A sand-prevention type temporary blocking valve capable of being repeatedly opened and closed and having a reverse circulation function

Abstract

The application discloses a repeatedly openable and closeable sand-preventing temporary blocking valve with a reverse circulation function, which comprises an upper joint, a reverse circulation cylinder sleeve, a spring supporting sleeve, a circulating valve compression spring, a reverse circulation piston, a sealing packing, an intermediate joint, a valve plate compression spring, a valve plate pushing cylinder, a valve plate and a lower joint. One end of the reverse circulation cylinder sleeve is connected with the upper joint, and the other end is connected with one end of the intermediate joint. The upper end of the reverse circulation cylinder sleeve is provided with the circulating valve compression spring and the spring supporting sleeve, and the lower end of the reverse circulation cylinder sleeve is provided with the reverse circulation piston and the sealing packing. The other end of the intermediate joint is connected with one end of a valve plate cylinder sleeve, and the other end of the valve plate cylinder sleeve is connected with the lower joint. The lower joint is provided with the valve plate in the middle, the shear pin and the pin plug cap in the lower part, and the valve plate compression spring and the valve plate pushing cylinder in the inside. The bottom dragging fracturing packer is matched, so that the multi-layer fracturing in the segmented mode without bridge plug isolation can be realized. When sand blocking occurs, the reverse circulation sand washing can be carried out.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of horizontal well multi-layer fracturing in oil and gas fields, and particularly relates to a sand-preventing temporary blocking valve capable of being repeatedly opened and closed and having a reverse circulation function. BACKGROUND

[0002] At present, domestic shale gas horizontal well fracturing mainly adopts mechanical bridge plug to segment, including different types of fast drilling bridge plug, large-diameter bridge plug and soluble bridge plug.

[0003] The bridge plug segmentation process has good effect, but requires high wellbore drift diameter, the fast drilling bridge plug needs to be drilled and ground after fracturing, and has high cost; the soluble bridge plug has poor solubility and poor controllability of dissolution time; the large-diameter bridge plug has difficulty in pumping and processing, and after fracturing, the wellbore is not full-diameter and affects liquid discharge and subsequent operations (such as sand washing, production logging and oil pipe lowering). SUMMARY

[0004] In order to overcome the shortcomings of the prior art, the present application provides a sand-preventing temporary blocking valve capable of being repeatedly opened and closed and having a reverse circulation function, which can realize multi-layer fracturing in a segmentation mode without bridge plug isolation in cooperation with a bottom drag fracturing packer, and when sand plugging occurs, reverse circulation sand washing and well washing can be performed. Compared with other multi-layer fracturing construction processes, the sand-preventing temporary blocking valve does not need to drill and remove the fast drilling bridge plug, does not need to wait for the dissolution time of the soluble bridge plug, meets the production requirements of full-diameter casing after fracturing, is also suitable for pipe damage casing deformation wells, does not require well conditions, and can perform multi-stage fracturing construction without maintenance costs for casing deformation wells.

[0005] To achieve the above technical purposes, the present application provides the following scheme: a sand-preventing temporary blocking valve capable of being repeatedly opened and closed and having a reverse circulation function, comprising an upper joint, a reverse circulation cylinder sleeve, a spring support sleeve, a circulating valve compression spring, a reverse circulation piston, a sealing packing, an intermediate joint, a valve plate compression spring, a valve plate push cylinder, a valve plate and a lower joint, one end of the reverse circulation cylinder sleeve is connected with the upper joint, the other end is connected with one end of the intermediate joint, the upper end of the reverse circulation cylinder sleeve is provided with the circulating valve compression spring and the spring support sleeve inside, the lower end of the reverse circulation cylinder sleeve is provided with the reverse circulation piston and the sealing packing inside, the other end of the intermediate joint is connected with one end of a valve plate cylinder sleeve, the other end of the valve plate cylinder sleeve is connected with the lower joint, the valve plate is arranged in the middle of the lower joint, the lower part is provided with a shear pin and a pin plug cap, and the inside is provided with the valve plate compression spring and the valve plate push cylinder.

[0006] In the above technical scheme, the upper end of the reverse circulation cylinder is connected with the lower end of the upper joint through threads, and is sealed through a first O-shaped sealing ring, the middle and lower sections of the reverse circulation cylinder sleeve are provided with uniformly distributed waist-shaped grooves to provide a reverse circulation liquid flow channel, and the tail is connected with the outer threads of the intermediate joint through threads and is sealed through a second O-shaped sealing ring.

