Thin film perforating device, liquefied gas storage and transportation tank and ship for transporting liquefied gas

Abstract

The application provides a film perforating device, a liquefied gas storage and transportation tank and a ship for transporting liquefied gas, comprising a guide mechanism, a perforating mechanism, a secondary impact mechanism and a lifting mechanism; the guide mechanism comprises a guide cylinder, the perforating mechanism slides and falls along the guide cylinder; the lifting mechanism is connected with the perforating mechanism, and the lifting mechanism is used for lifting the perforating mechanism; the perforating mechanism comprises a counterweight column and a perforating head, the perforating head is used for piercing a film, and the perforating head is in sliding connection with the counterweight column; the secondary impact mechanism comprises a locking assembly and a pushing piece, the pushing piece is used for applying a pushing force to the perforating head, the locking assembly is used for locking the position of the perforating head, and the locking of the perforating head is released after the perforating head completes the first film piercing action. The application can improve the piercing effect and ensure the reliability of film perforation.

Description

Technical Field

[0001] This application relates to the technical field of membrane perforation for liquefied natural gas tanks, and more particularly to a membrane perforation device, a liquefied gas storage and transportation tank, and a ship for transporting liquefied gas. Background Technology

[0002] Tanks used for transporting or storing liquefied natural gas typically employ a sealed and insulated structure. The tank wall generally consists of a secondary insulation barrier, a secondary sealing membrane, a primary insulation barrier, and a primary sealing membrane, arranged sequentially from the outside to the inside. The primary sealing membrane is in direct contact with the liquefied natural gas inside the tank and is used to prevent liquefied natural gas from leaking into the insulation layer. The secondary sealing membrane serves as a second line of defense, further ensuring the reliability of the seal.

[0003] During actual use of storage tanks, the primary sealing membrane may break due to material aging, assembly defects, or changes in external loads, allowing liquefied natural gas (LNG) to seep into the primary insulation barrier. When tank maintenance is required, the LNG must typically be emptied first. However, during this emptying process, the LNG that has already seeped into the primary insulation barrier is difficult to remove, creating a pressure imbalance between the primary insulation barrier and the tank's internal space. The LNG trapped in the insulation layer pushes the primary sealing membrane further into the tank and may also vaporize due to the rising temperature inside the tank. The pressure generated by vaporization continues to increase, potentially causing deformation or even tearing of the primary sealing membrane, further damaging the integrity of the tank structure.

[0004] To address the aforementioned issues, the relevant technology involves installing a raised cylinder on the bottom wall of the storage tank. The space between the raised cylinder and the membrane layer on the bottom wall of the tank is open, and a thin membrane is fixedly connected to the top of the raised cylinder, sealing the top of the cylinder. A perforation device is then installed to manually puncture the membrane, creating a hole that allows liquefied natural gas trapped in the membrane layer on the bottom wall of the tank to enter the raised cylinder. The liquefied natural gas is then pumped out from the raised cylinder, thus preventing damage to the tank wall due to pressure imbalance. The perforation device includes a weighted perforating component that moves along a predetermined path under its own weight, impacting and puncturing the membrane, thereby creating a discharge channel.

[0005] However, in practical use, the perforation device in the relevant technology can often only achieve a one-time puncture action. That is, the perforation component can only complete one impact. If the puncture fails to form a sufficiently large or penetrating hole in the membrane, it will lead to problems such as poor puncture effect and obstructed discharge channel, which will affect the discharge efficiency of liquefied natural gas leaks. It may even require readjustment of the perforation device to perform perforation again, resulting in cumbersome operation and low efficiency. Summary of the Invention

[0006] To improve the puncture effect and ensure the reliability of membrane perforation, this application provides a membrane perforation device, a liquefied gas storage and transportation tank, and a ship for transporting liquefied gas.

