A new type of V-shaped precision micro-slit self-cleaning sand-proof short section

Abstract

The present invention relates to the technical field of oilfield development, and is a novel V-shaped precision micro-slit self-cleaning sand-proof short section, comprising a branch pipe, a plurality of through openings are provided on the pipe wall of the branch pipe in the axial direction, and a sand-proof shield is connected in each of the through openings, and an auxiliary mechanism for reducing sand grains blocking in the dead corner of the outer cover is provided in the sand-proof shield, and a micro-slit filtering mechanism for blocking mud and sand from entering the branch pipe is provided in the sand-proof shield, and a multi-stage filtering component for blocking mud and sand is provided in the sand-proof shield. The novel V-shaped precision micro-slit self-cleaning sand-proof short section, by providing an auxiliary component, makes it possible for the blocked sand grains to not form a blockage in the dead corner outside the sand-proof shield, thereby improving the self-unblocking ability of the branch pipe, and at the same time, by providing a micro-slit filtering mechanism, the effect of adjusting the inclination micro-slit gap angle is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of oilfield development, in particular to a novel V-shaped precision micro-slit self-cleaning sand-proof short joint. Background Art

[0002] At present, there are many methods for sand control in oil and gas wells. According to the principle of sand control, they can be roughly divided into sand arch sand control, chemical sand control, thermal coking sand control, mechanical sand control, composite sand control and other sand control methods. In the mechanical sand control process, sand control screens are usually used as sand control tools. During the production process of oil wells, the sand control screens are lowered into the wellbore of the oil well. When the surrounding formation fluid carries formation fine sand, mechanical impurities, clay, mud and other materials through the sand control screen, the particulate matter in the fluid is blocked by the sand control screen and separated outside, and the fluid flows to the ground through the sand control screen.

[0003] A V-shaped precision micro-slit self-cleaning sand-proof screen pipe was invented by publication number CN100335743C. The gap of the sand-proof unit of the V-shaped precision micro-slit self-cleaning sand-proof screen pipe is in the form of small outside and large inside, which prevents the filter pores from being blocked.

[0004] The disadvantage of the above-mentioned V-shaped precision micro-slit self-cleaning sand-proof screen pipe is that there are many notches on the surface of the outer cover of the filter element, which makes it easy for mud and sand to accumulate near the inside and outside of the notches, thereby accelerating the clogging of the screen pipe. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the shortcomings of the prior art, the present invention provides a new V-shaped precision micro-slit self-cleaning sand-proof short section, which has the ability of self-unblocking and can adapt to the filtration of different sand particle sizes, solving the problems that mud and sand are easily accumulated near its groove and the existing filter screen plate is not easy to adjust.

[0007] (II) Technical solution

[0008] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a novel V-shaped precision micro-slit self-cleaning sand-proof short section, comprising a branch pipe, a plurality of through openings are arranged on the pipe wall of the branch pipe in the axial direction, and a sand-proof protective cover is connected in each of the through openings, an auxiliary mechanism for reducing sand particles from blocking the dead corner of the outer cover is arranged in the sand-proof protective cover, a micro-slit filtering mechanism for blocking mud and sand from entering the branch pipe is arranged in the sand-proof protective cover, and a multi-stage filtering component for blocking mud and sand is arranged in the sand-proof protective cover;

[0009] The auxiliary mechanism changes the angle at which part of the fluid mixture contacts the auxiliary mechanism through the inclined micro-slit filtering mechanism, so that part of the fluid flushes the gravel on the surface of the micro-slit filtering mechanism;

[0010] The micro-gap filtering mechanism is used to filter gravel by setting an adjustable gap. At the same time, the gap of the micro-gap filtering mechanism, which is small outside and large inside, changes the flow rate of the fluid mixture, and cooperates with the auxiliary mechanism to flush the gravel.

[0011] Preferably, the auxiliary mechanism includes a slot arranged on the outer wall of the sand protection shield, the slot is inclined, the micro-slit filtering mechanism is parallel to the slot, a discharge port is provided on one side of the inner cavity of the sand protection shield, the discharge port is connected to the slot, and two groups of bosses are fixedly installed on the inner wall of the discharge port.

