Patch type slip structure for anchoring high-strength casing of oil-water well

Abstract

The invention discloses a patch type slip structure for anchoring a high-strength casing of an oil-water well. The problems that an existing integrated slip is not firm in anchoring with a casing due to insufficient strength, and the cost is increased due to the fact that the slip is easy to break are mainly solved. The slip is characterized in that two slip grooves (11) are formed in the slip base body (1), the slips (2) are arranged in the slip grooves (11) respectively, and a spring piece (6) is connected to the side, opposite to the slips (2), of the slip base body (1). According to the patch type slip structure for anchoring the high-strength casing pipe of the oil-water well, the slip base body and the slip are separately machined, machining is convenient, cost is reduced, and the strength of the slip is improved so that the slip can not be broken easily.

Description

Technical Field

[0001] The invention relates to the technical field of downhole tools in oil and gas fields, in particular to a patch-type slip structure used for anchoring high-strength casings in oil and water wells. Background Art

[0002] In downhole operations such as stratified injection and fracturing, the ability of the packer slip to anchor the casing determines the packer's setting effect, thus affecting the success or failure of the overall process. The traditional one-piece slip has a single structure, and the entire slip is processed using the same alloy material. When it is necessary to anchor high-strength casing, the slip is not strong enough, which can easily cause the anchoring between the slip and the casing to be loose; if it is processed with a stronger material, the processing difficulty will increase. Moreover, due to the poor plasticity of this type of material, the slip is prone to breakage during the anchoring process, which will also greatly increase the cost. Summary of the invention

[0003] In order to overcome the problem that the existing one-piece slips are not strong enough, resulting in loose anchoring with the casing and easy breakage of the slips, which leads to increased costs, the present invention provides a patch-type slip structure for high-strength casing anchoring of oil and water wells. In the patch-type slip structure for high-strength casing anchoring of oil and water wells, the slip base and the slip are processed separately, which is convenient to process and reduces costs, and the strength of the slip is increased to make it less likely to break.

[0004] The technical solution of the present invention is: a patch-type slip structure for high-strength casing anchoring in oil and water wells, comprising a slip base, two slip grooves are formed on the slip base, slips are respectively arranged in the slip grooves, and a spring sheet is connected to the side of the slip base opposite to the slip.

[0005] A plurality of fixed tooth slots are provided on the bottom surface of the slip groove, and fixed teeth are provided on the slip matching surface of the slip, and the fixed teeth match with the fixed tooth slots.

[0006] The slip groove is a dovetail groove.

[0007] The fixed tooth slot is a dovetail slot.

[0008] The fixed tooth groove is a V-shaped groove, and the V-shaped grooves of the left and right slip grooves are in opposite directions, and the side inclination angle of one side inside the V-shaped groove is smaller than the side inclination angle of the outside.

[0009] A spring sheet groove is provided in the middle of the side of the slip base opposite to the slip groove, the spring sheet is located in the spring sheet groove, and the spring sheet is fixed on the slip base through a slip pin.

[0010] The slip base is located outside the central tube and is bent along the outer surface of the central tube. The spring sheet is arc-shaped along the radial direction of the central tube, and the curvature of the spring sheet is greater than that of the slip base.

[0011] An upper cone and a lower cone are respectively arranged between the two ends of the slip base and the central tube, and the upper cone and the lower cone are matched with the slip base through cone surfaces.

[0012] The outer parts of the upper cone and the lower cone are respectively connected to the working cylinder through seat clamp pins.

[0013] The present invention has the following beneficial effects: due to the adoption of the above scheme, the slips are connected to the slip base body by interference fit, the slips are completely confined in the grooves, there are no openings, and they are not fixed by screws, so it is not easy for the local stress to be too large and break. The anchoring process is completely applied to the slips made of high-strength materials, and the bearing capacity of the slip base body is small and not easy to be damaged. A slip base body contains two groups of slip grooves, and a pair of bidirectional slips can be installed. The double-cone bidirectional slip anchoring mechanism adopted can effectively improve the anchoring effect of the casing. This patch-type structure is easy to install and disassemble. When it is necessary to anchor a higher-strength casing, only the high-strength slip material needs to be partially replaced, and the overall cost will not be increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 It is the main view of the kava matrix; Figure 3 It is a top view of the kava matrix; Figure 4 It is a radial cross-sectional view of the kava matrix; Figure 5 This is the front view of the Kavaya.

[0015] In the figure, 1-slip base, 2-slip teeth, 3-slip pin, 4-slip hanging, 5-upper cone, 6-spring leaf, 7-center tube, 8-lower cone, 9-seat pin, 11-slip groove, 12-fixed tooth groove, 13-slip pin hole, 14-spring leaf groove, 21-slip matching surface, 22-fixed tooth, 23-slip teeth. Implementation