[0007] In a first aspect, this application provides a thin film perforation device, which adopts the following technical solution: A thin film perforation device includes a guiding mechanism, a perforation mechanism, a secondary impact mechanism, and a lifting mechanism; the guiding mechanism includes a guide cylinder, and the perforation mechanism slides down along the guide cylinder; the lifting mechanism is connected to the perforation mechanism and is used to lift the perforation mechanism. The piercing mechanism includes a counterweight column and a piercing head. The piercing head is used to pierce the film and is slidably connected to the counterweight column. The secondary impact mechanism includes a locking component and a pushing component. The pushing component is used to apply a pushing force to the piercing head, and the locking component is used to lock the position of the piercing head and release the locking of the piercing head after the piercing head completes the first film piercing action.

[0008] By adopting the above technical solution, the guide cylinder guides the descent path of the piercing mechanism, ensuring that the piercing mechanism accurately falls to the position of the film to be pierced. After the piercing head completes the first piercing action, the locking component releases the locking of the piercing head, and the pushing component then applies a thrust to the piercing head, driving the piercing head to make a secondary impact on the film. This further expands or completes the piercing based on the first piercing, effectively improving the reliability of piercing the film and avoiding the problems of incomplete piercing and subsequent poor drainage caused by relying on a single piercing. The lifting mechanism facilitates the repositioning of the piercing mechanism, making the device reusable.

[0009] Optionally, the locking assembly includes a bearing groove, a sliding block, and a sliding rod; the bearing groove is connected to the counterweight column, the sliding block is slidably connected to the bearing groove, and the perforated head is connected to the sliding block; the pushing member is an elastic member, which is connected to the bearing groove and the sliding block respectively, and the elastic member applies elastic force to the sliding block; The sliding block has a groove, one end of the sliding rod is hinged to the bearing groove, and the other end of the sliding rod is slidably connected in the groove; the groove is provided with a locking point and a pop-out point. When the sliding rod slides into the locking point, the sliding rod locks the position of the sliding block; when the sliding rod slides into the pop-out point, the sliding block pops out.

[0010] By adopting the above technical solution, the locking and releasing of the sliding block and the perforating head are achieved by switching the position of the sliding rod between the locking point and the ejection point within the sliding groove. The structure is simple and reliable. The reaction force experienced by the perforating head during the piercing of the film directly drives the sliding rod from the locking point to the ejection point, thereby automatically triggering the elastic element to release its elastic force. The elastic element then pushes the perforating head for a secondary impact. The entire process requires no additional power supply or electrical control, improving the applicability and reliability of the device in environments without power.

[0011] Optionally, the circumferential wall of the counterweight column is connected to a guide wing.

[0012] By adopting the above technical solution, the guide wing limits and guides the falling posture of the counterweight column in the guide cylinder, preventing the perforation mechanism from swaying or shaking during the falling process, ensuring the stability of the falling path of the perforation mechanism, and thus improving the accuracy of the puncture position.

[0013] Optionally, the inner wall of the guide cylinder is provided with a spiral guide groove, the guide wing is spiral in shape, and the guide wing slides in conjunction with the guide groove.

[0014] By adopting the above technical solution, the spiral guide groove and the spiral guide wing cooperate with each other, so that the piercing mechanism rotates and falls along the spiral trajectory under its own gravity. At the moment of contact and piercing the film, the piercing head has a combined force of rotational cutting and axial impact, thereby further improving the effect of piercing the film.

[0015] Optionally, the lifting mechanism includes a pull rope, a turntable, and a sealing plate; the turntable is rotatably connected to the counterweight column, and the pull rope is connected to the turntable; the sealing plate passes through the top of the guide cylinder, and the sealing plate is engaged with the perforation mechanism.

[0016] By adopting the above technical solution, the turntable and the counterweight column are rotatably connected, allowing the counterweight column to rotate freely during the spiral descent without causing the pull rope to become tangled or twisted, thus ensuring the smooth spiral descent of the perforation mechanism. The sealing plate engages with the perforation mechanism, securing it to the top of the guide cylinder, facilitating the installation and positioning of the device and the subsequent release of the perforation mechanism to complete the piercing operation.

[0017] Optionally, the guiding mechanism further includes a baffle and a buffer. The baffle is connected to the bottom end of the guide cylinder and is used to limit the perforation mechanism. The buffer is disposed between the baffle and the counterweight column.

