Packer for oil well

Abstract

The utility model provides a packer for an oil well, which comprises a plurality of slips uniformly arranged along the circumferential direction of a mandrel, two cones arranged at two ends of the slips, a limit sleeve sleeved outside the slips, a plurality of through holes arranged on the limit sleeve and matched with the slips, and a return spring arranged between the slips and the limit sleeve. The cleaning assembly comprises a plurality of cleaning brushes arranged in the length direction of the slips, the cleaning brushes are arranged on the outer sides of the limiting sleeves, connecting sleeves are arranged at the two ends of each cleaning brush and rotationally connected with the limiting sleeves, the positions and the number of the cleaning brushes correspond to those of the slips one to one, and torsional springs used for driving the cleaning brushes to rotate along the outer wall faces of the slips are arranged between the connecting sleeves and the limiting sleeves. And the torsion spring is also provided with a locking mechanism which is used for compressing the torsion spring before setting and releasing the torsion spring during setting. According to the packer for the oil well, when the cleaning brush is used for setting the packer, solid-phase particles between the slip and the sleeve are cleaned, it is guaranteed that when the slip is opened in the radial direction, the slip can cling to the inner wall face of the sleeve, and normal setting of the packer is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of packers, in particular to a packer for oil wells. Background Art

[0002] A packer is a downhole tool with elastic sealing elements that can be used to seal the annular space between tubings of various sizes and the wellbore, as well as between tubings, and to isolate the production layer, thereby controlling fluid production and protecting the casing.

[0003] During the use of the packer, the packer is lowered into the casing in the well. Due to the long lowering time of the casing, the high specific gravity and easy precipitation of the well fluid, and the large amount of solid additives in the well fluid, after the packer is sent to the sealing position, there are often many solid particles between the slips and the casing. When the slips are radially expanded, they cannot bite the casing tightly, resulting in the failure of the packer to seal, affecting the normal use of the packer. Summary of the invention

[0004] The technical problem to be solved by the utility model is: in order to overcome the shortcomings of the prior art in which the packer is lowered into the casing in the well during use, due to the long casing lowering time, the high specific gravity of the well fluid and the easy precipitation, and the large amount of solid phase additives in the well fluid, which often leads to a large amount of solid phase particles between the slips and the casing after the packer is sent to the sealing position, and the slips cannot bite the casing when they are radially expanded, thereby causing the packer to fail to seal and affecting the normal use of the packer. The utility model provides a packer for oil wells.

[0005] The technical solution to be adopted by the utility model to solve its technical problems is: a packer for oil wells, comprising a plurality of slips evenly arranged along the circumference of a core shaft, two cones for driving the slips to radially open the inner wall surface of the engaging casing are arranged at both ends of the slips, a limiting sleeve is arranged on the outer sleeve of the slips, a plurality of through holes cooperating with the slips are arranged on the limiting sleeves, a reset spring is arranged between the slips and the limiting sleeves, and also comprises a cleaning component, the cleaning component comprises a plurality of cleaning brushes arranged along the length direction of the slips, the cleaning brushes are arranged on the outer side of the limiting sleeves, connecting sleeves are arranged at both ends of the cleaning brushes, the connecting sleeves are rotatably connected with the limiting sleeves, the positions and quantities of the cleaning brushes correspond one to one with the slips, a torsion spring for driving the cleaning brush to rotate along the outer wall surface of the slips is arranged between the connecting sleeves and the limiting sleeves, and a locking mechanism for compressing the torsion spring before sealing and releasing the torsion spring when sealing is also arranged on the torsion spring.

[0006] A cleaning brush is provided on one side of each slip, and all cleaning brushes are connected to the connecting sleeve. A torsion spring is provided between the connecting sleeve and the limit sleeve. Before sealing, the locking mechanism fixes the torsion spring in a compressed state; when sealing, the two cones are close to each other, the locking mechanism releases the fixation of the torsion spring, and the torsion spring drives the cleaning brush to rotate along the outer wall of the slip, scraping away the solid particles between the outer wall of the slip and the inner wall of the casing, ensuring that the slip can bite the inner wall of the casing when the slip is radially expanded.

[0007] Furthermore, the working surface of the cleaning brush is tooth-shaped and matches with the outer wall surface of the slip. Before the packer seat is sealed, the cleaning brush is arranged on one side of the slip and matches with the slip gap.