[0012] Preferably, the micro-gap filtering mechanism includes five groups of filter baffles and four hinged rods, the hinged rods are respectively arranged at the two ends of adjacent filter baffles, the hinged rods are composed of a first connecting rod and a second connecting rod, the first connecting rod and the second connecting rod are respectively rotatably connected to the two ends of adjacent filter baffles, wherein an inclined micro-gap gap with a small outside and a large inside is formed in the middle of two adjacent groups of filter baffles, the filter baffles are rotatably connected to the rotating rods, support plates are provided at both ends of the filter baffles, and both ends of the rotating rods are rotatably connected in the two groups of support plates.

[0013] Preferably, the micro-gap filtering mechanism includes five groups of filter baffles and four hinged rods, the hinged rods are respectively arranged at the two ends of adjacent filter baffles, the hinged rods are composed of a first connecting rod and a second connecting rod, the first connecting rod and the second connecting rod are respectively rotatably connected to the two ends of adjacent filter baffles, wherein an inclined micro-gap gap with a small outside and a large inside is formed in the middle of two adjacent groups of filter baffles, the filter baffles are rotatably connected to the rotating rods, support plates are provided at both ends of the filter baffles, and both ends of the rotating rods are rotatably connected in the two groups of support plates.

[0014] Preferably, the filter assembly includes supporting ball seats fixedly mounted at both ends of the inner cavity of the sand protection cover, and a wave plate is snap-connected to the supporting ball seat. Annular grooves are provided at both ends of the inner cavity of the slot, and filter screen plates are snap-connected in the annular grooves at both ends. The recessed portion of the wave plate is tightly attached to the outer surface of the filter screen plate, and a bridge-type gap is formed between the recessed portion of the wave plate and the outer surface of the filter screen plate.

[0015] Preferably, a compression groove is provided at the bottom end of the notch, a threaded hole is provided at one end of the compression groove, a screw is threadedly connected to the threaded hole, a wedge block is slidably connected to the compression groove, the screw is against the outer wall of the wedge block, a disc spring is fixedly installed at one end of the wedge block, a stop block is fixedly installed at one end of the disc spring, the stop block is against the outer wall of the sand control shield, a curved clamping portion is formed at one end of the sand control shield, a curved clamping portion is provided at one end of the notch to match the curved clamping portion, and the curved clamping portion is snap-connected in the curved clamping groove.

[0016] Preferably, the length of the micro-slit filtering mechanism is longer than the slot, and the micro-slit filtering mechanism abuts against the connection between the inner cavity of the sand control shield and the discharge port.

[0017] (III) Beneficial effects

[0018] Compared with the prior art, the present invention provides a new V-shaped precision micro-slit self-cleaning sand-proof short section, which has the following beneficial effects:

[0019] 1. By setting auxiliary components, during the production stage of the oil well, by setting an inclined notch in the sand protection cover, and making the micro-slit filtering mechanism and the notch in a parallel state, the sand-carrying oil entering the through port is in a downward inclined trend. When the sand-carrying oil passes through the micro-slit filtering mechanism, the sand particles that are not allowed to flow in are blocked under the action of the inclined micro-slit gap, and at the same time, these sand particles flow into the discharge port with the downward inclined trend, so that the blocked sand particles will not form blockages in the dead corner outside the sand protection cover as much as possible, thereby improving the self-unblocking ability of the branch pipe.

[0020] 2. By setting up a micro-gap filtering mechanism, the filter baffle on the outer wall of the rotating rod can be rotated by rotating the rotating rod, and the first connecting rod can be rotated on the second connecting rod through the linkage effect of the hinged rod. At the same time, the first connecting rod is rotated on the adjacent filter baffles on the second connecting rod, so that the angle between the adjacent filter baffles changes, thereby achieving the effect of adjusting the inclination micro-gap gap angle.