[0016] The present invention will be further described below in conjunction with the accompanying drawings: Depend on Figures 1 to 5As shown, a patch-type slip structure for anchoring high-strength casing of oil and water wells includes a slip base 1, on which two slip grooves 11 are formed, and the slip grooves 11 are dovetail grooves, and both sides of each slip groove 11 are inclined surfaces. Slips 2 are respectively arranged in the slip grooves 11, and both sides of the slip 2 are inclined surfaces that match the slip grooves 11. Interference fit is adopted between the slip 2 and the slip base 1, so that the slip 2 is completely confined in the slip groove 11. A plurality of fixed tooth grooves 12 are formed on the bottom surface of the slip groove 11, and the fixed tooth grooves 12 can be dovetail grooves or V-shaped grooves. When the fixed tooth grooves 12 are V-shaped grooves, the V-shaped grooves of the left and right slip grooves 11 are opposite, and the side inclination angle of one side of the inner side of the V-shaped groove is smaller than the side inclination angle of the outer side. A fixed tooth 22 is provided on the slip matching surface 21 of the slip 2, and the fixed tooth 22 matches the fixed tooth groove 12. The side of the slip 2 opposite to the slip mating surface 21 is composed of a number of evenly distributed slip teeth 22, and the parameters such as tooth inclination angle, tooth shape angle, and tooth spacing can be designed according to actual requirements. The slip 2 is attached to the slip base 1 in a sheet shape. Since the slip 2 and the slip base 1 are separate structures, the slip base 1 and the slip 2 can be made of different alloy materials. The slip base 1 generally uses commonly used medium-strength steel materials to maintain certain toughness, plasticity and wear resistance. The slip 2 can be made of high-strength steel materials according to the strength of the casing to be anchored. When it is necessary to anchor a casing with greater strength, only the high-strength slip 2 material needs to be partially replaced, and the overall cost will not be increased.

[0017] A spring sheet groove 14 is provided in the middle of the side opposite to the slip 2 on the slip base 1, and a spring sheet 6 is connected to the spring sheet groove 14 through a slip pin 3. The slip base 1 is located outside the central tube 7, and the slip base 1 is bent along the outer surface of the central tube 7, and the spring sheet 6 is also arc-shaped along the radial direction of the central tube 7, and the curvature of the spring sheet 6 is greater than that of the slip base 1.

[0018] The two ends of the slip body 1 on one side of the spring sheet groove 14 are conical surfaces, and an upper cone 5 and a lower cone 8 are respectively arranged between the conical surfaces on both sides and the central tube 7, and the upper cone 5 and the lower cone 8 are respectively matched with the slip body 1 through inclined surfaces. The outer parts of the upper cone 5 and the lower cone 8 are respectively connected to the working cylinder through the seat pin 9.

[0019] The slip structure has four evenly distributed on the slip hanger 4 of a packer, a pair of bidirectional slips 2 are installed on a slip base 1, and the center pipe 7 supports the entire slip structure. After the packer is installed, the tool is lowered to set the seal. Hydraulic pressure is added from the oil pipe, and the setting pin is sheared after reaching a certain pressure. The piston pushes the slip hanger 4 downward, and the setting pin 9 connected to the lower cone 8 at the bottom is sheared off. The slip extends out under the pressure of the upper cone 5 and the lower cone 8. When the slip hanger 4 moves to the lower joint, the setting pin 9 connected to the upper cone 5 at the top is sheared off, and the upper cone 5 continues to move downward until the slip is completely anchored to the casing.

Claims

1. A patch-type slip structure for high-strength casing anchoring in oil and water wells, comprising a slip base (1), characterized in that: The slip base (1) is provided with two slip grooves (11), each of which contains a slip (2). A spring sheet (6) is connected to the side of the slip base (1) opposite to the slip (2).

2. The patch-type slip structure for high-strength casing anchoring in oil and water wells according to claim 1 is characterized in that: A plurality of fixed tooth slots (12) are formed on the bottom surface of the cava groove (11), and fixed teeth (22) are provided on the cava mating surface (21) of the cava (2), wherein the fixed teeth (22) are mated with the fixed tooth slots (12).

3. The patch-type slip structure for high-strength casing anchoring in oil and water wells according to claim 2 is characterized in that: The slip groove (11) is a dovetail groove.

4. The patch-type slip structure for high-strength casing anchoring in oil and water wells according to claim 3 is characterized in that: The fixed tooth slot (12) is a dovetail slot.

5. The patch-type slip structure for high-strength casing anchoring in oil and water wells according to claim 3 is characterized in that: The fixed tooth groove (12) is a V-shaped groove, and the V-shaped grooves of the left and right slip grooves (11) are in opposite directions, and the side inclination angle of one side inside the V-shaped groove is smaller than the side inclination angle of the outside.

6. The patch-type slip structure for high-strength casing anchoring in oil and water wells according to claim 1 is characterized in that: A spring sheet groove (14) is provided in the middle of the side of the slip base (1) opposite to the slip groove (11), the spring sheet (6) is located in the spring sheet groove (14), and the spring sheet (6) is fixed to the slip base (1) via a slip pin (3).

7. The patch-type slip structure for high-strength casing anchoring in oil and water wells according to claim 1 is characterized in that: The cava base (1) is located outside the central tube (7), and the cava base (1) is bent along the outer surface of the central tube (7), the spring sheet (6) is arc-shaped along the radial direction of the central tube (7), and the curvature of the spring sheet (6) is greater than the curvature of the cava base (1).

8. The patch-type slip structure for high-strength casing anchoring in oil and water wells according to claim 7 is characterized in that: An upper cone (5) and a lower cone (8) are respectively provided between the two ends of the cava base (1) and the central tube (7), and the upper cone (5) and the lower cone (8) are respectively matched with the cava base (1) via conical surfaces.

9. The patch-type slip structure for high-strength casing anchoring in oil and water wells according to claim 8 is characterized in that: The exteriors of the upper cone (5) and the lower cone (8) are respectively connected to the working cylinder via seat pins (9).

Images