Anchor release device for oil and gas wells

Abstract

An anchor release device for oil and gas wells. The main purpose is to solve the problem that the existing anchor release device and support anchor cannot be released after anchoring. The bottom of the upper joint (1) is connected to a piston, a hydraulic cylinder is provided on the outside of the piston, the bottom of the hydraulic cylinder is connected to a lower joint (13), the bottom of the piston is connected to a pull rod (14), and a longitudinal central channel (2) is provided inside the piston and the upper joint (1); the piston includes at least two piston monomers connected up and down, the hydraulic cylinder includes at least two hydraulic cylinder monomers connected up and down, the first piston (5) divides the inside of the first hydraulic cylinder (4) into a first air chamber (3) and a first hydraulic chamber (6), and the first piston (5) is provided with a first water hole (7) corresponding to the first hydraulic chamber (6). After the support is anchored, the anchor release device for oil and gas wells can cut off the shear pin by relying on the anchoring force generated by the hydraulic cylinder of the anchor release device, thereby realizing the release function of the anchor release device and the support.

Description

Technical Field

[0001] The invention relates to the field of downhole operation tools, in particular to an anchoring release device for oil and gas wells. Background Art

[0002] Before applying the downhole perforation penetration detection technology in the oil field, in order to ensure that the probe is aligned with the perforation hole, it is necessary to first anchor a fixed-position support device downhole. In the past, before the support device was anchored downhole, a steel ball was used to lock the center rod of the support anchor with the release rod at the lower end of the anchor release device. When anchoring, the center rod of the support anchor must move upward for a certain distance to release the locking function of the steel ball, so as to achieve release. However, when the downhole casing is severely deformed, the upward distance of the center rod becomes smaller, resulting in failure to release normally. Summary of the invention

[0003] In order to overcome the shortcomings of existing anchoring release devices and support anchors that cannot be released after anchoring, the present invention provides an anchoring release device for oil and gas wells. After the supporter is anchored, the anchoring release device for oil and gas wells can shear the shear pin by relying on the anchoring force generated by the hydraulic cylinder of the anchoring release device, thereby realizing the releasing function of the anchoring release device and the supporter.

[0004] The technical solution of the present invention is: an anchor release device for oil and gas wells, comprising an upper joint, the bottom of the upper joint is connected to a piston, a hydraulic cylinder is arranged outside the piston, the bottom of the hydraulic cylinder is connected to a lower joint, the bottom of the piston is connected to a pull rod, and a longitudinal central channel is arranged inside the piston and the upper joint;

[0005] The piston includes at least two piston monomers connected up and down, namely the first piston and the second piston. The hydraulic cylinder includes at least two hydraulic cylinder monomers connected up and down, namely the first hydraulic cylinder and the second hydraulic cylinder. The first piston divides the interior of the first hydraulic cylinder into a first air chamber and a first hydraulic chamber, and the second piston divides the interior of the second hydraulic cylinder into a second air chamber and a second hydraulic chamber. A first water hole is opened on the first piston corresponding to the first hydraulic chamber, and a second water hole is opened on the second piston corresponding to the second hydraulic chamber.

[0006] The first air chamber is located above the first hydraulic chamber, and the second air chamber is located above the second hydraulic chamber.

[0007] The bottom of the pull rod is connected to the release rod through a connecting sleeve, and the bottom of the lower joint is connected to the push cylinder.

[0008] The bottom of the push cylinder is connected to the key cylinder, the bottom of the key cylinder is provided with a support anchor shell, the lower end of the support anchor shell is connected to a cone, and an anchor claw is provided outside the cone; the bottom of the release rod is connected to the shear sleeve, the bottom of the shear sleeve is connected to the piston rod, and the bottom of the piston rod is connected to the center rod.

[0009] The release rod and the shear sleeve are connected via a shear pin.

[0010] The liquid in the central channel enters the first hydraulic chamber through the first water hole, and enters the second hydraulic chamber through the second water hole, so that the first piston and the second piston compress the first air chamber and the second air chamber respectively, driving the first piston, the second piston, the pull rod, and the release rod to move upward. At the same time, the first hydraulic cylinder, the second hydraulic cylinder, the lower joint, and the push tube move downward relative to the piston; the release rod pulls the anchor claw to move upward, and the push tube squeezes the support anchor shell to move downward, so that the cone expands the anchor claw and anchors it on the casing wall; after that, the release rod continues to move upward, breaking the shear pin to achieve release.

[0011] The present invention has the following beneficial effects: due to the adoption of the above scheme, the anchor release device can generate a shear force much greater than the shear pin, and the stroke of the piston in the hydraulic cylinder is greater than the anchoring stroke of the support anchor, so it can be ensured that after the supporter is anchored on the casing wall, the piston drives the piston rod to continue to move upward to break the shear pin, thereby achieving reliable release between the anchor release device and the supporter. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the structure of the present invention;

[0013] Figure 2 It is a schematic diagram of the connection between the lower end of the anchor release device and the support anchor.