[0021] 3. By setting up a filter component, when the sand-carrying oil passes through the micro-slit filter mechanism and enters the filter component for filtration again, part of the sand-carrying oil first falls on the wave plate. Due to the wavy structure of the wave plate, part of the sand-carrying oil falls into the concave part of the wave plate. Through two filtrations, a sand bridge is formed between the concave part of the wave plate and the filter screen plate, which further assists in sand prevention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of the structure of a novel V-shaped precision micro-slit self-cleaning sand-control short section proposed by the present invention;

[0023] Figure 2 A partial cross-sectional schematic diagram of a new type of V-shaped precision micro-slit self-cleaning sand control short section middle branch pipe proposed by the present invention;

[0024] Figure 3 A cross-sectional schematic diagram of a novel V-shaped precision micro-slit self-cleaning sand-control short section provided by the present invention;

[0025] Figure 4 This is a schematic diagram of the structure of a novel V-shaped precision micro-slot self-cleaning sand-control pup joint micro-slot filtering mechanism proposed by the present invention;

[0026] Figure 5This is a schematic diagram of the structure of a new type of V-shaped precision micro-slit self-cleaning sand-proof short section with a wave plate;

[0027] Figure 6 This is an enlarged view of point a in a novel V-shaped precision micro-slit self-cleaning sand-control short section proposed by the present invention;

[0028] Figure 7 This is an enlarged view of point b in a new type of V-shaped precision micro-slit self-cleaning sand-proof short section proposed by the present invention.

[0029] In the figure: 1. branch pipe; 2. through port; 3. sand protection cover; 4. notch; 5. discharge port; 6. boss; 7. filter baffle; 8. first connecting rod; 9. second connecting rod; 10. inclined micro-gap; 11. rotating rod; 12. support plate; 13. spherical seat; 14. spherical slot; 15. bolt; 16. corrugated plate; 17. annular slot; 18. filter screen plate; 19. compression slot; 20. threaded hole; 21. screw; 22. wedge block; 23. disc spring; 24. stop block; 25. bent clamping part; 26. bent slot; 100. auxiliary mechanism; 101. micro-gap filtering mechanism; 102. filtering assembly; 200. supporting ball seat. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments 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 creative work are within the scope of protection of the present invention.

[0031] Embodiment 1:

[0032] See attached Figure 1-6A novel V-shaped precision micro-slit self-cleaning sand-proof short section comprises a branch pipe 1, a plurality of through-ports 2 are arranged on the pipe wall of the branch pipe 1 in the axial direction, a sand-proof shield 3 is connected in each through-port 2, an auxiliary mechanism 100 is arranged in the sand-proof shield 3 for reducing the blockage of sand particles in the dead corner of the outer shield, the auxiliary mechanism 100 comprises a notch 4 arranged on the outer wall of the sand-proof shield 3, the notch 4 has a large area, so that the flow area is increased, the notch 4 is inclined, and the inclination angle of the notch 4 can be 10° to 20°, which can be adjusted according to actual conditions, the micro-slit filtering mechanism 101 is parallel to the notch 4, and the micro-slit filtering mechanism 101 is parallel to the notch 4, so that when the sand-carrying oil flows to the micro-slit filtering mechanism 101, the inflow direction is inclined Slanting downward, the sand-carrying oil enters the micro-slit filtering mechanism 101 along the inclined micro-slit gap 10, and the unauthorized sand particles move downward along the inclined micro-slit gap 10 until they flow into the discharge port 5. A discharge port 5 is provided on the left side of the inner cavity of the sand-control shield 3, and the discharge port 5 is connected to the slot 4. Two groups of bosses 6 are fixedly installed on the inner wall of the discharge port 5. By setting the boss 6, when part of the sand-carrying oil falls on the boss 6, the arc section of the boss 6 allows the sand-carrying oil to flow into the micro-slit filtering mechanism 101 again. The length of the micro-slit filtering mechanism 101 is longer than the slot 4, so that the micro-slit filtering mechanism 101 has a better filtering effect on the sand-carrying oil, and the micro-slit filtering mechanism 101 is against the connection between the inner cavity of the sand-control shield 3 and the discharge port 5.