[0018] By adopting the above technical solution, the baffle limits the falling end position of the perforation mechanism, and the buffer is set between the baffle and the counterweight column, which can buffer and absorb the impact force generated when the perforation mechanism falls, and extend the service life of the perforation mechanism.

[0019] Optionally, a spiral plate is connected to the circumferential wall of the perforated head.

[0020] By adopting the above technical solution, the spiral plate on the circumferential wall of the perforating head can generate a rotary cutting effect on the film during the process of the perforating head piercing the film, which further improves the piercing effect of the perforating head on the film.

[0021] Optionally, the perforated head is stepped.

[0022] By adopting the above technical solution, the perforating head penetrates the membrane step by step in a stepped structure, which can gradually enlarge the perforation diameter while piercing the membrane, so that the subsequently permeated liquid natural gas can be smoothly discharged from the perforation, thus improving the drainage efficiency.

[0023] Secondly, this application also provides a liquefied gas storage and transportation tank, including the aforementioned membrane perforation device.

[0024] Thirdly, this application also provides a ship for transporting liquefied gas, including a hull and a liquefied gas storage tank as described above disposed in the hull.

[0025] In summary, this application includes at least one of the following beneficial effects: 1. By setting a locking component and a pushing component, a secondary impact on the perforating head is automatically or controllably triggered after the perforating head completes the first piercing action of the film, which effectively improves the problem of poor piercing effect caused by only one piercing in related technologies and improves the reliability of film perforation. 2. Through the sliding cooperation of the spiral guide groove and the spiral guide wing, the piercing mechanism generates a synchronous rotational motion during the falling process, so that the piercing head has a combined effect of rotational cutting and axial impact, which further improves the effect of piercing the film. 3. By using baffles and buffers in combination, the falling stroke of the perforation mechanism is limited and buffered, reducing equipment wear and extending the service life of the device; 4. By setting a spiral plate on the surface of the perforation head and designing the perforation head as a stepped structure, the effects of rotary cutting efficiency enhancement and gradual increase in aperture are achieved, which is beneficial to improving the puncture effect and facilitating the rapid discharge of liquefied natural gas from the perforation. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the thin film perforation device installed inside the tank according to an embodiment of this application; Figure 2 This is a cross-sectional structural schematic diagram of the thin film perforation device according to an embodiment of this application; Figure 3 yes Figure 2 A magnified structural diagram of part A in the middle; Figure 4 This is a schematic diagram of the perforation mechanism according to an embodiment of this application; Figure 5 This is a schematic diagram of the secondary impact mechanism in an embodiment of this application; Figure 6 yes Figure 2 A magnified structural diagram of part B in the middle section; Figure 7 This is a structural schematic diagram of the ship and liquefied gas storage and transportation tank according to an embodiment of this application.

[0027] Explanation of reference numerals in the attached drawings: 1. Guiding mechanism; 11. Guide cylinder; 12. Baffle; 13. Buffer component; 2. Perforation mechanism; 21. Counterweight column; 22. Guide wing; 23. Perforation head; 24. Spiral plate; 3. Secondary impact mechanism; 31. Locking assembly; 311. Bearing groove; 312. Sliding block; 3121. Slide groove; 3122. Locking point; 3123. Pop-out point; 313. Sliding rod; 32. Pushing component; 321. Elastic component; 4. Lifting mechanism; 41. Pull rope; 42. Turntable; 43. Sealing plate; 8. Shell; 9. Liquefied gas storage and transportation tank; 100. Protruding cylinder. Detailed Implementation

[0028] The following combination Figures 1 to 7 This application will be described in further detail.

[0029] This application provides a thin film perforation device.

