Strain monitoring device and liquefied natural gas storage equipment comprising same

Abstract

The utility model relates to a strain monitoring device and liquefied natural gas storage equipment comprising the same. The strain monitoring device comprises a strain monitoring sensor group, a sensor housing and a sensor housing fixing mechanism, the sensor housing comprises a housing first surface, a housing second surface, a housing third surface, a housing fourth surface and a housing fifth surface, the housing second surface, the housing third surface, the housing fourth surface and the housing fifth surface are connected with the housing first surface, and the housing first surface is detachably connected to the sensor housing; the strain monitoring sensor group is arranged in the sensor housing; the sensor housing also includes a sixth face, the sixth face of the sensor housing being disposed to have a central alignment point. In addition, the utility model further provides liquefied natural gas storage equipment comprising the strain monitoring device. The strain monitoring device provided by the utility model is convenient to install and arrange, and has the remarkable advantages of excellent low temperature resistance, no maintenance for a long time and the like.

Description

Technical Field

[0001] This invention relates to the field of fiber optic sensing and monitoring technology, and in particular to a strain monitoring device and a liquefied natural gas storage device including the same. Background Technology

[0002] Globally, liquefied natural gas (LNG) is highly favored as a clean energy source, with its share of energy supply continuing to rise and the industry showing strong growth momentum, becoming a new focus of the oil and gas industry. To diversify energy supply and optimize structure, countries are accelerating the construction of LNG receiving terminals, such as Japan, South Korea, the United States, and Europe. Meanwhile, international oil companies also see LNG as a new profit center, indicating it will become the next focus of global energy competition. However, technical challenges remain in the design, construction, operation, and maintenance of LNG terminals, such as foundation settlement, which poses a significant threat to the safe operation of storage tanks. Uneven settlement around the tank, in particular, can easily lead to structural damage or cracks, resulting in substantial economic losses. Due to its low temperature and high pressure characteristics, LNG is susceptible to environmental and media changes during transportation and storage, easily leading to stress and strain concentration and material fatigue, resulting in structural damage. Existing monitoring technologies are limited to surface and periodic inspections, unable to achieve real-time comprehensive monitoring and lacking early warning mechanisms, seriously affecting the safety and reliability of LNG storage tanks. Therefore, real-time monitoring of the stress and strain state of LNG tanks is of great significance for ensuring storage safety.

[0003] Therefore, existing technologies still need to be improved and enhanced.

[0004] It should be noted that the above introduction to the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of this application and facilitating understanding by those skilled in the art. It should not be assumed that these technical solutions are known to those skilled in the art simply because they have been described in the background section of this application. Utility Model Content

[0005] To address one or more of the aforementioned technical problems, this disclosure proposes a strain monitoring device and a liquefied natural gas (LNG) storage facility containing the same. This facilitates the convenient deployment of the strain monitoring device within the LNG storage facility and effectively monitors the strain and stress conditions within the LNG storage facility. Combined with the characteristics of fiber optic sensors, the deployed strain monitoring device can operate reliably for extended periods in extreme low-temperature environments, exhibiting significant advantages such as excellent low-temperature resistance and long-term maintenance-free operation.

[0006] In a first aspect of this disclosure, a strain monitoring device is provided, comprising: a strain monitoring sensor group, a sensor housing, and a sensor housing fixing mechanism, wherein the sensor housing is constructed as a hollow, cuboid structure, the sensor housing includes a first housing surface and a second, third, fourth, and fifth housing surface connected to the first housing surface, the second housing surface being positioned opposite the fourth housing surface, the third housing surface being positioned opposite the fifth housing surface, and the first housing surface being detachable. The sensor housing is connected to the aforementioned sensor housing; the outer surfaces of one or more of the second, third, fourth, and fifth surfaces of the aforementioned housing are provided with the aforementioned sensor housing fixing mechanism; the aforementioned strain monitoring sensor group is disposed inside the aforementioned sensor housing; the aforementioned sensor housing also includes a sixth surface, which is configured to have a center alignment point, such that the sixth surface, which is formed by the edges of the second, third, fourth, and fifth surfaces of the aforementioned housing, is centrally symmetrical with respect to the aforementioned center alignment point.