[0007] In the technical scheme, the upper end surface of the spring support sleeve is provided with threads, the bottom of the threads is provided with a cylindrical liquid inlet hole, the inside of the cylindrical liquid inlet hole is provided with a first sandproof internal hexagonal screw, the bottom of the first sandproof internal hexagonal screw is provided with uniformly distributed sand filtering holes, and the liquid inlet hole is satisfied with the liquid entering the internal chamber of the reverse circulation cylinder sleeve.

[0008] In the technical scheme, the upper end surface of the spring support sleeve is provided with threads, the bottom of the threads is provided with a cylindrical liquid inlet hole, the inside of the cylindrical liquid inlet hole is provided with a first sandproof internal hexagonal screw, the bottom of the first sandproof internal hexagonal screw is provided with uniformly distributed sand filtering holes, and the liquid inlet hole is satisfied with the liquid entering the internal chamber of the reverse circulation cylinder sleeve.

[0009] In the technical scheme, the upper end surface of the spring support sleeve is provided with threads, the bottom of the threads is provided with a cylindrical liquid inlet hole, the inside of the cylindrical liquid inlet hole is provided with a first sandproof internal hexagonal screw, the bottom of the first sandproof internal hexagonal screw is provided with uniformly distributed sand filtering holes, and the liquid inlet hole is satisfied with the liquid entering the internal chamber of the reverse circulation cylinder sleeve.

[0010] In the technical scheme, the upper end surface of the spring support sleeve is provided with threads, the bottom of the threads is provided with a cylindrical liquid inlet hole, the inside of the cylindrical liquid inlet hole is provided with a first sandproof internal hexagonal screw, the bottom of the first sandproof internal hexagonal screw is provided with uniformly distributed sand filtering holes, and the liquid inlet hole is satisfied with the liquid entering the internal chamber of the reverse circulation cylinder sleeve.

[0011] In the technical scheme, the upper end surface of the spring support sleeve is provided with threads, the bottom of the threads is provided with a cylindrical liquid inlet hole, the inside of the cylindrical liquid inlet hole is provided with a first sandproof internal hexagonal screw, the bottom of the first sandproof internal hexagonal screw is provided with uniformly distributed sand filtering holes, and the liquid inlet hole is satisfied with the liquid entering the internal chamber of the reverse circulation cylinder sleeve.

[0012] In the technical scheme, the upper end surface of the spring support sleeve is provided with threads, the bottom of the threads is provided with a cylindrical liquid inlet hole, the inside of the cylindrical liquid inlet hole is provided with a first sandproof internal hexagonal screw, the bottom of the first sandproof internal hexagonal screw is provided with uniformly distributed sand filtering holes, and the liquid inlet hole is satisfied with the liquid entering the internal chamber of the reverse circulation cylinder sleeve.

[0013] In the technical scheme, the upper end surface of the spring support sleeve is provided with threads, the bottom of the threads is provided with a cylindrical liquid inlet hole, the inside of the cylindrical liquid inlet hole is provided with a first sandproof internal hexagonal screw, the bottom of the first sandproof internal hexagonal screw is provided with uniformly distributed sand filtering holes, and the liquid inlet hole is satisfied with the liquid entering the internal chamber of the reverse circulation cylinder sleeve.

[0014] The beneficial effects of the present application are as follows: when multi-layer fracturing is performed, the bottom drag packer can be used to realize the sealing between the inside of the oil pipe and the annulus of the oil jacket, the cost of lowering the bridge plug and drilling the bridge plug is saved, the non-value-added waiting time for waiting for the complete dissolution of the soluble bridge plug is saved, the deficiency of the insufficient size of the production channel after the pressure of the large diameter bridge plug is eliminated, and when the pipe string is lowered, the valve plate can be controlled to be in an open state, the downhole liquid can be automatically filled into the oil pipe, automatic liquid filling is realized, when fracturing is needed, the packer is set after sealing, the annulus is hit with low pressure to initially close the one-way valve, after fracturing is completed, the valve plate is automatically closed, the control of the pressure in the oil pipe is realized, after the drag packer is unsealed, the drag packer can be dragged to other layers again, the valve plate will be opened again, and the pressure construction of the second layer is performed, the efficiency is high, and the cost is low. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a schematic diagram of the half-sectional structure of the present application.

[0016] Figure 2 yes Figure 1 Enlarged view of point A in the reverse circulation sand control mechanism.