[0033] The auxiliary mechanism 100 changes the angle at which part of the fluid mixture contacts the auxiliary mechanism 100 through the inclined micro-slit filtering mechanism 101, so that part of the fluid flushes the gravel on the surface of the micro-slit filtering mechanism 101. The micro-slit filtering mechanism 101 is used to filter the gravel by setting an adjustable gap. At the same time, the gap of the micro-slit filtering mechanism 101, which is small on the outside and large on the inside, changes the flow rate of the fluid mixture, cooperating with the auxiliary mechanism 100 to flush the gravel.

[0034] In the present embodiment, during the production stage of the oil well, an inclined notch 4 is provided in the sand-proof protective cover 3, and the micro-slit filtering mechanism 101 is parallel to the notch 4, so that the sand-carrying oil entering the through port 2 is in a downwardly inclined trend. When the sand-carrying oil passes through the micro-slit filtering mechanism 101, the sand particles that are not allowed to flow in are blocked under the action of the inclined micro-slit gap 10, and these sand particles flow into the discharge port 5 with the downwardly inclined trend. At the same time, two groups of bosses 6 are provided in the discharge port 5, so that the sand-carrying oil flows to the micro-slit filtering mechanism 101 again under the action of the arc-shaped part of the boss 6, and the sand particles in part of the sand-carrying oil are filtered again. Finally, the sand particles are discharged from the curved section at the lower end of the discharge port 5, and the sand particles filtered by the inclined micro-slit gap 10 flow into the filter assembly 102 for filtering again, so that the blocked sand particles will not form blockage in the dead corner outside the sand-proof protective cover 3 as much as possible, and the self-cleaning function is provided, thereby improving the self-unblocking ability of the branch pipe 1.

[0035] Embodiment 2: Based on embodiment 1, the difference is that;

[0036] See attached Figure 2-7 The sand-proof shield 3 is provided with a micro-slit filtering mechanism 101 for preventing mud and sand from entering the branch pipe 1. The micro-slit filtering mechanism 101 includes five groups of filtering baffles 7 and four hinged rods. The hinged rods are respectively arranged at the two ends of adjacent filtering baffles 7. The hinged rods are composed of a first connecting rod 8 and a second connecting rod 9. The first connecting rod 8 and the second connecting rod 9 are respectively connected to the two ends of adjacent filtering baffles 7 through bearings, wherein a micro-slit gap 10 with a small outside and a large inside is formed in the middle of two adjacent groups of filtering baffles 7. The filtering baffles 7 are all connected to rotating rods 11 in rotation. Support plates 12 are provided at both ends of the filtering baffles 7. Both ends of the rotating rod 11 are rotatably connected in the two groups of supporting plates 12. By rotating the rotating rod 11, the gap of the inclined micro-slit gap 10 can be adjusted, so that the inclined micro-slit gap 10 is easy to adapt to different working conditions.

[0037] Two spherical seats 13 are fixedly installed on the support plate 12, and spherical grooves 14 corresponding to the spherical seats 13 are provided at both ends of the inner cavity of the sand protection cover 3. The spherical seats 13 are correspondingly engaged in the spherical grooves 14. By setting the spherical seats 13 and the spherical grooves 14, it is convenient to install the micro-slit filtering mechanism 101. Two groups of bolts 15 are fixedly installed on the outer wall of the support plate 12, and the bolts 15 are correspondingly pressed against the outer wall of the filter baffle 7. The support plate 12 and the filter baffle 7 are fixed by the bolts 15, which is convenient for fixing the gap of the inclined micro-slit gap 10.

[0038] The micro-slit filtering mechanism 101 provided in the present invention can be easily installed through the two groups of spherical seats 13 on the support plate 12 when in use. At the same time, before installation, the filter baffle 7 on the outer wall of the rotating rod 11 can be rotated by rotating the rotating rod 11, and the first connecting rod 8 can be rotated on the second connecting rod 9 through the linkage effect of the hinged rod. At the same time, the first connecting rod 8 rotates on the second connecting rod 9 respectively on the adjacent filter baffles 7, so that the angle between the adjacent filter baffles 7 changes, thereby achieving the effect of adjusting the angle of the inclined micro-slit gap 10. In this way, during the production of the oil well, when the sand-carrying oil flows into the micro-slit filtering mechanism 101, the inclined micro-slit gap 10 blocks the sand particles of different sizes in the sand-carrying oil, thereby improving the oil recovery effect.