[0007] Furthermore, in some embodiments, the aforementioned monitoring sensor group is provided with a vertical strain monitoring sensor and a horizontal strain sensor, which are connected in series via an optical cable or optical fiber.

[0008] Furthermore, in some embodiments, the inner surface of each of the second, third, fourth, and fifth surfaces of the housing is provided with one or more cable-winding structures.

[0009] Furthermore, in some embodiments, a cable outlet port connecting the inside and outside of the sensor housing is provided on any one of the second, third, fourth, or fifth surfaces of the housing.

[0010] Furthermore, in some embodiments, the sixth side of the sensor housing is provided with a sixth housing side that is detachably connected to the sensor housing, and the sixth housing side is configured to face the first housing side.

[0011] Furthermore, in some embodiments, the aforementioned monitoring sensor group is configured to be detachably fixed to the inner surface of the sixth side of the aforementioned housing.

[0012] In a second aspect of this disclosure, a liquefied natural gas (LNG) storage device is also provided, comprising: the strain monitoring device described above; the vertical strain monitoring sensor is configured to have detection points arranged along the vertical direction of the LNG storage device; and the horizontal strain sensor is configured to have detection points arranged along the horizontal direction of the LNG storage device.

[0013] Furthermore, in some embodiments, the monitoring sensor group is configured to be fixed to the inner surface of the liquefied natural gas storage device; the sensor housing is configured to be fixed to the inner surface of the liquefied natural gas storage device by the sensor housing fixing mechanism, such that the monitoring sensor group is still inside the sensor housing; the sensor housing is configured to be sealed to the inner surface of the liquefied natural gas storage device.

[0014] Furthermore, in some embodiments, the optical cable led out from the strain monitoring device extends along the inner surface of the liquefied natural gas storage device to the perlite filling port of the liquefied natural gas storage device.

[0015] Furthermore, in some embodiments, the aforementioned liquefied natural gas storage device is provided with four perlite filling ports, which are evenly distributed at the top of the liquefied natural gas storage device near the sidewall; the sidewall of the liquefied natural gas storage device is configured with 12 vertically spaced monitoring layers, with four strain monitoring devices evenly distributed in each of the four monitoring layers near the bottom of the liquefied natural gas storage device; and four strain monitoring devices evenly distributed in every two of the eight monitoring layers near the top of the liquefied natural gas storage device.

[0016] Based on the above and the following embodiments, the beneficial effects of this disclosure are as follows:

[0017] 1) In some embodiments, the strain monitoring device of this disclosure is configured with a center alignment point on the sixth surface of the sensor housing, such that the sixth surface, which is composed of the edges of the second, third, fourth and fifth surfaces of the housing, is centrally symmetrical with respect to the center alignment point. The center alignment point facilitates the installation of the strain monitoring device on the inner wall of the liquefied natural gas storage device.

[0018] 2) Further, in some embodiments, a vertical strain monitoring sensor and a horizontal strain sensor are provided to monitor horizontal stress and strain as well as vertical stress and strain; further, in some embodiments, a sixth surface of the sensor housing is provided on the sixth surface of the housing, which is opposite to the first surface of the housing and is detachably connected to the sensor housing, and the monitoring sensor assembly is provided to be detachably fixed to the inner surface of the sixth surface of the housing, thereby facilitating transportation after leaving the factory and avoiding the loss or damage of parts of the complete monitoring sensor assembly.

[0019] 3) Further, in some embodiments, the sensor housing is fixed to the inner surface of the liquefied natural gas storage device by a sensor housing fixing mechanism, so that the monitoring sensor group is still inside the sensor housing; and the sensor housing is sealed to the inner surface of the liquefied natural gas storage device, thereby preventing perlite from seeping into the strain monitoring device during injection and affecting the measurement accuracy and lifespan of the internal sensors; and the sealing structure can prevent the injected perlite from seeping into the strain monitoring device later, which would cause the perlite layer inside the liquefied natural gas storage device to drop (i.e., decrease), thereby affecting the safety of the liquefied natural gas storage device when storing liquefied natural gas; furthermore, according to the stress condition of the liquefied natural gas storage device, more strain monitoring devices are set at the bottom and fewer strain monitoring devices are set at the top, and strain monitoring devices are evenly arranged in layers throughout the inner wall of the liquefied natural gas storage device, so as to better monitor the stress and strain of the liquefied natural gas storage device, thereby ensuring the safety of storing liquefied natural gas. Attached Figure Description

