LNG (Liquefied Natural Gas) tank with vacuum regulation and control device

Abstract

The utility model discloses an LNG (Liquefied Natural Gas) tank with a vacuum regulation and control device, which comprises an LNG tank, the LNG tank is provided with an LNG liner and a heat insulation vacuum layer, the heat insulation vacuum layer wraps the LNG liner, and the heat insulation vacuum layer is provided with a vacuum pressure sensor; the adding mechanism is mounted on the LNG tank and used for adding a vacuum adsorbent to the heat insulation vacuum layer; the vacuum pressure sensor and the adding mechanism are electrically connected with the controller; when the vacuum pressure sensor monitors that the vacuum degree of the heat insulation vacuum layer is lower than a set lower limit vacuum degree value, the controller controls the adding mechanism to add the adsorbent to the heat insulation vacuum layer. The LNG gas tank has the advantages that vacuum adsorbents can be added into the heat insulation vacuum layer of the LNG gas tank so as to regulate and control the vacuum degree of the heat insulation vacuum layer, and the like.

Description

Technical Field

[0001] The utility model relates to vacuum control equipment, in particular to an LNG gas tank with a vacuum control device. Background Art

[0002] Inland LNG powered ships refer to ships that use liquefied natural gas (LNG) as their main fuel. Liquefied natural gas (LNG) is usually stored in LNG tanks.

[0003] The LNG gas tank is equipped with an insulating vacuum layer to insulate the LNG liner. As the gas tank is used for 3 to 5 years, a small amount of air will penetrate into the insulating vacuum layer, affecting the vacuum degree of the insulating vacuum layer, reducing the thermal insulation performance of the insulating vacuum layer, and easily causing the liquid LNG in the LNG liner to vaporize due to heat, causing the gas pressure of the LNG liner to increase, even exceeding the set threshold of the pressure relief valve. At this time, the LNG gas tank releases the LNG gas through the pressure relief valve to reduce the pressure. Therefore, in view of the defects of the prior art, it is necessary to develop a vacuum control device that can adjust the vacuum degree of the insulating vacuum layer of the LNG gas tank. Utility Model Content

[0004] The utility model aims to provide an LNG gas tank with a vacuum control device in view of the defects of the prior art.

[0005] In order to achieve the above-mentioned purpose of the utility model, the following technical solutions are adopted:

[0006] An LNG gas tank with a vacuum control device comprises an LNG gas tank, wherein the LNG gas tank is provided with an LNG liner and an insulating vacuum layer, wherein the insulating vacuum layer wraps the LNG liner, and the insulating vacuum layer is installed with a vacuum pressure sensor; an adding mechanism, wherein the adding mechanism is installed on the LNG gas tank and is used to add vacuum adsorbent to the insulating vacuum layer; and a controller, wherein the vacuum pressure sensor and the adding mechanism are both electrically connected to the controller; wherein, when the vacuum degree of the insulating vacuum layer monitored by the vacuum pressure sensor is lower than a set lower limit vacuum degree value, the controller controls the adding mechanism to add adsorbent to the insulating vacuum layer.

[0007] Further, the adding mechanism includes a casing, the casing is provided with a silo, and a discharge port is provided at the bottom of the silo; a baffle, the baffle is installed at the discharge port, and one end of the baffle is hingedly connected to the silo; a driving member, the driving member is provided with a piston rod and is installed on the casing; a swing rod, the swing rod is provided with a slide groove, one end of which is movably connected to the baffle, and the other end is hingedly connected to the casing; a feed pipe, one end of the feed pipe is connected to the thermal insulation vacuum layer, and the other end extends to the discharge port, and at least two feed valves are installed on the feed pipe at intervals; and a push rod, the push rod is installed on the piston rod, and the other end passes through the slide groove; wherein the driving member and the feed valve are electrically connected to the controller respectively.

[0008] Furthermore, the driving member is an electric push rod.

[0009] Furthermore, the baffle is connected to the silo via a hinge.

[0010] Furthermore, the utility model provides an LNG gas tank with a vacuum control device, which also includes a first support and a second support. The first support is installed on the baffle, one end of the swing rod is provided with a swing groove, one end of the fixed axis is installed on the first support, and the other end is provided with a swing groove; the second support is installed on the casing and is hingedly connected to the other end of the swing rod.

[0011] Furthermore, the feed pipe is installed obliquely relative to the LNG tank.

