Pressure compensation and valve closing driving device of pressure maintaining wire line coring drilling tool

Abstract

The invention relates to the field of wire-line coring drilling tools, and discloses a pressure compensation and valve closing driving device of a pressure-maintaining wire-line coring drilling tool, which comprises an outer cylinder and an inner cylinder assembled in the outer cylinder, a high-pressure gas storage cylinder is arranged at the top of the inner cylinder, a gas release mechanism is positioned at the bottom of the high-pressure gas storage cylinder, and an isolation piston is positioned below the gas release mechanism. A throttling cavity is formed in the bottom of the isolation piston, a valve closing driving mechanism is arranged below the throttling cavity, the pressure maintaining cavity is communicated with the throttling cavity through a throttling and pressure compensation connector, and a one-way valve is arranged on the throttling and pressure compensation connector. The isolation piston is pushed by high-pressure gas to drive liquid in the throttling cavity to do work so as to drive the valve closing driving mechanism to close a sealing valve at the bottom of the pressure maintaining cavity, and pressure compensation is provided for the pressure maintaining cavity through the throttling and pressure compensation connector. The gas release mechanism releases high-pressure gas to push the isolation piston to do work, driving power is provided for closing of the sealing valve of the pressure maintaining cavity, meanwhile, pressure compensation is provided for the pressure maintaining cavity, and a hydrate sample in the pressure maintaining cavity is effectively prevented from being decomposed.

Description

Technical Field

[0001] The present application relates to the field of rope coring drill tools, and in particular to a pressure compensation and valve closing drive device for a pressure-maintaining rope coring drill tool. Background Art

[0002] Natural gas hydrates are an energy resource with great potential. In order to accurately evaluate them and understand their storage conditions, a large number of hydrate samples in their original state need to be obtained. One of the characteristics of natural gas hydrates is that they are very sensitive to changes in temperature and pressure and are very easy to decompose. Therefore, in order to obtain the required hydrate samples, the corresponding sampler needs to have perfect heat preservation and pressure maintenance functions.

[0003] The overall pressure-maintaining technology of the hydrate sampler is that the drill bit adopts an inner and outer cylinder structure. After obtaining the sample, the sample is dragged and dropped into the pressure-maintaining chamber through the differential method of the inner and outer cylinders. The sealing units at the upper and lower ends of the pressure-maintaining chamber are effective to achieve pressure maintenance of the sample. The upper end of the pressure-maintaining chamber is generally sealed on the side, and the lower end is generally sealed with a plate valve or a ball valve due to the need to set up a sample channel. Under normal circumstances, if the seal of the sampler pressure-maintaining chamber is not closed in time at the sampling site, as the water depth of the salvaged drill bit decreases, the pressure in the pressure-maintaining cylinder will decrease and cause the sample to decompose. Therefore, a controllable active method is used to close the pressure-maintaining chamber seal in time, which can better achieve pressure maintenance of the sampler at the initial sampling position. At the same time, as the water depth decreases, the environmental pressure of the sampler decreases, the sampler pressure-maintaining chamber will expand slightly, and it will also cause the hydrate sample to decompose.

[0004] Therefore, how to effectively prevent the decomposition of the hydrate sample in the pressure-maintaining chamber is a problem that needs to be solved by those skilled in the art. Summary of the invention

[0005] The purpose of the present application is to provide a pressure compensation and valve closing drive device for a pressure-maintaining rope coring drill, which is used to solve the problem that as the water depth decreases, the sampler environmental pressure decreases, the sampler pressure-maintaining chamber will slightly expand, causing the hydrate sample to decompose.

[0006] In order to solve the above technical problems, the present application provides a pressure compensation and valve closing drive device for a pressure-maintaining rope coring drill, comprising: an outer cylinder and an inner cylinder assembled in the outer cylinder, the top of the inner cylinder is a high-pressure gas storage cylinder, a gas release mechanism is located at the bottom of the high-pressure gas storage cylinder, the gas release mechanism is used to seal and release the high-pressure gas in the high-pressure gas storage cylinder, the isolation piston is located below the gas release mechanism, the bottom of the isolation piston is a throttling cavity, a valve driving mechanism is arranged below the throttling cavity, the pressure-maintaining cavity is connected to the throttling cavity through a throttling and pressure compensation joint, a one-way valve is arranged on the throttling and pressure compensation joint, the isolation piston moves toward the throttling cavity under the push of the high-pressure gas, drives the liquid in the throttling cavity to do work to drive the valve closing drive mechanism to close the sealing valve at the bottom of the pressure-maintaining cavity, and provides pressure compensation to the pressure-maintaining cavity through the throttling and pressure compensation joint.

[0007] Optionally, the high-pressure air cylinder includes an inflation connector, an air cylinder, an inflation valve plug and a release valve core. The top of the air cylinder is connected to the inflation connector, the release valve core is plugged into a through hole at the bottom of the air cylinder, the inflation valve plug is arranged in the inflation connector, and the through hole is provided with a hole seal.

[0008] Optionally, the outer cylinder is composed of a limit sleeve, a top sealing shell and a pressure maintaining chamber shell which are connected in sequence, and the top sealing shell is detachably connected to the limit sleeve and the pressure maintaining chamber shell respectively, and the inner cylinder is composed of the inflation joint, the gas storage cylinder, the release valve shell and the top sealing joint, and when the inner cylinder moves axially along the outer cylinder, the gas release mechanism is triggered to release the high-pressure gas in the gas storage cylinder.