[0017] Figure 3 yes Figure 1 Enlarged view of point B in the reverse circulation piston sealing mechanism.

[0018] Figure 4 yes Figure 1 Enlarged view of point C of the sand-proof mechanism of the piston in the middle valve plate.

[0019] Figure 5 yes Figure 1 Enlarged view of point D in the middle valve plate mechanism.

[0020] Figure 6 yes Figure 1 Enlarged view of point E of the initial fixing mechanism of the middle valve plate push cylinder.

[0021] The components are as follows: 1. Upper connector; 2. First O-ring seal; 3. First sand-resistant hexagon socket head cap screw; 4. Circulation valve compression spring; 5. Reverse circulation cylinder liner; 6. Spring support sleeve; 7. Second O-ring seal; 8. Third O-ring seal; 9. Reverse circulation piston; 10. Sealing packing; 11. Fourth O-ring seal; 12. Intermediate connector; 13. Fifth O-ring seal; 14. Valve plate cylinder liner; 15. Sixth O-ring seal; 16. Valve plate compression spring; 17. Second sand-resistant hexagon socket head cap screw; 18. Valve plate push cylinder; 19. Seventh O-ring seal; 20. Eighth O-ring seal; 21. Ninth O-ring seal; 22. Lower connector; 23. Valve plate; 24. Tenth O-ring seal; 25. Shear pin; 26. Pin cap. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0023] like Figures 1 to 6 The aforementioned sand-proof temporary plugging valve with reversible switching and reverse circulation function includes an upper connector 1, a reverse circulation cylinder liner 5, a spring support sleeve 6, a circulation valve compression spring 5, a reverse circulation piston 9, a sealing packing 10, an intermediate connector 12, a valve plate compression spring 16, a valve plate push cylinder 18, a valve plate 23, and a lower connector 22. One end of the reverse circulation cylinder liner 5 is connected to the upper connector 1, and the other end is connected to one end of the intermediate connector 12. The upper end of the reverse circulation cylinder liner 5 is provided with a circulation valve compression spring 4 and a spring support sleeve 6, and the lower end of the reverse circulation cylinder liner 5 is provided with a reverse circulation piston 9 and a sealing packing 10. The other end of the intermediate connector 12 is connected to one end of the valve plate cylinder liner 14, and the other end of the valve plate cylinder liner 14 is connected to the lower connector 22. The lower connector 22 is provided with a valve plate 23 in the middle, and a shear pin 25 and a pin plug 26 are provided at its lower part. The valve plate compression spring 16 and the valve plate push cylinder 18 are provided inside the lower connector 22.

[0024] In the above technical solution, the upper end of the upper joint 1 is connected with the upper end of the reverse circulation cylinder 5 through threads, and is sealed by the first O-shaped sealing ring 2. The middle and lower sections of the reverse circulation cylinder 5 are provided with uniformly distributed waist-shaped grooves to provide a reverse circulation liquid flow channel. The tail is connected with the outer threads of the intermediate joint through threads, and is sealed by the second O-shaped sealing ring 7.

[0025] In the above technical solution, the upper end face of the spring support sleeve 6 is provided with threads, the bottom of the threads is provided with a cylindrical liquid inlet hole, the inside of the cylindrical liquid inlet hole is provided with a first sandproof internal hexagonal screw 3, and the bottom of the first sandproof internal hexagonal screw 3 is provided with uniformly distributed sand filtering holes. The sand filtering holes can satisfy the liquid entering the internal cavity of the reverse circulation cylinder sleeve 5, but sand or other solid-phase particles cannot enter the internal cavity, so that the sandproof function of the cavity is achieved, the rebound mechanism is ensured not to be stuck, and the function of repeatedly opening the reverse circulation valve is achieved.

[0026] In the above technical solution, the upper end face of the reverse circulation valve compression spring 4 is in contact with the lower end face of the upper step of the spring support sleeve 6, and the lower end face of the spring support sleeve 6 is in contact with the upper end face of the reverse circulation piston 9, and the power storage function of the rebound of the reverse circulation valve is provided.

[0027] In the above technical solution, the third O-shaped sealing ring 8 and the fourth O-shaped sealing ring 11 are respectively arranged in the inner and outer wall sealing grooves of the upper end of the reverse circulation piston 9, and the middle and lower sections are in interference extrusion sealing with the inner wall of the sealing packing 10.