[0012] Furthermore, the utility model of an LNG gas tank with a vacuum control device also includes a vacuum pumping component, which is connected to the thermal insulation vacuum layer of the LNG gas tank and is used to extract the vacuum of the thermal insulation vacuum layer.

[0013] Furthermore, the vacuum pump includes a vacuum pump, a vacuum control valve, a vacuum pressure sensor and a vacuum pipe. The vacuum pump is connected to the insulating vacuum layer through the vacuum pipe. The vacuum control valve is installed on the vacuum pipe. The vacuum pressure sensor is installed on the LNG gas tank for monitoring the vacuum of the insulating vacuum layer. The vacuum pump, vacuum control valve and vacuum pressure sensor are all electrically connected to the controller.

[0014] Furthermore, the utility model provides an LNG gas tank with a vacuum control device, which also includes a temperature sensor and a heater. The temperature sensor is installed on the LNG gas tank to monitor the temperature of the insulating vacuum layer; the heater is installed on the insulating vacuum layer; the temperature sensor and the heater are both electrically connected to the controller.

[0015] Furthermore, the controller has a touch display screen.

[0016] The present invention has significant improvements over the prior art:

[0017] 1. The utility model has the function of real-time online monitoring of the vacuum degree of the vacuum layer of the LNG gas tank, and can add a vacuum adsorbent into the heat-insulating vacuum layer. The vacuum adsorbent can maintain long-term air adsorption efficiency, thereby solving the problem that the heat preservation effect of the gas tank is affected by the decrease in the vacuum degree of the heat-insulating vacuum layer of the gas tank.

[0018] 2. The present invention can also evacuate the thermal insulation vacuum layer, use a vacuum pressure sensor to monitor the vacuum degree of the thermal insulation vacuum layer, and then use a vacuum pumping component to evacuate the thermal insulation vacuum layer, so as to realize real-time monitoring of the vacuum degree of the thermal insulation vacuum layer of the LNG gas tank. When the vacuum degree is lower than the set lower limit vacuum degree value, the controller controls the vacuum pumping component to extract the vacuum of the thermal insulation vacuum layer, so that the thermal insulation vacuum layer maintains efficient thermal insulation performance, and avoids the liquid natural gas in the LNG liner from absorbing external heat and vaporizing, and the pressure of the LNG liner increases, causing the LNG gas tank to release. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation of the utility model or the technical solution in the prior art, the following is a brief introduction to the drawings required for the specific implementation or the prior art description. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to the actual scale.

[0020] Figure 1 This is a schematic diagram of the structure of an LNG gas tank with a vacuum control device according to the utility model;

[0021] Figure 2 A structural schematic diagram of the adding mechanism for opening the feed in the utility model;

[0022] Figure 3 for Figure 2 A schematic diagram of a structure in which the middle baffle is in an open state;

[0023] Figure 4 A structural schematic diagram of the closing of the adding mechanism in the utility model;

[0024] Figure 5 for Figure 4 A schematic diagram of the structure in which the middle baffle is in a closed state;

[0025] The serial numbers and corresponding component names in the figure are:

[0026] 1-LNG gas tank, 101-LNG liner, 102-insulating vacuum layer, 2-controller, 3-heater, 6-vacuum pipe, 7-vacuum control valve, 8-vacuum pump;

[0027] 9-adding mechanism, 91-housing, 92-bin, 93-first feed valve, 94-second feed valve, 95-feed pipe, 96-driving member, 97-piston rod, 98-baffle, 99-swing rod, 991-slideway, 910-push rod, 911-first support, 912-second support, 913-vacuum adsorbent, 914-swinging groove, 915-fixed axis;

[0028] 10- Temperature sensor, 11- Vacuum pressure sensor. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the technical solution in the present application, the technical solution of the present utility model will be clearly and completely described below in conjunction with the drawings and embodiments. Obviously, the described embodiments are only part of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present application.

[0030] Embodiment 1:

[0031] like Figure 1-5 As shown, an LNG gas tank with a vacuum control device in this embodiment includes an LNG gas tank 1, an adding mechanism 9 and a controller 2. The LNG gas tank 1 is provided with an LNG liner 101 and a heat-insulating vacuum layer 102, the heat-insulating vacuum layer 102 wraps the LNG liner 101, and the heat-insulating vacuum layer 102 is installed with a vacuum pressure sensor 11; the adding mechanism 9 is installed on the LNG gas tank 1, and is used to add a vacuum adsorbent to the heat-insulating vacuum layer 102; the vacuum pressure sensor 11 and the adding mechanism 9 are both electrically connected to the controller 2.