[0009] Optionally, the release valve core includes a plunger and a locking block, the plunger is coaxially assembled on the top of the locking block, the plunger is used to seal the through hole at the bottom of the gas cylinder, the diameter of the locking block is larger than the diameter of the plunger, a gas release channel is provided inside the locking block, and a first locking groove and a first annular sealing groove are provided on the outer surface of the locking block, the first annular sealing groove is equipped with a first annular seal, the first annular seal is abutted against the release valve housing, and when the plunger is disengaged from the through hole at the bottom of the gas cylinder, the high-pressure gas is released through the gas release channel.

[0010] Optionally, the gas release mechanism includes a trigger sleeve, a release valve housing, a release valve lock block, a reset spring and a limit sleeve, the upper part of the release valve housing is threadedly connected to the lower part of the gas cylinder, the outer circumferential surface of the release valve housing is sequentially sleeved with the trigger sleeve and the reset spring, the top of the trigger sleeve abuts against the gas cylinder or the limit sleeve, the bottom of the trigger sleeve abuts against the top of the reset spring, a support boss is provided in the middle of the outer circumferential surface of the release valve housing, the bottom of the reset spring abuts against the support boss, a lock block through hole is provided on the side wall of the release valve housing, a release valve lock block is installed in the lock block through hole, and a release groove is provided on the side of the trigger sleeve close to the release valve housing, when the release valve lock block is located in the first locking groove, the gas release mechanism is used to limit the release valve core so that the plunger is plugged into the through hole at the bottom of the gas cylinder, and when the release valve lock block is located in the release groove, the release valve core moves downward under the action of the high-pressure gas to release the high-pressure gas through the gas release channel.

[0011] Optionally, the isolation piston includes an isolation piston sleeve, an inner hole piston rod and a locking nut, the isolation piston sleeve is sleeved on the outer circumferential surface of the inner hole piston rod, the top of the inner hole piston rod is provided with a limiting boss, the tail of the inner hole piston rod is provided with an external thread, the external thread cooperates with the internal thread of the locking nut to limit the isolation piston sleeve between the limiting boss and the locking nut, the outer circumferential surface of the inner hole piston rod is provided with a reset sealing surface and a limiting notch in sequence from the limiting boss to the external thread, the isolation piston sleeve is provided with a second annular sealing groove near the inner circumferential surface of the inner hole piston rod, the second annular sealing groove is equipped with a second annular seal, and the second annular seal The inner diameter of the component matches the outer diameter of the reset sealing surface provided on the inner hole piston rod, the inner diameter of the second annular seal is larger than the outer diameter of the inner hole piston rod provided with the limiting groove, when the locking nut is unlocked, the isolation piston sleeve moves toward the tail of the inner hole piston rod so that the second annular seal is located at the limiting groove, when the locking nut is locked, the isolation piston sleeve moves toward the head of the inner hole piston rod so that the second annular seal abuts against the reset sealing surface, the outer circumferential surface of the isolation piston sleeve is provided with a third annular sealing groove, the third annular seal is assembled in the third annular sealing groove, and the third annular seal abuts against the release valve housing.

[0012] Optionally, the isolation piston sleeve is also provided with a mounting hole, in which a limiting screw is assembled, and a first limiting step and a second limiting step are sequentially provided along the length direction of the limiting slot to limit the limiting screw between the first limiting step and the second limiting step, and when the limiting screw abuts against the second limiting step, the second annular seal is located at the limiting slot, and when the limiting screw abuts against the first limiting step, the second annular seal is located at the reset sealing surface.

[0013] Optionally, the throttling chamber is composed of a top seal, a top sealing joint and a throttling and pressure compensation joint, the upper part of the top sealing joint is threadedly connected to the lower part of the release valve housing, the lower part of the top sealing joint is connected to the throttling and pressure compensation joint, both ends of the top sealing joint are provided with mounting grooves for assembling the top seal, the middle part of the top sealing joint is the outlet channel of the liquid in the throttling chamber, and the top seal is used to move axially along the outer cylinder in the inner cylinder to seal the top of the pressure maintaining chamber.

[0014] Optionally, the valve closing drive mechanism includes a spring claw lock sleeve, a pressure-maintaining chamber shell, a top sealing shell, a spring claw and a pre-stressed spring. The outer side of the spring claw lock sleeve is a sealing boss, an unlocking cylinder and a locking cylinder from top to bottom, and the inner side of the spring claw lock sleeve is a top sealing surface, which cooperates with the top sealing member. The upper part of the pressure-maintaining chamber shell is threadedly connected to the top sealing shell, and a sealing cylinder and a second locking groove are sequentially arranged from the upper thread of the pressure-maintaining chamber shell downward. A sealing ring is arranged on the outer peripheral surface of the top sealing joint, and the sealing ring is located at the Below the outlet channel, the sealing ring abuts against the sealing cylinder of the pressure-maintaining chamber housing and is located above the sealing boss. The top of the spring claw is an elastically deformable contact, and the contact is located between the second locking groove and the unlocking cylinder. The tail of the spring claw extends between the pressure-maintaining chamber housing and the locking cylinder of the spring claw lock sleeve, and is connected to the valve closing cylinder. The valve closing cylinder is connected to the sealing valve of the pressure-maintaining chamber, and the unlocking cylinder is sleeved with the pre-compression spring, and both ends of the pre-compression spring abut against the sealing boss and the contacts of the spring claw respectively.

[0015] Optionally, the side of the release valve locking block facing the trigger sleeve is a release contact surface, the side of the release valve locking block facing the release valve core is a locking contact surface, the release contact surface is a convex surface, and the locking contact surface is a concave surface.

