Underwater remote pre-tightening shearing tool and shearing method

Abstract

The present invention relates to an underwater remote pre-tightening shearing tool and shearing method, comprising a cylinder body, a piston rod disposed within the cylinder body, a blade holder disposed at one end of the cylinder body, and a pressure-resistant rear cover mounted at the other end. An electric explosion device for propelling the piston rod is disposed within the area enclosed by the pressure-resistant rear cover. The piston rod extends beyond the cylinder body end face at the end facing the blade holder and is mounted with a blade. A compression spring is mounted at the end of the piston rod proximate the pressure-resistant rear cover. A groove is formed on the outer circumferential surface of the piston rod where it contacts the inner wall of the cylinder body, and a spring pin penetrates the cylinder body and falls into the groove. A pre-tightening distance is reserved for the piston rod in its initial state. The present invention remotely triggers the shearing action via an underwater acoustic receiver, is unaffected by sea conditions, and is triggered by the electric explosion device, allowing it to remain underwater on standby for extended periods of time.

Description

Technical Field

[0001] The present invention relates to the technical field of underwater operations, in particular to an underwater remote pre-tightening shearing tool and a shearing method. Background Art

[0002] Underwater operations often involve several situations: At the start of underwater operations, equipment must be secured with steel cables to prevent underwater currents from affecting operations; and after the underwater operation is completed, the equipment must be recovered, requiring the steel cables to be broken. These situations require the ROV to perform two underwater operations. In adverse sea conditions, ROV operations have a low success rate and are time-consuming. This is especially true when adverse sea conditions pose a safety threat to surface platforms, forcing the underwater equipment to be abandoned, resulting in significant financial losses. Summary of the Invention

[0003] In response to the shortcomings of the above-mentioned existing production technology, the applicant provides a rationally structured underwater remote pre-tightening shearing tool and shearing method, which adopts remote control to achieve remote shearing destruction, is not affected by sea conditions, and is convenient to work; the cutting work is triggered by an electric explosion device, has reliable sealing, can be placed underwater for a long time, and has no leakage.

[0004] The technical solutions adopted in the present invention are as follows:

[0005] An underwater remote pre-tightening shearing tool comprises a cylinder body, a piston rod is arranged in the cylinder body, a knife seat is arranged at one end of the cylinder body, and a pressure-resistant rear cover is installed at the other end. An electric explosion device for pushing the piston rod to extend is arranged in the area surrounded by the pressure-resistant rear cover.

[0006] One end of the piston rod facing the blade seat extends out of the end surface of the cylinder body and is equipped with a blade;

[0007] A compression spring is installed on the end of the piston rod close to the pressure-resistant rear cover; a groove is provided on the outer circumferential surface of the piston rod that contacts the inner wall of the cylinder, and a spring pin is passed through the cylinder body and falls into the groove;

[0008] The initial state of the piston rod reserves a retracted preload distance.

[0009] A recessed groove is provided on the outer circumferential surface of the piston rod. Of the two side walls of the recessed groove, the side wall close to the knife seat is an inclined surface, and the inclined direction is obliquely directed from the groove bottom to the side of the knife seat.

[0010] The initial state of the spring pin is that it falls on the bottom of the sink groove, and the initial state of the compression spring is that it has a compression amount.

[0011] An intermediate flange is provided between the cylinder body and the pressure-resistant rear cover, and the end of the spring facing away from the piston rod presses against the intermediate flange; the axial length between the spring pin and the intermediate flange is greater than the length between the piston rod and the intermediate flange in the initial state.

[0012] One end of the compression spring close to the piston rod is embedded in the end surface of the piston rod.

[0013] The knife seat is an open structure, and a channel for accommodating the movement of the blade is opened on the knife seat, and the channel is communicated with the open structure.

[0014] The axial length of the channel on the blade seat is greater than the axial length of the blade.

[0015] The open side wall of the knife seat is an inclined surface, and the angle between the inclined surface and the movement path of the blade is an acute angle.

[0016] An air filling valve and a water sound receiver are installed on the middle flange. The air filling valve is connected to the compartment of the pressure-resistant rear cover, and the water sound receiver is connected to the electric explosion device.

[0017] A shearing method for an underwater remote pre-tightening shearing tool comprises the following steps:

[0018] Before operation, the pressure-resistant rear cover is inflated through the inflation valve, and the piston rod is locked under the action of the compression spring and the spring pin. At this time, the blade is retracted into the channel of the blade holder;

[0019] The shearing tool is brought underwater, and the external manipulator drives the shearing tool to hook the steel cable. Then the manipulator pushes the shearing tool, causing relative movement between the steel cable and the knife holder. The steel cable pushes the blade, which pushes the piston rod back, forming a pre-tightened state of compression of the compression spring.