[0020] The above and other features, advantages and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description, wherein:

[0021] Figure 1 A diagram of a strain monitoring device according to an embodiment of the present disclosure is shown;

[0022] Figure 2 Another angle view of the strain monitoring device according to an embodiment of the present disclosure is shown;

[0023] Figure 3 A cross-sectional view of the strain monitoring device according to an embodiment of the present disclosure is shown from another angle;

[0024] Figure 4 A diagram illustrating a liquefied natural gas storage device according to an embodiment of the present disclosure is shown; and

[0025] In the various figures, the same or corresponding reference numerals indicate the same or corresponding parts, including: strain monitoring sensor group 10; vertical strain monitoring sensor 10-1; horizontal strain sensor 10-2; sensor housing 20; first surface of housing 20-1; second surface of housing 20-2; third surface of housing 20-3; fourth surface of housing 20-4; fifth surface of housing 20-5; sixth surface of housing 20-6; cable winding structure 21; cable outlet port 22; sensor housing fixing mechanism 30; optical fiber 40; strain monitoring device 100; first perlite filling port 200-1; second perlite filling port 200-2; third perlite filling port 200-3; fourth perlite filling port 200-4; liquefied natural gas storage equipment 1000. Detailed Implementation

[0026] Embodiments of this disclosure will now be described in more detail with reference to the accompanying drawings. While some embodiments of this disclosure are shown in the drawings, it should be understood that this disclosure can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this disclosure. It should be understood that the accompanying drawings and embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure.

[0027] In the description of embodiments of this disclosure, the term "comprising" and similar terms should be understood as open-ended inclusion, i.e., "including but not limited to". The term "based on" should be understood as "at least partially based on". The term "one embodiment" or "the embodiment" should be understood as "at least one embodiment". The terms "first", "second", etc., may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0028] It should be understood that for monitoring the deformation of the inner tank of an LNG storage tank, a feasible technical approach is to measure the change in distance between the inner and outer tanks to measure the deformation of the inner tank. For contact measurement, auxiliary supports need to be installed on both the inner and outer tanks, and then displacement sensors capable of operating at -170℃ (such as fiber optic displacement gauges) are fixed on both sides of the auxiliary supports to achieve displacement transfer measurement between the inner and outer tanks. This approach is not only difficult to install and debug, but it also damages the integrity of the inner tank's insulation felt and directly affects the perlite filling effect between the inner and outer tanks, easily forming "cold bridges" along the installation supports, affecting the overall cold insulation performance of the tank. For non-contact measurement, conventional optical methods are blocked by perlite; while electromagnetic and ultrasonic methods have several drawbacks: firstly, there are explosion-proof issues with the introduction of electronic components; secondly, electronic sensors cannot withstand the -170℃ low temperature and their service life does not meet the requirements for long-term monitoring; and thirdly, the nearly 1-meter-thick layer of perlite itself has a significant impact on the measurement accuracy.

[0029] To address this, this disclosure proposes a strain monitoring device comprising: a strain monitoring sensor array, a sensor housing, and a sensor housing fixing mechanism. This enables the deployed strain monitoring device to operate reliably for extended periods in extreme low-temperature environments, exhibiting significant advantages such as excellent low-temperature resistance and long-term maintenance-free operation.

[0030] The following section, together with the accompanying drawings, provides a detailed explanation.