[0016] The present application provides a pressure compensation and valve closing drive device for a pressure-maintaining rope coring drill, comprising: an outer tube and an inner tube assembled in the outer tube, the top of the inner tube is a high-pressure gas storage cylinder, a gas release mechanism is located at the bottom of the high-pressure gas storage cylinder, the gas release mechanism is used to block and release the high-pressure gas in the high-pressure gas storage cylinder, an isolation piston is located below the gas release mechanism, the bottom of the isolation piston is a throttling cavity, a valve driving mechanism is arranged below the throttling cavity, the pressure-maintaining cavity is connected to the throttling cavity through a throttling and pressure compensation joint, a one-way valve is arranged on the throttling and pressure compensation joint, the isolation piston moves toward the throttling cavity under the push of high-pressure gas, drives the liquid in the throttling cavity to do work to drive the valve closing drive mechanism to close the sealing valve at the bottom of the pressure-maintaining cavity, and provides pressure compensation to the pressure-maintaining cavity through the throttling and pressure compensation joint. After the pressure-maintaining cavity collects the hydrate sample, the gas release mechanism releases the high-pressure gas to push the isolation piston to do work, provides driving power for closing the sealing valve of the pressure-maintaining cavity, and provides pressure compensation for the pressure-maintaining cavity, which can effectively prevent the decomposition of the hydrate sample in the pressure-maintaining cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 A cross-sectional view of a pressure compensation and valve closing drive device for a pressure-maintaining rope coring drill tool is provided for an embodiment of the present application;

[0019] Figure 2 A cross-sectional view of another pressure compensation and valve closing drive device for a pressure-maintaining rope coring drill tool is provided for an embodiment of the present application;

[0020] Figure 3 A cross-sectional view of a release valve core provided in an embodiment of the present application;

[0021] Figure 4 A cross-sectional view of a release valve lock block provided in an embodiment of the present application;

[0022] Figure 5 A cross-sectional view of an isolation piston provided in an embodiment of the present application;

[0023] Figure 6 A cross-sectional view of a spring claw lock sleeve provided in an embodiment of the present application;

[0024] The accompanying drawings are marked as follows: 1 is a limit sleeve, 2 is an inflation joint, 3 is an inflation valve plug, 4 is a top sealing shell, 5 is an air storage cylinder, 6 is a trigger sleeve, 7 is a release valve shell, 8 is a release valve lock block, 9 is a release valve core, 10 is a return spring, 11 is an isolation piston, 12 is a claw lock sleeve, 13 is a pressure-maintaining chamber shell, 14 is a claw, 15 is a top seal, 16 is a throttling chamber, 17 is a top sealing joint, 18 is a valve-off cylinder, 19 is a one-way valve, 20 is a throttling and pressure compensation joint, 21 is a pressure-maintaining chamber , 801 is the release contact surface, 802 is the locking contact surface, 901 is the plunger, 902 is the gas release channel, 903 is the first locking groove, 904 is the first annular seal, 1101 is the inner hole piston rod, 1102 is the second annular seal, 1103 is the third annular seal, 1104 is the limit screw, 1105 is the isolation piston sleeve, 1106 is the locking nut, 1201 is the sealing boss, 1202 is the unlocking cylinder, 1203 is the locking cylinder, and 1204 is the top sealing surface. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0026] The core of the present application is to provide a pressure compensation and valve closing drive device for a pressure-maintaining rope coring drill, which is used to effectively prevent the decomposition of hydrate samples in the pressure-maintaining chamber.

[0027] In order to enable persons skilled in the art to better understand the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the terms "upper", "lower", "left", "right", "top", "bottom" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0028] Figure 1 A cross-sectional view of a pressure compensation and valve closing drive device for a pressure-maintaining rope coring drill according to an embodiment of the present application is provided. Figure 2 A cross-sectional view of another pressure compensation and valve closing drive device for a pressure-maintaining rope coring drill is provided for an embodiment of the present application, such as Figure 1 and Figure 2As shown, a pressure compensation and valve closing drive device for a pressure-maintaining rope coring drill comprises: an outer cylinder and an inner cylinder assembled in the outer cylinder, the top of the inner cylinder is a high-pressure gas storage cylinder, a gas release mechanism is located at the bottom of the high-pressure gas storage cylinder, the gas release mechanism is used to block and release the high-pressure gas in the high-pressure gas storage cylinder, an isolation piston 11 is located below the gas release mechanism, the bottom of the isolation piston 11 is a throttling cavity 16, a valve driving mechanism is arranged below the throttling cavity 16, a pressure-maintaining cavity 21 is connected with the throttling cavity 16 through a throttling and pressure compensation joint 20, a one-way valve 19 is arranged on the throttling and pressure compensation joint 20, the isolation piston 11 moves toward the throttling cavity 16 under the push of the high-pressure gas, drives the liquid in the throttling cavity 16 to do work to drive the valve closing drive mechanism to close the sealing valve at the bottom of the pressure-maintaining cavity 21, and provides pressure compensation for the pressure-maintaining cavity 21 through the throttling and pressure compensation joint 20.

[0029] The embodiment of the present application does not specifically limit the outer tube and the inner tube. The inner tube can be coaxially assembled in the outer tube. Specifically, the outer tube is composed of a limiting sleeve 1, a top sealing shell 4 and a pressure-maintaining chamber shell 13 connected in sequence. The top sealing shell 4 is detachably connected to the limiting sleeve 1 and the pressure-maintaining chamber shell 13, respectively, and can be threadedly connected. The inner tube is composed of an inflation joint 2, an air storage cylinder 5, a release valve shell 7 and a top sealing joint 17. When the inner tube moves axially along the outer tube, the gas release mechanism is triggered to release the high-pressure gas in the air storage cylinder 5. How the gas release mechanism blocks and releases the high-pressure gas in the air storage cylinder 5 will be described in detail below.

