleeve (5) is provided with a main body (6), and the upper end of the connecting sleeve (5) is provided with an upper joint (1); A retaining ring (2) is provided between the upper joint (1) and the connecting sleeve (5), the retaining ring (2) being a circular ring structure, and a petal sliding sleeve (3) is provided in the connecting sleeve (5); The outer wall of the upper end of the sand-proof sliding sleeve (4) is provided with a plurality of laser cut slits (10); The lower end of the main body (6) is covered with an outer sleeve (7), and the lower end of the main body (6) is threadedly connected to a lower joint (9), and the lower joint (9) positions the outer sleeve (7).

2. The laser slitting and fracturing balancing tool according to claim 1, characterized in that: An expansion spring is provided in the petal sliding sleeve (3), and the expansion spring can cause the petal sliding sleeve (3) to expand.

3. The laser slitting and fracturing balancing tool according to claim 1, characterized in that: The upper end of the main body (6) is provided with a step on the outer edge, and the step matches the size of the petal sliding sleeve (3), and the petal sliding sleeve (3) can expand outward inside the step.

4. The laser slitting and fracturing balancing tool according to claim 1, characterized in that: The laser slits (10) are arranged in several sections, and each section of the laser slits (10) is respectively opposite to a through hole provided on the outer wall of the main body (6). The laser slits (10) can connect the inside and outside of the oil pipe, thereby achieving pressure balance.

5. The laser slitting and fracturing balancing tool according to claim 1, characterized in that: The laser slits (10) are used to filter the discharged liquid when the liquid in the sand-proof sliding sleeve (4) is discharged. The laser slits (10) can prevent sand and gravel from passing through, thereby playing a role in sand prevention.

6. The laser slitting and fracturing balancing tool according to claim 1, characterized in that: It also includes a steel ball, which is arranged in the upper joint (1). The size of the steel ball is larger than the inner diameter of the petal sliding sleeve (3). The steel ball is used to close the petal sliding sleeve (3). Under the action of the steel ball, the sand-proof sliding sleeve (4) can be pressed downward.

7. The laser slitting and fracturing balancing tool according to claim 1, characterized in that: The shear pin (8) can be sheared from the upper end by the sand-proof sliding sleeve (4) under pressure.

8. The laser slitting and fracturing balancing tool according to claim 6, characterized in that: The steel ball is smaller than the inner diameter of the sand-proof sliding sleeve (4), and the steel ball can pass through the sand-proof sliding sleeve (4), the main body (6), and the lower joint (9) and fall into the well.

9. The laser slitting and fracturing balancing tool according to claim 6, characterized in that: The split sliding sleeve (3) can allow the steel ball to pass through in the expanded state.

10. The laser slitting and fracturing balancing tool according to claim 1, characterized in that: The invention also includes three sealing rings, which include a first sealing ring, a second sealing ring and a third sealing ring. The upper end of the connecting sleeve (5) is covered with the first sealing ring, the lower end of the connecting sleeve (5) is covered with the second sealing ring, and the lower end of the main body (6) is provided with a third sealing ring. The first sealing ring and the second sealing ring are used to prevent leakage at both ends of the connecting sleeve (5), and the third sealing ring is used to prevent leakage at the connection between the main body (6) and the lower joint (9).

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