[0014] In the figure, 1-upper joint, 2-center channel, 3-first air chamber, 4-first hydraulic cylinder, 5-first piston, 6-first hydraulic chamber, 7-first water hole, 8-second hydraulic cylinder, 9-second air chamber, 10-second piston, 11-second hydraulic chamber, 12-second water hole, 13-lower joint, 14-pull rod, 15-screw sleeve, 16-push cylinder, 17-connecting sleeve, 18-release rod, 19-top screw groove, 20-key cylinder, 21-shear pin, 22-shear sleeve, 23-piston rod, 24-support anchor shell, 25-cone, 26-anchor claw, 27-center rod, 28-anchor claw seat, 29-lower plug. DETAILED DESCRIPTION

[0015] The present invention will be further described below in conjunction with the accompanying drawings:

[0016] Depend on Figure 1 , Figure 2 As shown, an anchor release device for oil and gas wells includes an upper joint 1, the upper part of the upper joint 1 is connected to the upper tool through a thread, the inner side of the bottom of the upper joint 1 is connected to the piston, and sealing rings are provided between the upper joint 1 and the upper tool, and between the upper joint 1 and the piston. A longitudinal central channel 2 is provided inside the piston and the upper joint 1. A hydraulic cylinder is provided outside the piston, the bottom of the hydraulic cylinder is connected to the lower joint 13, and the bottom of the piston is connected to the pull rod 14.

[0017] The piston includes at least two piston monomers connected up and down, namely, a first piston 5 and a second piston 10, wherein the piston rod of the upper part of the first piston 5 is connected to the upper joint 1, and the lower part is connected to the piston rod of the second piston 10. The hydraulic cylinder includes at least two hydraulic cylinder monomers connected up and down, namely, a first hydraulic cylinder 4 and a second hydraulic cylinder 8, the two hydraulic cylinders are connected by threads, and a sealing ring is provided at the connection. A sealing ring is provided between the first piston 5 and the inner wall of the first hydraulic cylinder 4, and a sealing ring is provided between the second piston 10 and the inner wall of the second hydraulic cylinder 8. The first piston 5 divides the interior of the first hydraulic cylinder 4 into a first air chamber 3 and a first hydraulic chamber 6, wherein the first air chamber 3 is located above the first hydraulic chamber 6; the second piston 10 divides the interior of the second hydraulic cylinder 8 into a second air chamber 9 and a second hydraulic chamber 11, wherein the second air chamber 9 is located above the second hydraulic chamber 11. A first water hole 7 is opened on the first piston 5 corresponding to the first hydraulic chamber 6, and a second water hole 12 is opened on the second piston 10 corresponding to the second hydraulic chamber 11.

[0018] The number of the pistons and hydraulic cylinders can be increased as needed. The hydraulic cylinder at the lowest end is connected to the lower joint 13, and the piston at the lowest end is connected to the pull rod 14. The bottom of the pull rod 14 is connected to the release rod 18 through a connecting sleeve 17, the bottom of the release rod 18 is connected to the shear sleeve 22, the bottom of the shear sleeve 22 is connected to the piston rod 23, the bottom of the piston rod 23 is connected to the center rod 27, and the piston rod 23 and the shear sleeve 22 are provided with longitudinal flow channels inside. The lower end of the center rod 27 is connected to the lower plug 29. The bottom of the lower joint 13 is connected to the push tube 16, and the upper part of the push tube 16 is provided with a screw sleeve 15 for locking to prevent the push tube 16 from moving up and down. The bottom of the push tube 16 is connected to the key cylinder 20, and the bottom of the key cylinder 20 is provided with a support anchor shell 24, the lower end of the support anchor shell 24 is connected to the cone 25, and the cone 25 is provided with an anchor claw 26 outside. The upper part of the lower plug 29 is connected to the anchor claw seat 28, and the anchor claw seat 28 is located at the lower end of the anchor claw 26. The release rod 18 is connected to the shear sleeve 22 via a shear pin 21 .

[0019] Each hydraulic cylinder in the anchor release device is connected as a whole from top to bottom, and each piston is connected as a whole from top to bottom, and the inner and outer parts can move relative to each other. The liquid in the central channel 2 enters the first hydraulic chamber 6 through the first water hole 7, and enters the second hydraulic chamber 11 through the second water hole 12, so that the first piston 5 and the second piston 10 compress the air in the first air chamber 4 and the second air chamber 9 respectively, driving the first piston 5, the second piston 10, the pull rod 14, and the release rod 18 to move upward. At the same time, the first hydraulic cylinder 4, the second hydraulic cylinder 8, the lower joint 13, and the push tube 16 move downward relative to the piston. In this case, the release rod 18 pulls the anchor claw 26 to move upward, and the push tube 16 squeezes and supports the anchor shell 24 to move downward, so that the cone 25 expands the anchor claw 26 and anchors it into the casing wall. After that, the release rod 18 continues to move upward, thereby breaking the shear pin 22 to achieve the purpose of releasing the hand.