[0030] The embodiment of the present application provides a pressure compensation and valve closing drive device for a pressure-maintaining rope coring drill, comprising: an outer tube and an inner tube assembled in the outer tube, the top of the inner tube is a high-pressure gas storage cylinder, a gas release mechanism is located at the bottom of the high-pressure gas storage cylinder, the gas release mechanism is used to block and release the high-pressure gas in the high-pressure gas storage cylinder, an isolation piston is located below the gas release mechanism, the bottom of the isolation piston is a throttling cavity, a valve driving mechanism is arranged below the throttling cavity, the pressure-maintaining cavity is connected to the throttling cavity through a throttling and pressure compensation joint, a one-way valve is arranged on the throttling and pressure compensation joint, the isolation piston moves toward the throttling cavity under the push of high-pressure gas, drives the liquid in the throttling cavity to do work to drive the valve closing drive mechanism to close the sealing valve at the bottom of the pressure-maintaining cavity, and provides pressure compensation to the pressure-maintaining cavity through the throttling and pressure compensation joint. After the pressure-maintaining cavity collects the hydrate sample, the gas release mechanism releases the high-pressure gas to push the isolation piston to do work, provides driving power for closing the sealing valve of the pressure-maintaining cavity, and provides pressure compensation for the pressure-maintaining cavity, which can effectively prevent the decomposition of the hydrate sample in the pressure-maintaining cavity.

[0031] Based on the above embodiments, the high-pressure air cylinder of the embodiment of the present application includes an inflation connector 2, an air cylinder 5, an inflation valve plug 3 and a release valve core 9. The top of the air cylinder 5 is connected to the inflation connector 2, the release valve core 9 is plugged into the through hole at the bottom of the air cylinder 5, the inflation valve plug 3 is arranged in the inflation connector 2, and the through hole is provided with a hole seal.

[0032] The gas storage cylinder 5 in the embodiment of the present application is a cylindrical cavity, and the gas charging connector 2 is connected to the gas storage cylinder 5 by threads. The function of the gas charging valve plug 3 is to block the orifice of the gas charging connector 2 to prevent gas leakage. In addition, the through hole at the bottom of the gas storage cylinder 5 is provided with a hole seal to prevent gas leakage.

[0033] Furthermore, Figure 3 A cross-sectional view of a release valve core provided in an embodiment of the present application, such as Figure 3 As shown, the release valve core 9 includes a plunger 901 and a locking block. The plunger 901 is coaxially assembled on the top of the locking block. The plunger 901 is used to block the through hole at the bottom of the gas storage cylinder 5. The diameter of the locking block is larger than the diameter of the plunger 901. A gas release channel 902 is provided inside the locking block. The outer surface of the locking block is provided with a first locking groove 903 and a first annular sealing groove. The first annular sealing groove is equipped with a first annular seal 904. The first annular seal 904 is in contact with the release valve housing 7. When the plunger 901 is separated from the through hole at the bottom of the gas storage cylinder 5, the high-pressure gas is released through the gas release channel 902.

[0034] The diameter of the plunger 902 matches the diameter of the through hole at the bottom of the gas storage cylinder 5, and the locking block is arranged inside the release valve housing 7. The outer surface of the locking block is provided with a first annular sealing groove, and the first annular sealing member 904 installed in the first annular sealing groove abuts against the release valve housing 7, so as to allow the high-pressure gas in the gas storage cylinder 5 to be released smoothly through the gas release channel 902, and to prevent the high-pressure gas from leaking through the gap between the locking block and the release valve housing 7. Figure 3 As shown, the gas release channel 902 is divided into two ends. The gas release channel 902 close to the plunger 901 is a double-opening airway, one end of which is located on both sides of the plunger 901, and the gas release channel 902 away from the plunger 901 is a single airway, one end of which is connected to the other end of the double-opening airway.

[0035] Based on the above embodiments, the gas release mechanism of the embodiment of the present application includes a trigger sleeve 6, a release valve housing 7, a release valve lock block 8, a reset spring 10 and a limit sleeve 1. The upper part of the release valve housing 7 is threadedly connected to the lower part of the gas storage cylinder 5. The outer circumferential surface of the release valve housing 7 is sequentially sleeved with the trigger sleeve 6 and the reset spring 10. The top of the trigger sleeve 6 abuts against the gas storage cylinder 5 or the limit sleeve 1, and the bottom of the trigger sleeve 6 abuts against the top of the reset spring 10. A supporting boss is provided in the middle of the outer circumferential surface of the release valve housing 7, and the reset spring 10 The bottom of the release valve housing 7 abuts against the supporting boss, the side wall of the release valve housing 7 is provided with a locking block through hole, and a release valve locking block 8 is installed in the locking block through hole. A release groove is provided on the side of the trigger sleeve 6 close to the release valve housing 7. When the release valve locking block 8 is located in the first locking groove 903, the gas release mechanism is used to limit the release valve core 9 to enable the plunger 901 to be plugged with the through hole at the bottom of the gas storage cylinder 5. When the release valve locking block 8 is located in the release groove, the release valve core 9 moves downward under the action of the high-pressure gas to release the high-pressure gas through the gas release channel 902.