[0020] The spring pin retracts at this time and no longer plays a limiting role; the piston rod extends under the action of the return force of the compression spring, and the blade pushes the steel cable until it is clamped on the blade seat;

[0021] When it is necessary to cut the steel cable, the hydroacoustic receiver controls the electric explosion device to explode, and the high-pressure air in the pressure-resistant back cover further pushes the piston rod, and the piston rod drives the blade to cut the steel cable.

[0022] The beneficial effects of the present invention are as follows:

[0023] The invention has a compact and reasonable structure and is easy to operate. The shearing action is remotely triggered by an underwater acoustic receiver and is not affected by sea conditions. The shearing operation has high reliability.

[0024] The present invention does not require an external power source, has a simple structure and is low in cost;

[0025] The present invention adopts an electric explosion device to trigger, can be placed underwater for a long time, is not easy to leak, and is suitable for working conditions with long construction periods;

[0026] In the present invention, the blade holder simultaneously functions as an anvil and a hook, making cable hooking and alignment operations simple and convenient, making it suitable for underwater operations. The shearing tool of the present invention has two operating states: a clamping state and a cutting state. In the clamping state, since the initial spring pin limiting force is removed, the compression spring pushes the blade out, pushing the steel cable already resting on the blade against the blade holder. Due to the limited thrust of the compression spring, the clamping state is maintained, but not cutting.

[0027] The side wall of the groove corresponding to the spring pin is an inclined surface, which makes it easy for the spring pin to slide out of the groove when the steel cable pushes the piston rod to retract. The spring pin after sliding out will not extend again without external force, thereby achieving the purpose of releasing the limiting force, and the releasing action is convenient and quick.

[0028] The present invention adopts an electric explosion device to explode the connection position between the middle flange and the cylinder body, so that the cylinder body receives high-pressure gas at the pressure-resistant rear cover, pushes out the piston rod again, and causes the blade to cut the steel cable.

[0029] Therefore, the present invention adopts a compression spring with lower pressure and high-pressure air with higher pressure to push the piston rod twice, thereby realizing the two actions of clamping and cutting, and the two actions will not be confused, and the operation is convenient and accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a cross-sectional view of the overall structure of the present invention.

[0031] Figure 2 for Figure 1 The enlarged view of part A is used to show the position of the sink.

[0032] Figure 3 Schematic diagram of the shearing tool hanging cable of the present invention.

[0033] Figure 4 This is a schematic diagram of the shearing tool of the present invention being hung with a cable and the steel cable pushing the piston rod backward.

[0034] Figure 5 This is a schematic diagram of the piston rod extending out of the shearing device of the present invention to clamp the steel cable.

[0035] Including: 1. Pressure-resistant rear cover; 2. Cylinder body; 3. Piston rod; 4. Blade holder; 5. Electric explosion device; 6. Blade; 7. Compression spring; 8. Spring pin; 9. Intermediate flange; 10. Inflatable valve; 11. Water acoustic receiver;

[0036] 301, sink;

[0037] 401, channel. DETAILED DESCRIPTION

[0038] The specific embodiments of the present invention will be described below with reference to the accompanying drawings.

[0039] like Figure 1-Figure 5 As shown, the underwater remote pre-tightening shearing tool of this embodiment includes a cylinder body 2, a piston rod 3 is provided in the cylinder body 2, a knife seat 4 is provided at one end of the cylinder body 2, and a pressure-resistant rear cover 1 is installed at the other end. An electric explosion device 5 for pushing the piston rod 3 out is provided in the area surrounded by the pressure-resistant rear cover 1.

[0040] One end of the piston rod 3 facing the blade seat 4 extends out of the end surface of the cylinder body 2 and is equipped with a blade 6;

[0041] A compression spring 7 is installed at one end of the piston rod 3 close to the pressure-resistant rear cover 1; a groove is provided on the outer circumferential surface of the piston rod 3 that contacts the inner wall of the cylinder body 2, and a spring pin 8 is passed through the cylinder body 2 and falls into the groove;

[0042] The initial state of the piston rod 3 reserves a pre-tightening distance for retraction.

[0043] A recessed groove 301 is formed on the outer surface of the piston rod 3 . The sidewalls of the recessed groove 301 , which are close to the knife seat 4 , are inclined surfaces, with the inclined direction pointing from the bottom of the groove to the side of the knife seat 4 .

[0044] The spring pin 8 initially falls on the bottom of the recessed groove 301 , and the compression spring 7 initially has a compressed amount.

[0045] An intermediate flange 9 is set between the cylinder body 2 and the pressure-resistant rear cover 1, and the end of the spring facing away from the piston rod 3 is pressed against the intermediate flange 9; the axial length between the spring pin 8 and the intermediate flange 9 is greater than the length between the piston rod 3 and the intermediate flange 9 in the initial state.