[0020] The anchoring release process is as follows: the tool string is transported to the target layer section in the well by cable transportation. The tool string is composed of a cable head, a magnetic locator, an electronic liquid inlet switch, an anchor release device, and a support anchor from top to bottom. After the ground control instrument is powered, the electronic liquid inlet switch at the upper end of the anchor release device is turned on, and the casing liquid in the well enters the central channel 2 along the liquid inlet hole of the electronic liquid inlet switch and the internal liquid inlet channel, and then enters the first hydraulic chamber 6 through the first water hole 7 and the second hydraulic chamber 11 through the second water hole 12. At this time, the liquid pressure at this depth acts on the lower end faces of the first piston 5 and the second piston 10. If the liquid in the well is water, a hydraulic cylinder at a vertical depth of 1 km can generate an anchoring force of 5.2 tons. As the liquid density increases and the vertical depth increases, the anchoring force can increase accordingly. At the same time, in order to obtain a greater anchoring force, the number of hydraulic cylinders can be increased. The lower end faces of the three pistons can generate a total of 15.6 tons of anchoring force. Under the action of the anchoring force, the first piston 5, the second piston 10, the pull rod 14, and the release rod 18 inside move upward relative to the first hydraulic cylinder 4, the second hydraulic cylinder 8, the lower joint 13, and the push tube 16 outside. At this time, the lower end surface of the step at the lower end of the push tube 16 is in close contact with the upper end surface of the key tube 20. As a result of the relative movement of the two parts, the release rod 18 pulls the shear sleeve 22, the piston rod 23, the center rod 27, the lower plug 29, the anchor claw seat 28, and the anchor claw 26 to move upward as a whole. Since the diameter of the cone 25 gradually increases from bottom to top, when the anchor claw 26 moves upward a certain distance, the cone 25 expands the anchor claw 26, thereby anchoring the supporter on the casing wall. At this time, because the stroke of the first piston 5 and the second piston 10 is greater than the anchoring stroke of the supporter, the release rod 18 continues to pull the shear sleeve 22 with the above-mentioned anchoring force. Since the anchoring force is much greater than the shear force of the shear pin 21, the shear pin 21 is pulled off, realizing the release function between the anchor release device and the support anchor.

Claims

1. An anchor release device for oil and gas wells, comprising an upper joint (1), characterized in that: The bottom of the upper joint (1) is connected to a piston, a hydraulic cylinder is provided outside the piston, the bottom of the hydraulic cylinder is connected to the lower joint (13), the bottom of the piston is connected to a pull rod (14), and a longitudinal center channel (2) is provided inside the piston and the upper joint (1); the bottom of the pull rod (14) is connected to a release rod (18) via a connecting sleeve (17), the bottom of the lower joint (13) is connected to a push cylinder (16), the bottom of the push cylinder (16) is connected to a key cylinder (20), the bottom of the key cylinder (20) is provided with a support anchor shell (24), the lower end of the support anchor shell (24) is connected to a cone (25), and an anchor claw (26) is provided outside the cone (25); the bottom of the release rod (18) is connected to a shear sleeve (22) via a shear pin (21), the bottom of the shear sleeve (22) is connected to a piston rod (23), and the bottom of the piston rod (23) is connected to a center rod (27); The piston comprises at least two piston monomers connected up and down, namely a first piston (5) and a second piston (10); the hydraulic cylinder comprises at least two hydraulic cylinder monomers connected up and down, namely a first hydraulic cylinder (4) and a second hydraulic cylinder (8); the first piston (5) divides the interior of the first hydraulic cylinder (4) into a first air chamber (3) and a first hydraulic chamber (6); the second piston (10) divides the interior of the second hydraulic cylinder (8) into a second air chamber (9) and a second hydraulic chamber (11); a first water hole (7) is opened on the first piston (5) at a position corresponding to the first hydraulic chamber (6); a second water hole (12) is opened on the second piston (10) at a position corresponding to the second hydraulic chamber (11); the first air chamber (3) is located above the first hydraulic chamber (6); and the second air chamber (9) is located above the second hydraulic chamber (11).

2. The anchor release device for oil and gas wells according to claim 1, characterized in that: The liquid in the central channel (2) enters the first hydraulic chamber (6) through the first water hole (7) and enters the second hydraulic chamber (11) through the second water hole (12), so that the first piston (5) and the second piston (10) compress the first air chamber (4) and the second air chamber (9) respectively, driving the first piston (5), the second piston (10), the pull rod (14) and the release rod (18) to move upwards. At the same time, the first hydraulic cylinder (4), the second hydraulic cylinder (8), the lower joint (13) and the push tube (16) move downwards relative to the pistons. The release rod (18) pulls the anchor claw (26) to move upwards, and the push tube (16) squeezes the supporting anchor shell (24) to move downwards, so that the cone (25) expands the anchor claw (26) and anchors it on the casing wall. Afterwards, the release rod (18) continues to move upwards, breaking the shear pin (22) to achieve release.

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