[0036] The outer cylindrical surface of the trigger sleeve 6 in the embodiment of the present application is uniformly distributed with axial flow channels. A release groove is provided on the inner side of the trigger sleeve 6 near the release valve housing 7. The release groove forms two sizes of cylindrical surfaces on the inner side of the trigger sleeve 6. The small-sized cylindrical surface is the radial limit surface of the release valve lock block 8 in the locked state, and the large-sized cylindrical surface (i.e., the side of the release groove) is the radial limit surface of the release valve lock block 8 in the released state. The trigger sleeve 6 is supported by the reset spring 10, and the upper end surface of the trigger sleeve 6 is in contact with the lower end of the gas storage cylinder 5 or the limit sleeve 1 for limit. Figure 1 In the embodiment, when the inner tube is located inside the outer tube, the upper end surface of the trigger sleeve 6 contacts and limits the lower end of the gas storage cylinder 5. At this time, the release valve lock block 8 is located in the first locking groove 903 provided on the outer surface of the release valve core 9 to limit the plunger 901 of the release valve core 9 in the through hole at the bottom of the gas storage cylinder 5; Figure 2In the process, the inner cylinder moves differentially relative to the outer cylinder, that is, the inner cylinder moves upward in the axial direction. When the inflation joint 2 at the top of the inner cylinder is located outside the outer cylinder, the entire inner cylinder moves upward, and the release valve housing 7 as a part of the inner cylinder moves upward relative to the trigger sleeve 6, thereby generating a downward force on the trigger sleeve 6. The trigger sleeve 6 compresses the return spring 10 and moves downward, so that the release valve lock block 8 enters the release groove inside the trigger sleeve 6, so that the entire release valve core 9 moves downward without the release valve lock block 8 limiting and under the action of high-pressure gas, so that the plunger 901 of the release valve core 9 is separated from the through hole in the air outlet tube, and the high-pressure gas is released through the gas release channel 902. The high-pressure gas pushes the isolation piston 11 at the bottom of the release valve core 9 to move downward. Specifically, the release valve housing 7 is a rotating body, the upper end of the release valve housing 7 is threadedly connected to the air storage cylinder 5, the middle of the outer peripheral surface of the release valve housing 7 is a supporting boss for the reset spring 10, the side wall of the release valve housing 7 can be provided with a plurality of locking block through holes, the locking block through holes can be square, and correspondingly, the release valve lock block 8 is a block body, and a boss can be provided in the middle of the release valve housing 7 to limit the release valve core 9 and prevent the release valve core 9 from moving down all the time. Further, Figure 4 A cross-sectional view of a release valve lock block provided in an embodiment of the present application, such as Figure 4 As shown, the side of the release valve lock block 8 facing the trigger sleeve 6 is a release contact surface 801, and the side of the release valve lock block 8 facing the release valve core 9 is a locking contact surface 802. The release contact surface 801 is a convex surface, and the locking contact surface 802 is a concave surface. The design of the release valve lock block 8 can effectively ensure the release or locking of the release valve core 9.

[0037] Based on the above embodiments, Figure 5 A cross-sectional view of an isolation piston provided in an embodiment of the present application, such as Figure 5As shown, the isolation piston 11 of the embodiment of the present application includes an isolation piston sleeve 1105, an inner bore piston rod 1101 and a locking nut 1106. The isolation piston sleeve 1105 is sleeved on the outer circumferential surface of the inner bore piston rod 1101. A limiting boss is provided on the top of the inner bore piston rod 1101. An external thread is provided at the tail of the inner bore piston rod 1101. The external thread cooperates with the internal thread of the locking nut 1106 to limit the isolation piston sleeve 1105 between the limiting boss and the locking nut 1106. A reset sealing surface and a limiting notch are provided on the outer circumferential surface of the inner bore piston rod 1101 from the limiting boss to the external thread in sequence. A second annular sealing groove is provided on the inner circumferential surface of the isolation piston sleeve 1105 near the inner bore piston rod 1101. A second annular sealing member 1102 is assembled in the second annular sealing groove. The inner diameter of the annular seal 1102 matches the outer diameter of the reset sealing surface of the inner bore piston rod 1101. The inner diameter of the second annular seal 1102 is larger than the outer diameter of the inner bore piston rod 1101 where the limiting groove is provided. When the locking nut 1106 is unlocked, the isolation piston sleeve 1105 moves toward the tail of the inner bore piston rod 1101 so that the second annular seal 1102 is located at the limiting groove. When the locking nut 1106 is locked, the isolation piston sleeve 1105 moves toward the head of the inner bore piston rod 1101 so that the second annular seal 1102 abuts against the reset sealing surface. The outer peripheral surface of the isolation piston sleeve 1105 is provided with a third annular sealing groove, and the third annular seal 1103 is assembled in the third annular sealing groove. The third annular seal 1103 abuts against the release valve housing 7.

[0038] In the embodiment of the present application, one end of the inner bore piston rod 1101 is a limiting boss, and the other end is provided with an external thread that matches the internal thread of the locking nut 1106. By adjusting the locking nut 1106, the isolation piston sleeve 1105 can move freely along the axial direction of the inner bore piston rod 1101, and the lower side of the limiting boss is a reset sealing surface with a limited length, and a limiting notch can be symmetrically arranged between the external thread and the reset sealing surface. The locking nut 1106 is locked, and the second annular seal 1102 abuts against the reset sealing surface. The isolation piston 11 is not connected up and down for isolating the high-pressure gas, so that the high-pressure gas pushes the isolation piston 11 to move downward; if the isolation piston 11 needs to be moved up and reset, since the outer cylinder is detachably connected, after the outer cylinder is disassembled, the locking nut 1106 is unlocked, and the second annular seal 1102 is located at the limiting notch. Since the inner diameter of the second annular seal 1102 is larger than the outer diameter of the inner bore piston rod 1101 provided with the limiting notch, after the isolation piston 11 is connected up and down, it is convenient to move the isolation piston 11 up and reset.