[0028] The second O-shaped sealing ring 7 and the third O-shaped sealing ring 8 realize the functions of sliding sealing and sandproof. The lower side of the third O-shaped sealing ring 8 on the outer side of the upper end has a small step. When external pressure is applied to the outside, the step is pushed upward, so that the reverse circulation valve compression spring is compressed, and the lowermost end of the reverse circulation valve is moved to the upper end of the uniformly distributed waist-shaped grooves in the middle and lower sections of the reverse circulation cylinder sleeve 5, so that the reverse circulation channel is opened. After pressure relief, the reverse circulation valve compression spring 4 exerts the elastic force to push the reverse circulation piston 9 downward again, and the reverse circulation channel is closed again.

[0029] In the above technical solution, a plurality of uniformly distributed triangular threaded holes are arranged on the circumference of the middle and lower sections of the valve plate cylinder sleeve 14. The bottom of each triangular threaded hole is provided with a small-diameter through hole, and the second sandproof internal hexagonal screw 17 with sand filtering holes is arranged in each triangular threaded hole. The second sandproof internal hexagonal screw 17 prevents the solid-phase particles from entering the spring cavity in the middle and lower sections of the valve plate cylinder sleeve, avoids the sticking of the valve plate compression spring mechanism, and realizes the sandproof spring energy storage function.

[0030] In the above technical scheme, the fifth O-shaped sealing ring 13 is arranged between the intermediate joint 12 and the valve plate cylinder sleeve 14, the sixth O-shaped sealing ring 15 is arranged on the upper part of the valve plate push cylinder 18 and is in sliding sealing with the inner wall of the valve plate cylinder sleeve, the valve plate push cylinder 18 can push away the valve plate 23 when the valve plate compression spring 16 is compressed and is lowered, and the channel is opened so that the fracturing fluid enters the lower oil pipe and the fractured layer, the uniformly distributed holes at the tail end are matched with the shear pin 25, the shear pin 25 limits the valve plate push cylinder 18 when it is initially put into the well, and the opening of the valve plate 12 is realized, and the liquid is not needed to be poured while the pipe column is lowered.

[0031] In the above technical scheme, the seventh O-shaped sealing ring 19 is arranged between the valve plate cylinder sleeve 14 and the lower joint 12, the eighth O-shaped sealing ring 20 is arranged between the valve plate 23 and the valve plate push cylinder 18, and the ninth O-shaped sealing ring 21 is arranged between the valve plate 23 and the lower joint 22.

[0032] The outer surface of the valve plate push cylinder 18 is in sliding sealing with the ninth O-shaped sealing ring 21, the tail hole is matched with the shear pin 25, the spring potential energy of the valve plate compression spring 16 in the compressed state is locked, the valve plate 23 is kept in the opened state when it is put into the well, after the purpose layer is reached, the shear pin 25 is cut off by annular pressure, the valve plate push cylinder 18 is moved upward under the action of the spring back elasticity of the valve plate compression spring 16, the torsional spring of the valve plate 23 twists the valve plate clockwise by 90°, and extrusion sealing is formed with the vulcanized rubber at the lower end of the valve plate seat, the greater the lower pressure is, the greater the extrusion force of the vulcanized rubber at the lower end of the valve plate 23 and the valve plate seat is, and the sealing is more tight.

[0033] In the above technical scheme, the lower part of the lower joint 22 is provided with a threaded hole, a pin plug cap 26 and a tenth O-shaped sealing ring 24.

[0034] The lower end of the valve plate cylinder sleeve 14 has two threaded holes with different sizes, the smaller one is used for installing the shear pin 25 and is connected with the tail hole of the valve plate push cylinder 18, so that the valve plate push cylinder 18 is prevented from moving upward and is fixed in the initial state when it is put into the well, the force value of the shear pin 25 can be adjusted according to the specific construction requirement, so as to adjust the initial pressure of the closed valve plate 23.

[0035] The working principle of the sand control type temporary blocking valve is as follows: the annulus pressure of the pipe string is controlled by the non-well killing operation machine, the pressure in the oil pipe is controlled by the one-way valve plate mechanism, and the upper part of the multiple setting mechanical packer is connected. The tool string is sent into the target layer by the oil pipe, the multiple setting mechanical packer is first set to seal the oil jacket annulus, and low pressure is punched in the oil jacket annulus. The pressure acts on the cross section of the reverse circulation valve and the valve plate push cylinder. At this time, the reverse circulation valve will not be pushed open under low pressure, the second valve plate push cylinder will cut the tail shear pin and move upward, the valve plate is automatically closed, and after pressure relief, the pressure in the oil pipe acts on the valve plate push cylinder, the valve plate push cylinder moves downward to push the valve plate open again and protect the valve plate from being washed by the liquid flow. The first layer is fractured, and after completion, the oil pipe is depressurized, the valve plate is automatically closed, the pipe string is lifted to unblock the packer, and the pipe string is lifted to the second layer and the first layer is subjected to pressure construction. In this way, the purpose of multi-layer pressure construction is achieved.