[0030] refer to Figure 1 and Figure 2A membrane perforation device includes a guiding mechanism 1, a perforation mechanism 2, a secondary impact mechanism 3, and a lifting mechanism 4. A raised cylinder 100 is installed on the inner bottom wall of a liquefied gas storage tank 9. The space between the raised cylinder 100 and the membrane layer on the inner bottom wall of the liquefied gas storage tank 9 is connected. A membrane is fixedly connected to the top of the raised cylinder 100, and the membrane seals the top of the raised cylinder 100. The guiding mechanism 1 includes a hollow cylindrical guide cylinder 11, which is arranged vertically. The guide cylinder 11 passes through the top wall of the liquefied gas storage tank 9 and is fixedly connected to the liquefied gas storage tank 9. The guide cylinder 11 is located above the membrane to be perforated, and a through-flow falling channel is formed inside the guide cylinder 11. The piercing mechanism 2 is housed inside the guide cylinder 11 and can slide vertically down along the inner wall of the guide cylinder 11. The guide cylinder 11 limits the falling path and posture of the piercing mechanism 2, ensuring that the piercing mechanism 2 accurately falls to the piercing position on the film and avoiding inaccurate piercing position due to deviation of the falling path. The lifting mechanism 4 is connected to the piercing mechanism 2 and is used to lift the piercing mechanism 2 to the upper part of the guide cylinder 11, so that the piercing mechanism 2 has sufficient falling height to accumulate kinetic energy. It also facilitates the re-lifting of the piercing mechanism 2 after the piercing action is completed, enabling the device to be reused.

[0031] refer to Figure 3 and Figure 4 The perforation mechanism 2 includes a counterweight column 21 and a perforation head 23. The counterweight column 21 is cylindrical in shape, and its outer diameter is smaller than the inner diameter of the guide cylinder 11, so that the counterweight column 21 can fall along the guide cylinder 11. The perforation head 23 is located at the lower end of the counterweight column 21. The perforation head 23 can move relative to the counterweight column 21 by a certain stroke. The perforation head 23 is slidably connected to the counterweight column 21, so that the perforation head 23 can extend or retract vertically relative to the counterweight column 21. The secondary impact mechanism 3 is located between the counterweight column 21 and the piercing head 23. When the counterweight column 21 carries the piercing head 23 down along the guide cylinder 11 and comes into contact with the film, the piercing head 23 first impacts the film under the impact force converted from the weight of the counterweight column 21. After the first puncture is completed, the secondary impact mechanism 3 is triggered, which drives the piercing head 23 to extend further downward relative to the counterweight column 21 and make a second impact on the same position of the film. This further enlarges or penetrates the initial hole formed by the first impact, thus improving the puncture effect.

[0032] refer to Figure 3 and Figure 5The secondary impact mechanism 3 includes a locking component 31 and a pusher 32. In this embodiment, the locking component 31 and the pusher 32 constitute a press-type self-locking pop-out structure (or push-push structure). The pusher 32 is used to apply a thrust toward the film direction to the perforating head 23, and the locking component 31 is used to lock the position of the perforating head 23 relative to the counterweight column 21 before the secondary impact action is triggered, so as to prevent the thrust of the pusher 32 from being released prematurely.

[0033] refer to Figure 3 and Figure 5 The locking assembly 31 includes a bearing groove 311, a sliding block 312, and a sliding rod 313. The bearing groove 311 is located inside the lower end of the counterweight column 21 and is fastened to the counterweight column 21 by bolts. An accommodating space is formed inside the bearing groove 311, and the sliding block 312 is accommodated within this space. The sliding block 312 is slidably connected to the inner wall of the bearing groove 311 and can reciprocate vertically relative to the bearing groove 311. A perforated head 23 is fixedly connected to the sliding block 312, allowing the perforated head 23 to move relative to the counterweight column 21 as the sliding block 312 slides. In this embodiment, the pusher 32 is preferably a spring. The two ends of the pusher 32 are fixedly connected to the inner wall of the bearing groove 311 and the upper end face of the sliding block 312, respectively. When the pusher 32 is compressed, it applies a downward elastic force to the sliding block 312, thereby driving the sliding block 312 and the perforated head 23 to have a downward popping motion tendency.