[0039] Furthermore, the isolation piston sleeve 1105 is also provided with a mounting hole, in which a limit screw 1104 is assembled, and a first limit step and a second limit step are sequentially provided along the length direction of the limit slot, so as to limit the limit screw 1104 between the first limit step and the second limit step, and when the limit screw 1104 abuts against the second limit step, the second annular seal 1102 is located at the limit slot, and when the limit screw 1104 abuts against the first limit step, the second annular seal 1102 is located at the reset sealing surface; wherein, the first limit step is close to the reset sealing surface, and the second limit step is close to the external thread. Through the cooperation of the limit screw 1104, the first limit step and the second limit step, the operation can be convenient for the staff, and the nut can be locked and unlocked to a more accurate degree when the nut is locked and unlocked.

[0040] Based on the above embodiments, the throttling chamber 16 of the embodiment of the present application is composed of a top seal 15, a top sealing joint 17 and a throttling and pressure compensation joint 20. The upper part of the top sealing joint 17 is threadedly connected to the lower part of the release valve housing 7, and the lower part of the top sealing joint 17 is connected to the throttling and pressure compensation joint 20. Both ends of the top sealing joint 17 are provided with mounting grooves for assembling the top seal 15. The middle part of the top sealing joint 17 is the outlet channel of the liquid in the throttling chamber 16. The top seal 15 is used to move axially along the outer cylinder in the inner cylinder to seal the top of the pressure maintaining chamber 21.

[0041] The throttling and pressure compensation joint 20 in the embodiment of the present application is threadedly connected to the sampling tube at the bottom, and a throttling hole is provided on the upper end face, connecting the throttling cavity 16 and the pressure-maintaining cavity 21. A one-way valve 19 is installed in the center of the lower end, and multiple flow channel holes are evenly distributed in the middle. The one-way valve 19 can prevent the sample in the pressure-maintaining cavity 21 from entering the throttling cavity 16, and also facilitates the downward movement of the isolation piston 11 to provide pressure compensation to the pressure-maintaining cavity 21 through the throttling hole of the throttling and pressure compensation joint 20. The top seal 15 is used to seal the top of the pressure-maintaining cavity 21 when the inner cylinder moves axially along the outer cylinder to prevent leakage of samples in the pressure-maintaining cavity 21 and pressure fluctuations.

[0042] Based on the above embodiments, the valve closing drive mechanism of the embodiment of the present application includes a claw lock sleeve 12, a pressure-maintaining chamber housing 13, a top sealing housing 4, a claw 14 and a pre-compression spring. Figure 6 A cross-sectional view of a spring claw lock sleeve provided in an embodiment of the present application, such as Figure 6As shown, the outer side of the claw lock sleeve 12 is a sealing boss 1201, an unlocking cylinder 1202 and a locking cylinder 1203 from top to bottom, the inner side of the claw lock sleeve 12 is a top sealing surface 1204, and the top sealing surface 1204 cooperates with the top sealing member 15 mentioned above. The upper part of the pressure-maintaining chamber housing 13 is threadedly connected with the top sealing housing 4, and a sealing cylinder and a second locking groove are sequentially arranged from the upper thread of the pressure-maintaining chamber housing 13 downward, and a sealing ring is arranged on the outer peripheral surface of the top sealing joint 17, and the sealing ring is located below the outlet channel to seal The ring abuts against the sealing cylinder of the pressure-maintaining chamber housing 13 and is located above the sealing boss 1201. The top of the spring claw 14 is an elastically deformable contact, which is located between the second locking groove and the unlocking cylinder 1202. The tail of the spring claw 14 extends to between the pressure-maintaining chamber housing 13 and the locking cylinder 1203 of the spring claw lock sleeve 12, and is connected to the closing valve cylinder 18. The closing valve cylinder 18 is connected to the sealing valve of the pressure-maintaining chamber 21. The unlocking cylinder sleeve is provided with a pre-stressed spring, and the two ends of the pre-stressed spring abut against the sealing boss 1201 and the contacts of the spring claw 14 respectively.

[0043] When the locking cylinder 1203 of the spring claw lock sleeve 12 supports the inner side of the contact of the spring claw 14, the spring claw 14 is suspended in the second locking groove of the pressure-maintaining chamber shell 13; when the unlocking cylinder 1202 of the spring claw lock sleeve 12 supports the inner side of the contact of the spring claw 14, the spring claw 14 is unlocked from the second locking groove of the pressure-maintaining chamber shell 13, and the spring claw lock sleeve 12 is driven by the high-pressure gas to move downward together with the spring claw 14 to close the sealing valve of the pressure-maintaining chamber 21; the lower end of the pre-stressed spring is supported by the radial end face of the contact of the spring claw 14, and the upper end of the pre-stressed spring supports the sealing boss 1201 of the spring claw lock sleeve 12, so that the entire valve closing drive mechanism remains in a locked state. In addition, a sealing ring is provided on the outer peripheral surface of the top sealing joint 17, and the sealing ring is located below the outlet channel. The sealing ring abuts against the sealing cylindrical surface of the pressure-maintaining chamber housing 13, which can prevent leakage of liquid in the throttling chamber 16, so that the liquid flows out through the outlet channel and smoothly pushes the entire valve closing drive mechanism downward to close the sealing valve at the bottom of the pressure-maintaining chamber 21.

[0044] In order to better understand the present application, the following describes the use of the pressure compensation and valve closing drive device of the pressure-maintaining rope coring drill.