[0046] One end of the compression spring 7 close to the piston rod 3 is embedded in the end surface of the piston rod 3 .

[0047] The knife seat 4 is an open structure. A channel 401 for accommodating the movement of the blade 6 is provided on the knife seat 4. The channel 401 is communicated with the open structure.

[0048] The axial length of the channel 401 on the blade seat 4 is greater than the axial length of the blade 6 .

[0049] The open side wall of the blade seat 4 is an inclined surface, and the angle between the inclined surface and the movement path of the blade 6 is an acute angle.

[0050] An air filling valve 10 and a water sound receiver 11 are installed on the middle flange 9 . The air filling valve 10 is connected to the chamber of the pressure-resistant rear cover 1 , and the water sound receiver 11 is connected to the electric explosion device 5 .

[0051] The shearing method of the underwater remote pre-tightening shearing tool of this embodiment includes the following steps:

[0052] Before operation, the chamber of the pressure-resistant rear cover 1 is inflated through the inflation valve 10, and the piston rod 3 is locked under the action of the compression spring 7 and the spring pin 8. At this time, the blade 6 is retracted into the channel 401 of the blade holder 4;

[0053] The shearing tool is brought underwater, and the external manipulator drives the shearing tool to hook the steel cable. Then the manipulator pushes the shearing tool, causing relative movement between the steel cable and the knife holder 4. The steel cable pushes the blade 6, which pushes the piston rod 3 back, forming a pre-tightened state of compression of the compression spring 7.

[0054] The spring pin 8 retracts at this time and no longer plays a limiting role; the piston rod 3 extends under the action of the restoring force of the compression spring 7, and the blade 6 pushes the steel cable until it is clamped on the blade seat 4;

[0055] When the steel cable needs to be cut, the hydroacoustic receiver 11 controls the electric explosion device 5 to explode, and the high-pressure air in the pressure-resistant rear cover 1 further pushes the piston rod 3, and the piston rod 3 drives the blade 6 to cut the steel cable.

[0056] The specific structure and working process of the present invention are as follows:

[0057] like Figure 1 As shown, the cylinder body 2 of the present invention is sealed with a pressure-resistant rear cover 1 and a blade holder 4 at both ends. The pressure-resistant rear cover 1 is equipped with an electric explosion device 5. The chamber formed by the pressure-resistant rear cover 1 and the intermediate flange 9 is also pre-filled with high-pressure gas. When the electric explosion device 5 explodes, the high-pressure gas flows into the relatively low-pressure rodless chamber, pushing the piston rod 3 to extend.

[0058] A spring pin 8 is provided near the middle flange 9 of the cylinder body 2. Figure 2 As shown, the initial state of the spring pin 8 is embedded in the recessed groove on the piston rod 3, limiting the piston rod 3. At this time, the relative position between the piston rod 3 and the cylinder body 2 remains unchanged, the blade 6 is retracted in the channel 401, and the compression spring 7 has a certain amount of compression.

[0059] like Figure 3 As shown, the shearing tool is hung with a steel cable, and the inclined opening of the knife seat 4 is convenient for the steel cable to enter; Figure 3 After the middle position is placed, the external manipulator pushes the shearing device to embed the steel cable into the channel 401 of the knife seat 4. The steel cable enters the channel 401 and pushes the piston rod 3, and the piston rod 3 retracts. Figure 4 As shown, at this time, the compression spring 7 is compressed, and the spring pin 8 comes out along the side wall of the groove. At this time, the piston rod 3 is no longer subject to the limiting force, but is subject to the axial thrust of the compression spring 7.

[0060] like Figure 5As shown, when the external manipulator removes the external force, the compression spring 7 is reset. The initial state is a compressed state. After being further compressed by the steel cable, the reset force of the compression spring 7 increases, pushing the piston rod 3 to extend. Since the blade 6 is in contact with the steel cable at this time, the steel cable is pushed by the blade 6 to be tightened in the knife seat 4.

[0061] When the operation is completed and the steel cable needs to be cut, a signal is sent to the hydroacoustic receiver 11 to control the electric explosion device 5 to explode, and the high-pressure air pushes the piston rod 3 to extend again to cut the steel cable.

[0062] In this embodiment, a sealing ring is provided between the intermediate flange 9 and the pressure-resistant rear cover 1 and the cylinder body 2; a sealing ring and a support ring are provided between the piston rod 3 and the inner wall of the cylinder body 2; and a sealing ring is provided between the knife seat 4 and the pressure-resistant rear cover 1. The electric explosion device 5 is prior art and will not be described in detail in this invention.