[0008] Furthermore, in order to unlock the torsion spring when the packer is sealed so that the cleaning brush can scrape away the solid particles between the outer wall of the cava and the inner wall of the casing, the locking mechanism includes a plurality of limit rods, the middle position of the limit rods is rotatably connected to the side wall of the through hole, the upper end of the limit rods corresponds to the outermost tooth position at both ends of the cleaning brush, the lower end of the limit rods is abutted against the conical surface of the cone, and the limit rod is arranged between the cava and the cleaning brush before the packer is sealed.

[0009] Before sealing, a limit rod is arranged between the cleaning brush and the slip, so that the torsion spring is in a compressed state. When sealing, the two cones approach each other, and the cones push the limit rod to rotate along the rotation center, so that the limit rod avoids the cleaning brush. After the cleaning brush is freed from restraint, it rotates along the outer wall of the slip under the drive of the torsion spring, and scrapes away the solid particles between the outer wall of the slip and the inner wall of the casing.

[0010] Furthermore, in order to prevent the cleaning brush from being within the radially expanded range of the slips after cleaning the solid particles, thereby interfering with the expansion of the slips, four slips are evenly arranged around the core shaft, and the rotation angle of the cleaning brush is not greater than 90°.

[0011] Furthermore, a plurality of limit blocks for limiting the rotation angle of the cleaning brush are provided on the outer wall surface of the limit sleeve in the circumferential direction, and the positions and numbers of the limit blocks correspond to the cleaning brushes one by one.

[0012] The beneficial effects of the utility model are as follows: the utility model provides an oil well packer, which uses a cleaning brush to clean solid particles between the slips and the casing when the packer is seated, ensuring that the slips can bite the inner wall of the casing when the slips are radially expanded, thereby ensuring that the packer is normally seated. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0014] Figure 1 It is a structural schematic diagram of the best embodiment of the utility model;

[0015] Figure 2 It is a cross-sectional schematic diagram of the best embodiment of the utility model.

[0016] In the figure: 1, slip, 2, cone, 3, limit sleeve, 301, through hole, 4, reset spring, 5, cleaning brush, 6, connecting sleeve, 7, torsion spring, 8, limit rod, 9, limit block. DETAILED DESCRIPTION

[0017] Now the utility model is described in detail with reference to the accompanying drawings. This figure is a simplified schematic diagram, which only illustrates the basic structure of the utility model in a schematic manner, so it only shows the components related to the utility model.

[0018] like Figure 1-2 As shown, the utility model is a packer for oil wells, comprising a plurality of slips 1 uniformly arranged along the circumference of the core shaft, two cones 2 for driving the slips 1 to radially open the inner wall of the engaging casing are provided at both ends of the slips 1, a limiting sleeve 3 is provided on the outer side of the slips 1, a plurality of through holes 301 cooperating with the slips 1 are provided on the limiting sleeve 3, a reset spring 4 is provided between the slips 1 and the limiting sleeve 3, and also comprises a cleaning assembly, the cleaning assembly comprises a plurality of cleaning brushes 5 arranged along the length direction of the slips 1, the cleaning brushes 5 are arranged on the outer side of the limiting sleeve 3, connecting sleeves 6 are provided at both ends of the cleaning brushes 5, the connecting sleeves 6 are rotatably connected with the limiting sleeve 3, the positions and the numbers of the cleaning brushes 5 correspond one to one with the slips 1, a torsion spring 7 for driving the cleaning brush 5 to rotate along the outer wall of the slips 1 is provided between the connecting sleeve 6 and the limiting sleeve 3, and a locking mechanism for compressing the torsion spring 7 before sealing and releasing the torsion spring 7 when sealing is also provided on the torsion spring 7.

[0019] The working surface of the cleaning brush 5 is tooth-shaped and matches with the outer wall of the slip 1 . Before the packer seat is sealed, the cleaning brush 5 is arranged on one side of the slip 1 and matches with the slip 1 in a clearance.

[0020] The locking mechanism includes multiple limit rods 8, the middle position of the limit rod 8 is rotatably connected to the side wall of the through hole 301, the upper end of the limit rod 8 corresponds to the outermost tooth position at both ends of the cleaning brush 5, the lower end of the limit rod 8 is abutted against the conical surface of the cone 2, and the limit rod 8 before the sealing of the packer seat is arranged between the cava 1 and the cleaning brush 5.