[0045] After the pressure-maintaining rope coring drill is ready, the compressed gas is injected into the gas reservoir 3 through the gas charging joint 2. Figure 1 After sampling is completed, when the rope is pulled up, the inner and outer cylinders produce a differential motion, and the final state is as follows Figure 2The top seal 15 closes the top seal of the pressure-maintaining chamber 21, and at the same time, the top seal joint 17, the top seal 15, and the throttling and pressure compensation joint 20 form a throttling chamber 16, and the throttling chamber 16 is connected to the pressure-maintaining chamber 21; the trigger sleeve 6 is blocked by the limiting sleeve 1 and the release valve lock block 8 is displaced, and the release valve core 9 is unlocked and moved downward, and the compressed gas is released. The high-pressure gas pushes the isolation piston 11 to drive the liquid in the throttling chamber 16 to do work, on the one hand, pushing the claw lock sleeve 12 downward to unlock the claw 14, and together with the claw 14, driving the valve closing cylinder 18 downward to close the sealing valve at the bottom of the pressure-maintaining chamber 21, and on the other hand, providing pressure compensation for the pressure-maintaining chamber 21 through the throttling hole of the throttling and pressure compensation joint 20.

[0046] The pressure compensation and valve closing drive device of a pressure-maintaining rope coring drill provided in the present application can enable the pressure-maintaining rope sampling drill to rely on controllable driving force to timely close the sample pressure-maintaining chamber at the sampling position to achieve in-situ pressure maintenance; at the same time, it provides real-time and continuous pressure compensation for the sample pressure-maintaining chamber, maintains the pressure of the pressure-maintaining chamber greater than the in-situ pressure, and protects the hydrate sample from decomposition due to pressure changes; and the entire device can be restored quickly and efficiently after use.

[0047] The above is a detailed introduction to the pressure compensation and valve closing drive device of a pressure-maintaining rope coring drill provided by the present application. The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referred to each other. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

[0048] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements 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 statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

Claims

1. A pressure compensation and valve closing drive device for a pressure-maintaining rope coring drill, characterized in that: include: An outer cylinder and an inner cylinder assembled in the outer cylinder, the top of the inner cylinder is a high-pressure gas storage cylinder, a gas release mechanism is located at the bottom of the high-pressure gas storage cylinder, the gas release mechanism is used to block and release the high-pressure gas in the high-pressure gas storage cylinder, an isolation piston (11) is located below the gas release mechanism, the bottom of the isolation piston (11) is a throttling chamber (16), a valve drive mechanism is arranged below the throttling chamber (16), a pressure-maintaining chamber (21) is connected to the throttling chamber (16) through a throttling and pressure compensation joint (20), a one-way valve (19) is arranged on the throttling and pressure compensation joint (20), the isolation piston (11) moves toward the throttling chamber (16) under the push of the high-pressure gas, drives the liquid in the throttling chamber (16) to do work so as to drive the valve closing drive mechanism to close the sealing valve at the bottom of the pressure-maintaining chamber (21), and provides pressure compensation for the pressure-maintaining chamber (21) through the throttling and pressure compensation joint (20).

2. The pressure compensation and valve closing drive device for the pressure-maintaining rope coring drill according to claim 1, characterized in that: The high-pressure gas storage cylinder comprises an inflation joint (2), an air storage cylinder (5), an inflation valve plug (3) and a release valve core (9); the top of the air storage cylinder (5) is connected to the inflation joint (2); the release valve core (9) is plugged into a through hole at the bottom of the air storage cylinder (5); the inflation valve plug (3) is arranged in the inflation joint (2); and the through hole is provided with a hole seal.

3. The pressure compensation and valve closing drive device for the pressure-maintaining rope coring drill according to claim 2 is characterized in that: The outer cylinder is composed of a limiting sleeve (1), a top sealing shell (4) and a pressure-maintaining chamber shell (13) which are connected in sequence; the top sealing shell (4) is detachably connected to the limiting sleeve (1) and the pressure-maintaining chamber shell (13), respectively; the inner cylinder is composed of the inflation joint (2), the gas storage cylinder (5), a release valve shell (7) and a top sealing joint (17); when the inner cylinder moves axially along the outer cylinder, the gas release mechanism is triggered to release the high-pressure gas in the gas storage cylinder (5).

4. The pressure compensation and valve closing drive device for the pressure-maintaining rope coring drill according to claim 3 is characterized in that: The release valve core (9) comprises a plunger (901) and a locking block. The plunger (901) is coaxially assembled on the top of the locking block. The plunger (901) is used to block the through hole at the bottom of the gas storage cylinder (5). The diameter of the locking block is larger than the diameter of the plunger (901). A gas release channel (902) is arranged inside the locking block. The outer surface of the locking block is provided with a first locking groove (903) and a first annular sealing groove. The first annular sealing groove is equipped with a first annular sealing member (904). The first annular sealing member (904) is in contact with the release valve housing (7). When the plunger (901) is separated from the through hole at the bottom of the gas storage cylinder (5), the high-pressure gas is released through the gas release channel (902).

5. The pressure compensation and valve closing drive device for the pressure-maintaining rope coring drill according to claim 4, characterized in that: The gas release mechanism comprises a trigger sleeve (6), a release valve housing (7), a release valve locking block (8), a reset spring (10) and a limit sleeve (1); the upper portion of the release valve housing (7) is threadedly connected to the lower portion of the gas storage cylinder (5); the outer circumferential surface of the release valve housing (7) is sleeved with the trigger sleeve (6) and the reset spring (10) in sequence; the top of the trigger sleeve (6) abuts against the gas storage cylinder (5) or the limit sleeve (1); the bottom of the trigger sleeve (6) abuts against the top of the reset spring (10); a supporting boss is provided in the middle of the outer circumferential surface of the release valve housing (7); the bottom of the reset spring (10) abuts against the The supporting boss is abutted, a locking block through hole is provided on the side wall of the release valve housing (7), a release valve locking block (8) is installed in the locking block through hole, and a release groove is provided on the side of the trigger sleeve (6) close to the release valve housing (7). When the release valve locking block (8) is located in the first locking groove (903), the gas release mechanism is used to limit the release valve core (9) so that the plunger (901) is plugged into the through hole at the bottom of the gas storage cylinder (5). When the release valve locking block (8) is located in the release groove, the release valve core (9) moves downward under the action of the high-pressure gas, so that the high-pressure gas is released through the gas release channel (902).