[0034] refer to Figure 3 and Figure 5 The sliding block 312 has a labyrinth-shaped groove 3121 on its side wall. One end of the sliding rod 313 is hinged to the side wall of the bearing groove 311 via a pin, allowing the sliding rod 313 to rotate around the hinge point. The other end of the sliding rod 313 extends into the groove 3121 of the sliding block 312 and slides against the groove wall. The groove 3121 has a locking point 3122 and a pop-out point 3123, which correspond to two different position areas on the groove 3121. Before using the device, the operator manually pushes the perforating head 23 upward, causing the sliding block 312 to push the elastic element 321 upward. At the same time, the end of the sliding rod 313 slides into the locking point 3122 of the sliding groove 3121. At this time, the locking point 3122 and the sliding rod 313 lock the position of the sliding block 312, keeping the sliding block 312 in the position of the compressed spring and preventing it from sliding down under the action of the spring force, thereby locking the position of the perforating head 23. During this process, the elastic element 321 is always in a compressed energy storage state.

[0035] refer to Figure 3 and Figure 5When the entire perforation mechanism 2 falls along the guide cylinder 11, the lower end of the perforation head 23 first contacts and collides with the film, completing the first impact. The perforation head 23 receives a reaction force from the film, causing the sliding block 312 to displace relative to the bearing groove 311. This displacement drives the end of the sliding rod 313 to slide along the groove 3121, moving from the locking point 3122 to the ejection point 3123. When the end of the sliding rod 313 enters the ejection point 3123, the sliding block 312 immediately loses its limiting constraint, and the elastic element 321 releases its stored elastic potential energy, pushing the sliding block 312 and the perforation head 23 to rapidly eject downwards relative to the counterweight column 21, thus puncturing the film a second time. The locking and releasing process of this application relies on the relative motion of the mechanical structure, requiring no external power supply or electrical control, thus improving the applicability and operational reliability of the perforation device.

[0036] refer to Figure 3 and Figure 4 A guide wing 22 is fixedly connected to the circumferential outer wall of the counterweight column 21. The guide wing 22 is spiral in shape. A spiral guide groove is opened on the inner wall of the guide cylinder 11. The outer edge of the guide wing 22 is accommodated in the guide groove, and the guide wing 22 and the groove wall of the guide groove form a sliding fit relationship. By reasonably setting the helix angle of the guide groove, the perforation mechanism 2 can smoothly move up or down. When the perforation mechanism 2 falls along the guide cylinder 11 under its own gravity, since the guide wing 22 is restricted to move within the spiral guide groove, the perforation mechanism 2 generates rotational motion while realizing vertical downward displacement, thus forming a spiral falling trajectory. This means that when the perforation head 23 contacts the film, in addition to the axial impact force, it also has a rotational cutting component around its own axis. The combined action of these two forces on the film surface can more effectively damage the film compared to a simple linear impact, thus improving the piercing effect of the perforation head 23 on the film.

[0037] refer to Figure 3 and Figure 4 The lifting mechanism 4 includes a pull rope 41, a turntable 42, and a sealing plate 43. The turntable 42 is rotatably connected to the top of the counterweight column 21, and can rotate freely relative to the counterweight column 21 without rotating synchronously with it. One end of the pull rope 41 is fixedly connected to the turntable 42, and the other end extends to the outside of the guide cylinder 11, allowing the operator to manually pull or use a winch to retract and release the piercing mechanism 2 back to the top of the guide cylinder 11. Because the turntable 42 and the counterweight column 21 are rotatably connected, when the counterweight column 21 rotates around its axis and falls under the action of the spiral guide groove, the turntable 42 does not rotate with the counterweight column 21, thus preventing the pull rope 41 from twisting and tangling with the counterweight column 21, ensuring the smooth spiral descent of the piercing mechanism 2.

[0038] refer to Figure 2 and Figure 3 A sealing plate 43 is inserted through the top opening of the guide cylinder 11. The sealing plate 43 has a locking groove that matches the shape of the piercing mechanism 2. After the piercing mechanism 2 is lifted to the top of the guide cylinder 11, it is inserted into the sealing plate 43. The sealing plate 43 holds and fixes the counterweight column 21, thereby suspending and fixing the piercing mechanism 2 to the top of the guide cylinder 11. This facilitates the installation of the device and the subsequent release of the piercing mechanism 2 to complete the piercing operation. When it is necessary to release the piercing mechanism 2, the sealing plate 43 is pulled out, allowing the piercing mechanism 2 to fall.