[0036] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A sand-proof temporary plugging valve with reversible switching and reverse circulation function, characterized in that: The utility model relates to a valve structure of reverse circulation drilling rig, which comprises an upper joint, a reverse circulation cylinder sleeve, a spring support sleeve, a circulating valve compression spring, a reverse circulation piston, a sealing packing, an intermediate joint, a valve plate compression spring, a valve plate push cylinder, a valve plate and a lower joint, one end of the reverse circulation cylinder sleeve is connected with the upper joint, the other end is connected with one end of the intermediate joint, the upper end of the reverse circulation cylinder sleeve is provided with the circulating valve compression spring and the spring support sleeve, the lower end of the reverse circulation cylinder sleeve is provided with the reverse circulation piston and the sealing packing, the other end of the intermediate joint is connected with one end of a valve plate cylinder sleeve, the other end of the valve plate cylinder sleeve is connected with the lower joint, the lower joint is provided with the valve plate in the middle part, is provided with the shear pin and the pin plug in the lower part, is provided with the valve plate compression spring and the valve plate push cylinder in the inside, the upper end surface of the spring support sleeve is provided with a thread, the bottom of the thread is provided with a cylindrical liquid inlet hole, the inside of the spring support sleeve is provided with a first sandproof internal hexagonal screw, the bottom of the first sandproof internal hexagonal screw is provided with uniformly distributed sand filtering holes, the liquid can enter the inside of the reverse circulation cylinder sleeve, the valve plate cylinder sleeve is provided with a plurality of uniformly distributed triangular screw holes in the middle and lower part of the circumference, the bottom of the triangular screw hole is provided with a small-diameter through hole, and the second sandproof internal hexagonal screw with sand filtering holes is arranged in the triangular screw hole.

2. The repeatedly openable and closeable anti-sand type temporary blocking valve with reverse circulation function according to claim 1, characterized in that: The lower end of the upper joint is connected with the upper end of the reverse circulation cylinder through a thread, and is sealed through a first O-shaped sealing ring, the middle and lower sections of the reverse circulation cylinder sleeve are provided with uniformly distributed waist-shaped grooves to provide a reverse circulation liquid flow channel, and the tail is connected with the external thread of the intermediate joint through a thread and is sealed through a second O-shaped sealing ring.

3. The repeatedly openable and closeable anti-sand type temporary blocking valve with reverse circulation function according to claim 1, characterized in that: The upper end surface of the circulating valve compression spring is in contact with the lower end surface of the upper step of the spring support sleeve, and the lower end surface of the spring support sleeve is in contact with the upper end surface of the reverse circulation piston.

4. The repeatedly openable and closeable anti-sand type temporary blocking valve with reverse circulation function according to claim 1, characterized in that: The third O-shaped sealing ring and the fourth O-shaped sealing ring are respectively arranged in the inner and outer wall sealing grooves of the upper end of the reverse circulation piston, and the middle and lower sections are in interference extrusion sealing with the inner wall of the sealing packing.

5. The switchable and anti-cycling sand control temporary plug valve with reverse circulation function according to claim 1, characterized in that: The fifth O-shaped sealing ring is arranged between the intermediate joint and the valve plate cylinder sleeve, and the sixth O-shaped sealing ring is arranged on the upper part of the valve plate push cylinder to be in sliding sealing with the inner wall of the valve plate cylinder sleeve.

6. The switchable and anti-cycling sand control temporary plug valve with reverse circulation function according to claim 1, characterized in that: The seventh O-shaped sealing ring is arranged between the valve plate cylinder sleeve and the lower joint, the eighth O-shaped sealing ring is arranged between the valve plate and the valve plate push cylinder, and the ninth O-shaped sealing ring is arranged between the valve plate and the lower joint.

7. The switchable and anti-cycling sand control temporary plug valve according to claim 1, characterized in that: The lower part of the lower joint is provided with a threaded hole, a pin plug and a tenth O-shaped sealing ring to be in travel cooperation sealing.

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