[0039] Embodiment 3: Based on embodiment 1, the difference is that;

[0040] See attached Figure 2-7A multi-stage filter assembly 102 for blocking mud and sand is provided in the sand control shield 3. The filter assembly 102 includes a support ball seat 200 fixedly mounted at both ends of the inner cavity of the sand control shield 3. A wave plate 16 is snap-connected to the support ball seat 200. By setting the support ball seat 200, it is convenient to install the wave plate 16. An annular groove 17 is provided at both ends of the inner cavity of the slot 4. The filter screen plate 18 is snap-connected in the annular grooves 17 at both ends. The concave portion of the wave plate 16 is tightly attached to the outer surface of the filter screen plate 18, and a bridge-type gap is formed between the concave portion of the wave plate 16 and the outer surface of the filter screen plate 18. The concave portion of the wave plate 16 is provided with two groups of filter holes, and the two groups of filter holes form a bridge-type gap with the outer surface of the filter screen plate 18. The bridge-type gap is a prior art and is not repeated in this scheme to further improve the sand control effect.

[0041] A compression groove 19 is provided at the bottom end of the notch 4, and a threaded hole 20 is provided at the left end of the compression groove 19. A screw rod 21 is connected to the inner thread of the threaded hole 20. A wedge block 22 is slidably connected in the compression groove 19, and the screw rod 21 abuts against the outer wall of the wedge block 22. A disc spring 23 is fixedly installed at the lower end of the wedge block 22, and a block 24 is fixedly installed at the upper end of the disc spring 23. The block 24 abuts against the outer wall of the sand control shield 3. A curved clamping portion 25 is formed at the upper end of the sand control shield 3. A curved clamping groove 26 matching the curved clamping portion 25 is provided at the upper end of the notch 4, and the curved clamping portion 25 is snap-connected in the curved clamping groove 26. By arranging the above components, it is convenient to install the sand control shield 3.

[0042] The present invention is provided with a filter assembly 102. When the sand-carrying oil is filtered by the micro-slit filter mechanism 101 and then enters the filter assembly 102 for filtration again, part of the sand-carrying oil first falls on the wave plate 16. Due to the wavy structure of the wave plate 16, part of the sand-carrying oil falls into the concave part of the wave plate 16. Through two filtrations, a sand bridge is formed between the concave part of the wave plate 16 and the filter screen plate 18, which further assists in sand prevention.

[0043] When installing the sand shield 3, first place the sand shield 3 in an inclined manner into the through opening 2, then engage the bent clamping portion 25 of the sand shield 3 with the bent clamping groove 26, and then turn the screw 21 into the threaded hole 20. When the screw 21 moves downward, it contacts the inclined section of the wedge block 22, causing the wedge block 22 to move upward. At this time, the spring force generated by the elastic disc spring 23 squeezes the stop block 24, thereby fixing the sand shield 3.

[0044] It should be noted that the term "comprises" or any other variation thereof is intended to cover non-exclusive inclusion, so that a process, method, article, or device that includes a series of elements includes not only those elements, but also includes other elements that are not explicitly listed, or also includes elements inherent to such process, method, article, or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article, or device that includes the element.