[0039] refer to Figure 2 and Figure 6 The guide mechanism 1 also includes a baffle 12, which is fixedly connected to the bottom end of the guide cylinder 11. The baffle 12 has a through hole for the perforating head 23 to pass through. The size of the through hole is smaller than the outer diameter of the counterweight column 21, thus allowing the baffle 12 to limit and block the falling end position of the counterweight column 21, preventing the perforating mechanism 2 from detaching from the guide cylinder 11. A buffer 13 is disposed between the baffle 12 and the counterweight column 21. The buffer 13 is an elastic pad. In this embodiment, the buffer 13 is fixedly connected to the upper surface of the baffle 12; in other embodiments of this embodiment, the buffer 13 is fixedly connected to the lower end face of the counterweight column 21. When the perforating mechanism 2 falls to the end of its stroke, the buffer 13 can absorb part of the impact energy generated by the perforating mechanism 2 hitting the baffle 12, reducing the rigid collision between the counterweight column 21 and the baffle 12. Furthermore, the baffle 12 and the buffer 13 do not affect the perforating operation of the perforating head 23 on the film.

[0040] refer to Figure 3 and Figure 4 A spiral plate 24 is fixedly connected to the circumferential outer wall of the piercing head 23. During the process of the piercing head 23 piercing the film, as the piercing mechanism 2 rotates and falls, the spiral plate 24 can generate a rotational cutting effect on the film around the piercing position of the piercing head 23, further assisting in destroying the structural integrity of the film and improving the piercing efficiency and piercing effect of the piercing head 23.

[0041] refer to Figure 3 and Figure 4 The perforating head 23 is stepped in shape. When the perforating head 23 penetrates the membrane, the smallest diameter tip first pierces the membrane to form an initial hole. As the perforating head 23 penetrates further, subsequent steps with gradually increasing diameters pass through the initial hole, thereby progressively enlarging the hole. This stepped structure design helps to increase the perforation area on the membrane, facilitating the subsequent extraction of permeated liquefied natural gas through the perforation channel.

[0042] The implementation principle of the film perforation device in this application embodiment is as follows: When using the film perforation device, the perforation head 23 is first moved to the locked position relative to the counterweight column 21, so that the pushing member 32 is in an energy storage state. During operation, the locking limit of the sealing plate 43 is released, and the perforation mechanism 2 falls along the guide cylinder 11 under its own gravity. The spiral guide wing 22 of the counterweight column 21 and the spiral guide groove on the inner wall of the guide cylinder 11 cooperate with each other, causing the perforation mechanism 2 to rotate and fall, causing the perforation head 23 to impact the film in a combined impact and shearing manner. The reaction force generated by the perforation head 23 touching the film causes the locking component 31 to release the lock on the perforation head 23, and the pushing member 32 releases its elastic force to drive the perforation head 23 to further eject relative to the counterweight column 21, applying a secondary impact to the same position of the film, thereby further expanding or penetrating the perforation on the basis of the initial puncture. After the perforation mechanism 2 punctures the membrane at the top of the protruding cylinder 100, liquefied natural gas can be subsequently extracted from the protruding cylinder 100, reducing the possibility of liquefied natural gas remaining between the membrane layers on the bottom wall of the liquefied gas storage and transportation tank 9. When the perforation mechanism 2 falls to the end of its stroke, it is limited by the baffle 12 and the buffer 13 absorbs energy to avoid impact damage. After the puncture is completed, the perforation mechanism 2 is lifted and reset by the lifting mechanism 4, thus achieving reliable perforation of the membrane and facilitating the smooth discharge of the perforated liquefied natural gas through the perforation.

[0043] This embodiment also provides a ship, including a hull 8 and a liquefied gas storage and transportation tank 9 disposed in the hull 8 as described above.