6. The pressure compensation and valve closing drive device for the pressure-maintaining rope coring drill according to claim 3, characterized in that: The isolation piston (11) comprises an isolation piston sleeve (1105), an inner bore piston rod (1101) and a locking nut (1106). The isolation piston sleeve (1105) is sleeved on the outer circumference of the inner bore piston rod (1101). The top of the inner bore piston rod (1101) is provided with a limiting boss. The tail of the inner bore piston rod (1101) is provided with an external thread, which cooperates with the internal thread of the locking nut (1106) to lock the isolation piston. The plug sleeve (1105) is limited between the limiting boss and the locking nut (1106); the outer circumferential surface of the inner hole piston rod (1101) is provided with a reset sealing surface and a limiting notch in sequence from the limiting boss to the external thread; the inner circumferential surface of the isolation piston sleeve (1105) close to the inner circumferential surface of the inner hole piston rod (1101) is provided with a second annular sealing groove; a second annular sealing member (1102) is installed in the second annular sealing groove; the second annular sealing member (1102) is provided with a second annular sealing member (1103); the second annular sealing member (1104) is provided with a second annular sealing member (1105); the second annular sealing member (1104) is provided with a second annular sealing member (1105); the second annular sealing member (1103) is provided with a second annular sealing member (1103 ... 02) matches the outer diameter of the inner bore piston rod (1101) at which the reset sealing surface is provided, the inner diameter of the second annular seal (1102) is larger than the outer diameter of the inner bore piston rod (1101) at which the limiting groove is provided, when the locking nut (1106) is unlocked, the isolation piston sleeve (1105) moves toward the tail of the inner bore piston rod (1101) so that the second annular seal (1102) is located at the limiting groove, when the locking nut (1106) is locked, the isolation piston sleeve (1105) moves toward the head of the inner bore piston rod (1101) so that the second annular seal (1102) abuts against the reset sealing surface, the outer peripheral surface of the isolation piston sleeve (1105) is provided with a third annular sealing groove, a third annular seal (1103) is assembled in the third annular sealing groove, and the third annular seal (1103) abuts against the release valve housing (7).

7. The pressure compensation and valve closing drive device for the pressure-maintaining rope coring drill according to claim 6, characterized in that: The isolation piston sleeve (1105) is also provided with a mounting hole, in which a limiting screw (1104) is assembled. A first limiting step and a second limiting step are sequentially provided along the length direction of the limiting slot to limit the limiting screw (1104) between the first limiting step and the second limiting step. When the limiting screw (1104) abuts against the second limiting step, the second annular seal (1102) is located at the limiting slot. When the limiting screw (1104) abuts against the first limiting step, the second annular seal (1102) is located at the reset sealing surface.

8. The pressure compensation and valve closing drive device for the pressure-maintaining rope coring drill according to claim 3, characterized in that: The throttling cavity (16) is composed of a top seal (15), a top seal joint (17) and a throttling and pressure compensation joint (20). The upper part of the top seal joint (17) is threadedly connected to the lower part of the release valve housing (7), and the lower part of the top seal joint (17) is connected to the throttling and pressure compensation joint (20). Both ends of the top seal joint (17) are provided with mounting grooves for assembling the top seal (15). The middle part of the top seal joint (17) is the outlet channel of the liquid in the throttling cavity (16). The top seal (15) is used to move axially along the outer cylinder in the inner cylinder to seal the top of the pressure-maintaining cavity (21).

9. The pressure compensation and valve closing drive device for the pressure-maintaining rope coring drill according to claim 8, characterized in that: The valve closing drive mechanism comprises a spring claw lock sleeve (12), a pressure-maintaining chamber shell (13), a top sealing shell (4), a spring claw (14) and a pre-stressed spring. The outer side of the spring claw lock sleeve (12) is a sealing boss (1201), an unlocking cylinder (1202) and a locking cylinder (1203) from top to bottom. The inner side of the spring claw lock sleeve (12) is a top sealing surface (1204). The top sealing surface (1204) cooperates with the top sealing member (15). The upper part of the pressure-maintaining chamber shell (13) is threadedly connected to the top sealing shell (4). A sealing cylinder and a second locking groove are sequentially arranged from the upper thread of the pressure-maintaining chamber shell (13) downward. The outer peripheral surface of the top sealing joint (17) is provided with a sealing ring. The sealing ring is located at the Below the outlet channel, the sealing ring abuts against the sealing cylinder of the pressure-maintaining chamber shell (13) and is located above the sealing boss (1201). The top of the spring claw (14) is an elastically deformable contact, and the contact is located between the second locking groove and the unlocking cylinder (1202). The tail of the spring claw (14) extends between the pressure-maintaining chamber shell (13) and the locking cylinder (1203) of the spring claw lock sleeve (12), and is connected to the closing valve cylinder (18). The closing valve cylinder (18) is connected to the sealing valve of the pressure-maintaining chamber (21). The unlocking cylinder (1202) is sleeved with the pre-stressed spring, and the two ends of the pre-stressed spring abut against the sealing boss (1201) and the contacts of the spring claw (14) respectively.

10. The pressure compensation and valve closing drive device for the pressure-maintaining rope coring drill according to claim 5, characterized in that: The side of the release valve locking block (8) facing the trigger sleeve (6) is a release contact surface (801), and the side of the release valve locking block (8) facing the release valve core (9) is a locking contact surface (802); the release contact surface (801) is a convex surface, and the locking contact surface (802) is a concave surface.

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