[0045] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A novel V-shaped precision micro-slit self-cleaning sand control short section, comprising a branch pipe (1), characterized in that: A plurality of groups of through openings (2) are provided on the pipe wall of the branch pipe (1) in the axial direction, and a sand-proof shield (3) is snap-fitted and connected in each of the through openings (2). An auxiliary mechanism (100) is provided in the sand-proof shield (3), and a micro-slit filtering mechanism (101) is provided in the sand-proof shield (3). A filtering assembly (102) is provided in the sand-proof shield (3); The auxiliary mechanism (100) comprises a notch (4) arranged on the outer wall of the sand protection cover (3), the notch (4) is inclined, the micro-slit filtering mechanism (101) is parallel to the notch (4), a discharge port (5) is arranged on one side of the inner cavity of the sand protection cover (3), the discharge port (5) is connected to the notch (4), and two groups of bosses (6) are fixedly mounted on the inner wall of the discharge port (5), and the auxiliary mechanism (100) changes the angle at which a part of the fluid mixture contacts the auxiliary mechanism (100) through the inclined micro-slit filtering mechanism (101), so that a part of the fluid flushes the sand and gravel on the surface of the micro-slit filtering mechanism (101); The micro-slit filtering mechanism (101) comprises five groups of filtering baffles (7) and four hinged rods, wherein the hinged rods are respectively arranged at the two ends of adjacent filtering baffles (7), and the hinged rods are composed of a first connecting rod (8) and a second connecting rod (9), wherein the first connecting rod (8) and the second connecting rod (9) are respectively rotatably connected to the two ends of adjacent filtering baffles (7), wherein a micro-slit gap (10) with an inclination that is small on the outside and large on the inside is formed in the middle of two adjacent groups of filtering baffles (7), wherein the filtering baffles (7) are both rotatably connected to a rotating rod (11), and support plates (12) are respectively arranged at the two ends of the filtering baffles (7), and the two ends of the rotating rod (11) are both rotatably connected in the two groups of support plates (12), and the micro-slit filtering mechanism (101) is used for filtering sand and gravel by setting an adjustable gap, and at the same time, the gap of the micro-slit filtering mechanism (101) that is small on the outside and large on the inside changes the flow rate of the fluid mixture, and cooperates with the auxiliary mechanism (100) to flush the sand and gravel.

2. According to claim 1, a novel V-shaped precision micro-slit self-cleaning sand-proof short section is characterized by: A compression groove (19) is provided at the bottom end of the notch (4), a threaded hole (20) is provided at one end of the compression groove (19), a screw rod (21) is connected to the inner thread of the threaded hole (20), a wedge block (22) is slidably connected in the compression groove (19), the screw rod (21) abuts against the outer wall of the wedge block (22), a disc spring (23) is fixedly installed at one end of the wedge block (22), a stop block (24) is fixedly installed at one end of the disc spring (23), the stop block (24) abuts against the outer wall of the sand control shield (3), a curved clamping portion (25) is formed at one end of the sand control shield (3), a curved clamping groove (26) matching the curved clamping portion (25) is provided at one end of the notch (4), and the curved clamping portion (25) is snap-fitted into the curved clamping groove (26).

3. According to claim 1, a novel V-shaped precision micro-slit self-cleaning sand-proof short section is characterized by: The length of the micro-slit filtering mechanism (101) is longer than the notch (4), and the micro-slit filtering mechanism (101) abuts against the connection between the inner cavity of the sand control shield (3) and the discharge port (5).

4. According to claim 1, the novel V-shaped precision micro-slit self-cleaning sand-proof short section is characterized by: The filter assembly (102) includes a support ball seat (200) fixedly mounted at both ends of the inner cavity of the sand protection cover (3), a wave plate (16) is snap-connected to the support ball seat (200), an annular groove (17) is provided at both ends of the inner cavity of the slot (4), and a filter screen plate (18) is snap-connected in the annular groove (17) at both ends, the concave portion of the wave plate (16) is tightly attached to the outer surface of the filter screen plate (18), and a bridge-type gap is formed between the concave portion of the wave plate (16) and the outer surface of the filter screen plate (18).

5. According to claim 1, the novel V-shaped precision micro-slit self-cleaning sand-proof short section is characterized by: Two spherical seats (13) are fixedly mounted on the support plate (12); spherical slots (14) corresponding to the spherical seats (13) are provided at both ends of the inner cavity of the sand protection cover (3); the spherical seats (13) are correspondingly engaged in the spherical slots (14); two groups of bolts (15) are fixedly mounted on the outer wall of the support plate (12); the bolts (15) are correspondingly pressed against the outer wall of the filter baffle (7).

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