[0031] Figure 1 A diagram of a strain monitoring device according to an embodiment of the present disclosure is shown; and Figure 2 Another angle view of a strain monitoring device according to an embodiment of the present disclosure is shown. Figure 1-2The image shows a strain monitoring device 100, which includes: a strain monitoring sensor group 10, a sensor housing 20, and a sensor housing fixing mechanism 30, wherein the sensor housing 20 is constructed as a hollow cuboid structure. Figure 1 (This is a top view of the first side). The sensor housing 20 includes a first housing surface 20-1 and a second housing surface 20-2, a third housing surface 20-3, a fourth housing surface 20-4, and a fifth housing surface 20-5 connected to the first housing surface 20-1, as shown below. Figure 2 As shown, it can be understood that the second surface 20-2 of the housing is positioned opposite the fourth surface 20-4 of the housing, and correspondingly, the third surface 20-3 of the housing is positioned opposite the fifth surface 20-4 of the housing. Since the first surface 20-1 of the housing is detachably connected to the sensor housing 20, it allows for… Figure 1 Only the four threaded holes left after the first surface 20-1 of the cover was removed, used to fix the first surface 20-1 of the cover, can be seen; in addition, two of the second surface 20-2, the third surface 20-3, the fourth surface 20-4, and the fifth surface 20-5 of the cover are also visible. Figure 1-2 The outer surfaces of the two (the upper and lower surfaces of the paper) are provided with sensor housing fixing mechanisms 30; the strain monitoring sensor group 10 is disposed inside the sensor housing 20; the sensor housing 20 also includes a sixth surface ( Figure 2 The sixth surface of the sensor housing 20 (the side closest to the mounting surface) is configured to have a center alignment point, such that the sixth surface, which is formed by the edges of the second surface 20-2, the third surface 20-3, the fourth surface 20-4, and the fifth surface 20-5 of the housing, is centrally symmetrical with respect to the center alignment point; and the center alignment point facilitates the installation of the strain monitoring device 100 as a whole (e.g., including the strain monitoring sensor group 10) on the inner wall (or outer wall) of the liquefied natural gas storage device.

[0032] Furthermore, in the illustrated embodiment, the monitoring sensor group 10 is provided with a vertical strain monitoring sensor 10-1 and a horizontal strain sensor 10-2, which are connected in series via an optical fiber 40. The vertical strain monitoring sensor 10-1 and the horizontal strain sensor 10-2 are used to monitor horizontal stress and strain as well as vertical stress and strain. At the same time, the series connection of the two facilitates the overall arrangement and avoids the need for internal wiring, which would result in clutter and be inconvenient for installation.

[0033] Furthermore, in the illustrated embodiment, the inner surface of each of the second surface 20-2, the third surface 20-3, the fourth surface 20-4, and the fifth surface 20-5 of the housing is provided with a cable winding structure 21. As shown in the figure, this facilitates the winding of optical fibers or cables inside the strain monitoring device 100 before they are led out, which is beneficial for maintenance. For example, if some of them fail, it is not necessary to rewire the entire system. Instead, the vertical strain monitoring sensor 10-1 and the horizontal strain sensor 10-2 can be rearranged using the redundant optical fibers inside the strain monitoring device 100.

[0034] Furthermore, in some embodiments, a cable outlet port 22 connecting the interior and exterior of the sensor housing 20 is provided on any one of the second surface 20-2, the third surface 20-3, the fourth surface 20-4, or the fifth surface 20-5 of the housing; the illustration shows only one of these surfaces. It should be understood that this cable outlet port 22 needs to allow the outgoing of optical fibers or cables while also ensuring a tight seal between the inside and outside of the strain monitoring device 100 to prevent perlite infiltration.

[0035] Furthermore, in some embodiments, the sixth surface of the sensor housing 20 is provided with a sixth surface 20-6 that is detachably connected to the sensor housing 20. Additionally, as shown in the figures, the sixth surface 20-6 is positioned opposite the first surface 20-1. Furthermore, in some embodiments, the monitoring sensor assembly 10 is detachably fixed to the inner surface of the sixth surface 20-6. This facilitates transportation after leaving the factory and avoids loss of parts or damage to the complete monitoring sensor assembly.

[0036] Furthermore, to further illustrate the relevant details of the strain monitoring device, the following description is provided in conjunction with the accompanying drawings.

[0037] Figure 3 A cross-sectional view of the strain monitoring device according to an embodiment of the present disclosure is shown from another angle. In this illustrated embodiment, the inner surface of each of the second, third, fourth, and fifth surfaces of the housing is provided with a (multiple) cable winding structure 21. This winding structure, as illustrated, can be a bent structure or a hook-shaped structure to facilitate the obtuse-angle bending of the optical fiber or cable inside the sensor housing 20. It should be understood that optical fibers or cables are different from metallic wires or cables; sharp angles or severe bending can easily damage the optical fiber itself. Furthermore, in the illustrated embodiment, a detachable connection method is shown for the sixth surface 20-6 of the housing, for example, by screw tightening. It should also be noted that the sixth surface 20-6 of the housing can be sealed to the sensor housing 20 to prevent perlite from seeping into the sensor housing 20 in final practical applications.