[0032] The controller 2 has a touch screen. The vacuum pressure sensor 11 monitors the vacuum data information of the heat insulating vacuum layer 102 and transmits it to the controller, which then displays the corresponding vacuum data information through the touch screen. The vacuum degree data information of the heat insulating vacuum layer can be quickly obtained by checking the touch screen.

[0033] The vacuum pressure sensor 11 monitors the vacuum in the heat-insulating vacuum layer 102 in real time, and the upper limit vacuum degree and the lower limit vacuum degree of the heat-insulating vacuum layer 102 can be preset on the controller.

[0034] It should be noted that the lower limit vacuum value and the upper limit vacuum value are pre-set on the controller to facilitate monitoring by the vacuum pressure sensor while keeping the vacuum of the thermal insulation vacuum layer within a better vacuum range, so that the thermal insulation vacuum layer can play a better role in thermal insulation.

[0035] It should be noted that the preset range of vacuum degree is 0.08Pa~0.0034Pa.

[0036] It is understandable that the lower limit vacuum value can be set to 0.08Pa, and the upper limit vacuum value can be set to 0.0034Pa.

[0037] Working method:

[0038] The vacuum pressure sensor 11 monitors the vacuum degree in the heat-insulating vacuum layer 102 in real time. When the vacuum degree of the heat-insulating vacuum layer 102 monitored by the vacuum pressure sensor 11 is lower than the set lower limit vacuum degree value, the controller 2 controls the adding mechanism 9 to add adsorbent to the heat-insulating vacuum layer 102. When the vacuum degree of the heat-insulating vacuum layer 102 monitored by the vacuum pressure sensor 11 reaches the set upper limit vacuum degree value, the controller 2 controls the adding mechanism 9 to stop adding adsorbent to the heat-insulating vacuum layer 102.

[0039] Embodiment 2:

[0040] Compared with embodiment 1, the difference is that a structure of adding mechanism is provided. Figure 1-5 As shown, the adding mechanism 9 includes a housing 91, a driving member 96, a baffle 98, a swing rod 99, a feed pipe 95 and a push rod 910. The housing 91 is provided with a silo 92, and a discharge port is provided at the bottom of the silo 92; the baffle 98 is installed at the discharge port, and one end of the baffle 98 is hingedly connected to the silo 92. The driving member 96 is provided with a piston rod 97 and is installed on the housing 91. The swing rod 99 is provided with a slide groove 991, one end of which is hingedly connected to the baffle 98, and the other end is hingedly connected to the housing 91. One end of the feed pipe 95 is connected to the heat-insulating vacuum layer 102, and the other end extends to the discharge port, and at least two feed valves are installed on the feed pipe 95 at intervals. The push rod 910 is installed on the piston rod 97, and the other end passes through the slide groove 991; wherein, the driving member 96 and the feed valve are electrically connected to the controller 2 respectively.

[0041] The silo 92 is used to hold the vacuum adsorbent 913. The vacuum adsorbent may include palladium monoxide, molecular sieve, activated carbon, etc. Two or three kinds of them may be mixed and used, such as palladium monoxide mixed with molecular sieve, molecular sieve and activated carbon, palladium monoxide mixed with activated carbon, palladium monoxide, molecular sieve and activated carbon. It should be noted that palladium monoxide, molecular sieve and activated carbon may all be granular structures. They may be conveniently guided to the feed pipe along the inclined baffle.

[0042] The driving member 96 can be an electric push rod structure. It is understandable that the driving member can drive the piston rod to extend and contract. The stroke of the piston rod extension and contraction can be set so that the piston rod drives the swing rod to swing.

[0043] It should be noted that if Figure 2As shown, the driving member 96 can drive the piston rod 97 to move telescopically. When the piston rod 97 is extended, the push rod 910 pushes the swing rod 99 to swing toward the feed pipe 95 and drives the baffle 98 to swing upward. When the piston rod is extended to the set extension stroke, it stops extending. At this time, the swing rod drives the baffle to close the discharge port at the bottom of the silo. When the piston rod is retracted, the push rod 910 drives the swing rod to swing away from the feed pipe 95 and drives the baffle 98 to swing downward. When the piston rod is retracted to the set retraction stroke, it stops retracting. At this time, the baffle is inclined to the discharge port of the silo, and the discharge port is in an open state. The vacuum adsorbent falls into the baffle from the discharge port, and the baffle guides the vacuum adsorbent to the feed pipe.