[0021] Four slips 1 are evenly arranged on the circumference of the core shaft, and the rotation angle of the cleaning brush 5 is not greater than 90°.

[0022] A plurality of limit blocks 9 for limiting the rotation angle of the cleaning brush 5 are arranged on the outer wall surface of the limit sleeve 3 along the circumferential direction, and the positions and numbers of the limit blocks 9 correspond to the cleaning brush 5 one by one.

[0023] Working process:

[0024] Before sealing, the limit rod 8 is arranged between the cleaning brush and the slip 1, and the torsion spring 7 is in a compressed state; when sealing, the two cones 2 approach each other, and the cone 2 pushes the lower end of the limit rod 8 to make the limit rod 8 rotate along the rotation center. During the rotation of the upper end of the limit rod 8, the outermost teeth at both ends of the cleaning brush 5 are staggered. After losing the restraint of the limit rod 8, the cleaning brush 5 rotates along the outer wall of the slip 1 driven by the torsion spring 7 to scrape away the solid particles between the outer wall of the slip 1 and the inner wall of the sleeve. The cleaning brush 5 stops rotating after hitting the limit rod 8 on the limit sleeve 3, and the two cones 2 continue to squeeze the slip 1, and the slip 1 is radially expanded to bite the inner wall of the sleeve.

[0025] Directions and references (e.g., up, down, left, right, etc.) in the present invention may only be used to assist in the description of features in the accompanying drawings. Therefore, the following detailed description is not to be taken in a limiting sense, and the scope of the subject matter claimed is limited only by the attached claims and their equivalents.

[0026] Based on the above ideal embodiments of the utility model, the relevant staff can make various changes and modifications without departing from the scope of the utility model through the above description. The technical scope of this utility model is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A packer for oil wells, comprising a plurality of slips (1) uniformly arranged along the circumference of a core shaft, wherein two ends of the slips (1) are provided with two cones (2) for driving the slips (1) to radially open the inner wall surface of the engaging casing, wherein: The outer sleeve of the slip (1) is provided with a limiting sleeve (3), the limiting sleeve (3) is provided with a plurality of through holes (301) cooperating with the slip (1), a reset spring (4) is provided between the slip (1) and the limiting sleeve (3), and a cleaning assembly is also included, the cleaning assembly comprises a plurality of cleaning brushes (5) arranged along the length direction of the slip (1), the cleaning brushes (5) are arranged on the outer side of the limiting sleeve (3), connecting sleeves (6) are provided at both ends of the cleaning brushes (5), the connecting sleeves (6) are rotatably connected to the limiting sleeve (3), the positions and numbers of the cleaning brushes (5) correspond to the slip (1), a torsion spring (7) is provided between the connecting sleeve (6) and the limiting sleeve (3) for driving the cleaning brush (5) to rotate along the outer wall surface of the slip (1), and a locking mechanism is also provided on the torsion spring (7) for compressing the torsion spring (7) before sealing and releasing the torsion spring (7) when sealing.

2. An oil well packer according to claim 1, characterized in that: The working surface of the cleaning brush (5) is tooth-shaped and matches the outer wall surface of the slip (1). Before the packer seat is sealed, the cleaning brush (5) is arranged on one side of the slip (1) and matches the slip (1) with a gap.

3. An oil well packer as claimed in claim 2, characterized in that: The locking mechanism comprises a plurality of limit rods (8), wherein the middle position of the limit rod (8) is rotatably connected to the side wall of the through hole (301), the upper end of the limit rod (8) corresponds to the outermost tooth position of the two ends of the cleaning brush (5), the lower end of the limit rod (8) is abutted against the conical surface of the cone (2), and the limit rod (8) before the packer seat is sealed is arranged between the slip (1) and the cleaning brush (5).

4. The oil well packer according to claim 1, characterized in that: Four slips (1) are evenly arranged around the mandrel, and the cleaning brush (5) has a rotation angle of no more than 90°.

5. The oil well packer according to claim 4, characterized in that: A plurality of limit blocks (9) for limiting the rotation angle of the cleaning brush (5) are provided on the outer wall surface of the limit sleeve (3) in the circumferential direction, and the positions and numbers of the limit blocks (9) correspond one to one with the cleaning brush (5).

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