[0038] Furthermore, this disclosure also provides a liquefied natural gas storage device, which will be described in detail below with reference to the accompanying drawings.

[0039] Figure 4 A diagram of a liquefied natural gas (LNG) storage device according to an embodiment of the present disclosure is shown. In this illustrated embodiment, the LNG storage device 1000 includes the strain monitoring device 100 described above; wherein vertical strain monitoring sensors (too small to be specifically shown) are arranged with detection points along the vertical direction of the LNG storage device 1000; and horizontal strain sensors are arranged with detection points along the horizontal direction of the LNG storage device. This allows for more comprehensive monitoring of changes in horizontal or vertical strain stress in the LNG storage device 1000.

[0040] Furthermore, in some embodiments, the aforementioned monitoring sensor group is configured to be fixed to the inner surface (e.g., inner wall) of the liquefied natural gas storage device 1000; the sensor housing is configured to be fixed to the inner surface of the liquefied natural gas storage device by the sensor housing fixing mechanism, such that the monitoring sensor group remains inside the sensor housing; the sensor housing is configured to seal against the inner surface of the liquefied natural gas storage device. It should be understood that the sealing between the sensor housing and the inner surface of the liquefied natural gas storage device prevents perlite from seeping into the strain monitoring device during injection, thus preventing it from affecting the measurement accuracy and lifespan of the internal sensors; and the sealing structure prevents the injected perlite from seeping into the strain monitoring device later, thereby preventing a decrease in the perlite layer inside the liquefied natural gas storage device and affecting the safety of the liquefied natural gas storage device when storing liquefied natural gas.

[0041] Furthermore, in some embodiments, in order to utilize the overall layout of the liquefied natural gas storage device 1000, the optical cable leading from the strain monitoring device 100 is led along the inner surface of the liquefied natural gas storage device 1000 to the perlite filling ports 200-1, 200-2, 200-3, and 200-4 of the liquefied natural gas storage device 1000 (for example, the first perlite filling port 200-1, the second perlite filling port 200-2, the third perlite filling port 200-3, and the fourth perlite filling port 200-4; it should be understood that the perlite filling ports of the liquefied natural gas storage device 1000 are schematic, and those skilled in the art can understand from the illustration that perlite filling ports are opened on the liquefied natural gas storage device 1000 at the positions marked in the illustration).

[0042] Furthermore, in the illustrated embodiment, the aforementioned liquefied natural gas storage device is provided with four perlite filling ports 200-1, 200-2, 200-3, and 200-4, which are evenly arranged on the top of the liquefied natural gas storage device 1000 near the sidewall. The sidewall of the liquefied natural gas storage device 100 is configured with 12 vertically spaced monitoring layers. Four strain monitoring devices 100 are evenly arranged in each of the four monitoring layers near the bottom of the liquefied natural gas storage device 100, and four strain monitoring devices 100 are evenly arranged in every two of the eight monitoring layers near the top of the liquefied natural gas storage device 100. It should be understood that, based on the stress conditions of liquefied natural gas (LNG) storage equipment, more strain monitoring devices are installed near the bottom and fewer near the top. Furthermore, strain monitoring devices are evenly distributed in layers throughout the inner wall of the entire LNG storage equipment to better monitor stress and strain, thereby ensuring the safety of LNG storage.

[0043] It should also be understood that the purpose of LNG storage tank stress and strain monitoring is to select advanced sensing technology for the storage tank, design sensor deployment processes, and build a real-time stress and strain monitoring system for the inner tank. This provides data support for subsequent research on LNG storage tank failure mechanisms, reliability assessments of the storage tanks, optimization of receiving station operation management, and the realization of stable and efficient operation of the receiving station. Compared with other monitoring technologies, the solutions proposed in some embodiments of this disclosure have advantages such as being passive, radiation-free, unaffected by electromagnetic interference and lightning damage, unaffected by light source fluctuations and transmission line bending losses, inherently safe, and easy to network. These solutions meet the requirements for the number, location, and technical specifications of LNG storage tank inner tank stress and strain monitoring points, and can achieve remote signal transmission monitoring over 10km.