[0063] The present invention has two working states: clamping the steel cable and cutting the steel cable. The action of triggering the clamping of the steel cable is realized simultaneously when the cable is hung, and the operation is more convenient and quick; the cutting of the steel cable can be triggered after a long operation is completed. During the waiting process, the entire shearing tool can remain in an underwater position ready to be triggered, and the working state is stable and reliable.

[0064] The above description is an explanation of the present invention, not a limitation of the present invention. The scope of the present invention is defined in the claims. Any modifications may be made within the scope of protection of the present invention.

Claims

1. An underwater remote pre-tightening shearing tool, comprising a cylinder (2) in which a piston rod (3) is provided, characterized in that: The cylinder body (2) is provided with a knife seat (4) at one end and a pressure-resistant rear cover (1) at the other end. An electric explosion device (5) for pushing the piston rod (3) out is provided in the area surrounded by the pressure-resistant rear cover (1). One end of the piston rod (3) facing the blade seat (4) extends out of the end surface of the cylinder body (2) and is equipped with a blade (6); A compression spring (7) is installed at one end of the piston rod (3) close to the pressure-resistant rear cover (1); a groove is provided on the outer circumferential surface of the piston rod (3) in contact with the inner wall of the cylinder body (2); a spring pin (8) is passed through the cylinder body (2) and falls into the groove; The piston rod (3) has a pre-tightening distance reserved for retraction in its initial state; A recessed groove (301) is provided on the outer circumferential surface of the piston rod (3); and the side wall of the recessed groove (301) close to the knife seat (4) is an inclined surface, with the inclined direction being obliquely directed from the bottom of the groove toward the side of the knife seat (4); The initial state of the spring pin (8) is that it falls on the bottom of the sink groove (301), and the initial state of the compression spring (7) is that it has a compression amount; The side wall of the sink groove (301) corresponding to the spring pin (8) is an inclined surface, so that the spring pin (8) can slide out of the sink groove (301) when the steel cable pushes the piston rod to retract. The spring pin (8) after sliding out will not extend again without external force.

2. The underwater remote pre-tightening shearing tool according to claim 1, characterized in that: An intermediate flange (9) is provided between the cylinder body (2) and the pressure-resistant rear cover (1), and one end of the spring facing away from the piston rod (3) is pressed against the intermediate flange (9); the axial length between the spring pin (8) and the intermediate flange (9) is greater than the length between the piston rod (3) and the intermediate flange (9) in the initial state.

3. The underwater remote pre-tightening shearing tool according to claim 1, characterized in that: One end of the compression spring (7) close to the piston rod (3) is embedded in the end surface of the piston rod (3).

4. The underwater remote pre-tightening shearing tool according to claim 1, characterized in that: The knife seat (4) is an open structure. A channel (401) for accommodating the movement of the blade (6) is provided on the knife seat (4), and the channel (401) is communicated with the open structure.

5. The underwater remote pre-tightening shearing tool according to claim 4, characterized in that: The axial length of the channel (401) on the blade seat (4) is greater than the axial length of the blade (6).

6. The underwater remote pre-tightening shearing tool according to claim 4, characterized in that: The open side wall of the knife seat (4) is an inclined surface, and the angle between the inclined surface and the movement path of the blade (6) is an acute angle.

7. The underwater remote pre-tightening shearing tool according to claim 2, characterized in that: An air filling valve (10) and an underwater sound receiver (11) are installed on the intermediate flange (9); the air filling valve (10) is connected to the chamber of the pressure-resistant rear cover (1); and the underwater sound receiver (11) is connected to the electric explosion device (5).

8. A shearing method for an underwater remote pre-tightening shearing tool according to claim 1, characterized in that: The steps include: Before operation, the chamber of the pressure-resistant rear cover (1) is inflated through the inflation valve (10), and the piston rod (3) is locked under the action of the compression spring (7) and the spring pin (8), at which time the blade (6) is retracted into the channel (401) of the blade holder (4); The shearing tool is brought underwater, and an external manipulator drives the shearing tool to hook the steel cable, and then the manipulator pushes the shearing tool, so that the steel cable and the knife seat (4) move relative to each other, and the steel cable pushes the blade (6) and thus pushes the piston rod (3) back, forming a pre-tightened state of compression of the compression spring (7); The spring pin (8) retracts at this time and no longer plays a limiting role; the piston rod (3) extends under the action of the restoring force of the compression spring (7), and the blade (6) pushes the steel cable until it is clamped on the blade seat (4); When the steel cable needs to be cut, the hydroacoustic receiver (11) controls the electric explosion device (5) to explode, and the high-pressure air in the pressure-resistant rear cover (1) further pushes the piston rod (3), and the piston rod (3) drives the blade (6) to cut the steel cable.

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