[0044] refer to Figure 7 A cross-sectional view of a ship used for transporting liquefied gas (LNG) coolants shows a liquefied gas storage tank 9, typically prismatic in shape, mounted within the ship's hull 8. The wall of the anti-sloshing LNG storage tank 9 may include a primary sealing membrane, a secondary sealing membrane, and two insulating layers. The primary sealing membrane is for contact with the LNG contained in the tank. The secondary sealing membrane is disposed between the primary sealing membrane and the ship's hull. The two insulating layers are respectively disposed between the primary and secondary sealing membranes, and between the secondary sealing membrane and the hull. Furthermore, a device / unloading pipe located on the ship's upper deck can be connected to an offshore or port terminal via suitable connectors to transfer LNG between the cargo ship and the LNG storage tank 9.

[0045] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A thin film perforation device, characterized in that: It includes a guiding mechanism (1), a perforating mechanism (2), a secondary impact mechanism (3), and a lifting mechanism (4); the guiding mechanism (1) includes a guide cylinder (11), and the perforating mechanism (2) slides down along the guide cylinder (11); the lifting mechanism (4) is connected to the perforating mechanism (2), and the lifting mechanism (4) is used to lift the perforating mechanism (2). The piercing mechanism (2) includes a counterweight column (21) and a piercing head (23). The piercing head (23) is used to pierce the film, and the piercing head (23) is slidably connected to the counterweight column (21). The secondary impact mechanism (3) includes a locking component (31) and a pushing component (32). The pushing component (32) is used to apply a pushing force to the piercing head (23), and the locking component (31) is used to lock the position of the piercing head (23). After the piercing head (23) completes the first film piercing action, the locking of the piercing head (23) is released. The locking assembly (31) includes a bearing groove (311), a sliding block (312), and a sliding rod (313); the bearing groove (311) is connected to the counterweight column (21), the sliding block (312) is slidably connected to the bearing groove (311), and the perforated head (23) is connected to the sliding block (312); the pushing member (32) is an elastic member (321), the elastic member (321) is connected to the bearing groove (311) and the sliding block (312) respectively, and the elastic member (321) applies elastic force to the sliding block (312); The sliding block (312) has a groove (3121). One end of the sliding rod (313) is hinged to the bearing groove (311), and the other end of the sliding rod (313) is slidably connected in the groove (3121). The groove (3121) is provided with a locking point (3122) and a pop-out point (3123). When the sliding rod (313) slides into the locking point (3122), the sliding rod (313) locks the position of the sliding block (312). When the sliding rod (313) slides into the pop-out point (3123), the sliding block (312) pops out.

2. The thin film perforation device according to claim 1, characterized in that: The counterweight column (21) has a guide wing (22) connected to its circumferential wall.

3. The thin film perforation device according to claim 2, characterized in that: The inner wall of the guide cylinder (11) is provided with a spiral guide groove, the guide wing (22) is spiral, and the guide wing (22) slides in conjunction with the guide groove.

4. The thin film perforation device according to claim 3, characterized in that: The lifting mechanism (4) includes a pull rope (41), a turntable (42) and a sealing plate (43); the turntable (42) is rotatably connected to the counterweight column (21), and the pull rope (41) is connected to the turntable (42); the sealing plate (43) is inserted through the top of the guide cylinder (11), and the sealing plate (43) is engaged with the perforation mechanism (2).

5. The thin film perforation device according to claim 1, characterized in that: The guide mechanism (1) further includes a baffle (12) and a buffer (13). The baffle (12) is connected to the bottom end of the guide cylinder (11). The baffle (12) is used to limit the perforation mechanism (2). The buffer (13) is disposed between the baffle (12) and the counterweight column (21).

6. The thin film perforation device according to claim 1, characterized in that: The circumferential wall of the perforated head (23) is connected to a spiral plate (24).

7. A thin film perforation device according to claim 1, characterized in that: The perforated head (23) is stepped.

8. A liquefied gas storage and transportation tank, characterized in that, Includes the thin film perforation device as described in any one of claims 1-7.

9. A ship for transporting liquefied gases, characterized in that, It includes a housing and a liquefied gas storage and transportation tank as described in claim 8 disposed within the housing.

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