[0044] It should also be understood that in some other embodiments of this disclosure, the monitoring system composed of strain monitoring devices mainly consists of strain monitoring devices (e.g., fiber optic strain sensors), cryogenic transmission optical cables, ordinary transmission optical cables, a full-spectrum analyzer, a monitoring host, and monitoring software. Fiber optic monitoring devices are installed on the outer wall of the LNG storage tank. The measurement signals from the fiber optic strain sensors are transmitted to the full-spectrum analyzer host via transmission optical cables to process accurate strain data, and simultaneously the data is transmitted to the LNG storage tank health monitoring system.

[0045] It should also be understood that this disclosure is not intended to improve the strain monitoring sensor group 10, the vertical strain monitoring sensor 10-1, or the horizontal strain sensor 10-2 itself; those skilled in the art can select optical sensors that meet the requirements of the scene environment.

[0046] The various embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or technical improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

[0047] The above description is merely an optional embodiment of this disclosure and is not intended to limit this disclosure. Various modifications and variations can be made to this disclosure by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A strain monitoring device, comprising: The strain monitoring sensor assembly, sensor housing, and sensor housing fixing mechanism are characterized in that, The sensor housing is constructed as a hollow, cuboid structure. The sensor housing includes a first surface and a second, third, fourth, and fifth surface connected to the first surface. The second surface is positioned opposite the fourth surface, and the third surface is positioned opposite the fifth surface. The first surface is detachably connected to the sensor housing. A sensor housing fixing mechanism is provided on the outer surface of one or more of the second, third, fourth, and fifth surfaces. The strain monitoring sensor assembly is disposed inside the sensor housing. The sensor housing also includes a sixth surface, which is configured to have a center alignment point, such that the sixth surface, which is formed by the edges of the second, third, fourth, and fifth surfaces of the housing, is centrally symmetrical with respect to the center alignment point.

2. The strain monitoring device according to claim 1, characterized in that, The monitoring sensor group is equipped with a vertical strain monitoring sensor and a horizontal strain sensor, which are connected in series via an optical cable or optical fiber.

3. The strain monitoring device according to claim 2, characterized in that, The inner surface of each of the second, third, fourth, and fifth surfaces of the housing is provided with one or more cable winding structures.

4. The strain monitoring device according to claim 2, characterized in that, A cable outlet port connecting the inside and outside of the sensor housing is provided on any one of the second, third, fourth, or fifth surfaces of the housing.

5. The strain monitoring device according to claim 1, characterized in that, The sixth side of the sensor housing is provided with a sixth side of the housing that is detachably connected to the sensor housing, and the sixth side of the housing is configured to be opposite to the first side of the housing.

6. The strain monitoring device according to claim 5, characterized in that, The monitoring sensor assembly is configured to be detachably fixed to the inner surface of the sixth side of the housing.

7. A liquefied natural gas storage device, characterized in that, include: The strain monitoring device as described in any one of claims 2-4; The vertical strain monitoring sensor is configured to have detection points arranged along the vertical direction of the liquefied natural gas storage device; the horizontal strain sensor is configured to have detection points arranged along the horizontal direction of the liquefied natural gas storage device.

8. The liquefied natural gas storage device according to claim 7, characterized in that, The monitoring sensor array is configured to be fixed to the inner surface of the liquefied natural gas storage device; the sensor housing is configured to be fixed to the inner surface of the liquefied natural gas storage device by the sensor housing fixing mechanism, such that the monitoring sensor array remains inside the sensor housing; The sensor housing is configured to seal against the inner surface of the liquefied natural gas storage device.

9. The liquefied natural gas storage device according to claim 8, characterized in that, An optical cable led out from the strain monitoring device extends along the inner surface of the liquefied natural gas storage device to the perlite filling port of the liquefied natural gas storage device.

10. The liquefied natural gas storage device according to claim 9, characterized in that, The liquefied natural gas storage device is provided with four perlite filling ports, which are evenly distributed at the top of the liquefied natural gas storage device near the side wall. The sidewall of the liquefied natural gas storage device is configured with 12 vertically spaced monitoring layers, and each of the four monitoring layers near the bottom of the liquefied natural gas storage device is uniformly equipped with four strain monitoring devices. Four strain monitoring devices are evenly distributed in every two of the eight monitoring layers near the top of the liquefied natural gas storage device.

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