[0044] like Figure 1 , 2 As shown in FIG. 4 , the feed pipe 95 is installed at an angle relative to the LNG tank 1, so that the vacuum adsorbent entering the feed pipe can roll down easily.

[0045] It is understandable that the number of feed valves installed can be two.

[0046] like Figure 1-5 As shown, the feed valve includes a first feed valve 93 and a second feed valve 94. The first feed valve 93 and the second feed valve 94 are installed at intervals on the feed pipe 95. The first feed valve 93 and the second feed valve 94 are installed at intervals on the feed pipe 95. When feeding, the first feed valve 93 is opened first, so that the added vacuum adsorbent falls from the first feed valve 93 into the pipe section between the first feed valve 93 and the second feed valve 94, and then the first feed valve 93 is closed, thereby blocking the connection between the feed pipe and the silo. Then, the second feed valve 94 is opened, and the vacuum adsorbent enters the heat-insulating vacuum layer through the second feed valve.

[0047] One movable connection between the baffle and the silo is that the baffle 98 is connected to the silo 92 by a hinge. The baffle can swing relative to the silo by means of the hinge. Thus, the baffle can swing to close the discharge port at the bottom of the silo, thereby preventing the vacuum adsorbent in the silo from falling from the discharge port.

[0048] How adding an organization works:

[0049] In the initial state, the piston rod supports the swing rod, so that the swing rod supports the baffle plate to be buckled on the discharge port of the silo.

[0050] Adding vacuum adsorbent: Controller 2 controls driving member 96 to retract piston rod 97 and open first feed valve 93. Piston rod 97 drives push rod 910 to move away from feed pipe 95, drives swing rod 910 to swing away from feed pipe 95, and drives baffle 98 to swing downward relative to discharge port. At this time, baffle 98 is tilted downward relative to discharge port and discharge port is opened. Vacuum adsorbent 913 in silo 92 falls from discharge port to baffle 98, and baffle 98 guides vacuum adsorbent to feed pipe 95. When piston rod 97 retracts to the set retraction stroke, it stops retracting. Then, the controller 2 controls the first feed valve 93 to close, opens the second feed valve 94, and keeps it open for 3 to 5 seconds, the vacuum adsorbent in the feed pipe 95 falls into the heat-insulating vacuum layer 102, and then closes the second feed valve 94, opens the first feed valve 93, and keeps it open for 3 to 5 seconds, then closes the first feed valve 93, opens the second feed valve 94, and keeps it open for 3 to 5 seconds, and repeats the cycle in sequence until the vacuum pressure sensor monitors that the vacuum degree in the heat-insulating vacuum layer reaches the upper limit vacuum degree value, closes the first feed valve and the second feed valve, and the driving member drives the piston rod to extend, the piston rod 97 drives the swing rod 99 to swing close to the feed pipe 95 through the push rod 910, and drives the baffle 98 to swing upward, and when the piston rod extends to the set extension stroke, it stops extending, and at this time, the swing rod 99 drives the baffle 98 to close the discharge port at the bottom of the silo 92. That is, the addition of vacuum adsorbent to the heat-insulating vacuum layer is completed.

[0051] Embodiment 3:

[0052] Compared with the second embodiment, the difference is that: a connection structure of the swing rod is provided, and a first support 911 and a second support 912 are additionally installed. Figure 1-5 As shown, the first support 911 is installed on the baffle 98, a swing groove 914 is opened at one end of the swing rod 99, one end of the fixed axis 915 is installed on the first support 911, and the other end is penetrated by the swing groove 914; the second support 912 is installed on the housing 91 and is hingedly connected to the other end of the swing rod 99.

[0053] It should be noted that the swing rod 99 can be displaced relative to the first support 911 by means of the swing groove 914. The slide groove 991 allows the swing rod to be displaced relative to the piston rod. The swing groove 914 and the slide groove 991 can allow the swing rod to swing smoothly during the swinging process, thereby allowing the swing rod to drive the baffle to swing.

[0054] Embodiment 4:

[0055] Compared with any one of the embodiments 1-3, the difference is that: a vacuum pumping structure is additionally installed, and a vacuum pumping part is additionally installed. Figure 1As shown, the vacuum extractor is connected to the heat-insulating vacuum layer 102 of the LNG tank 1 and is used to extract the vacuum of the heat-insulating vacuum layer 102 .

[0056] In order to facilitate the control of the operation of the vacuum pumping member, the vacuum pumping member may be electrically connected to a controller, and the operation of the vacuum pumping member may be controlled by the controller.

[0057] The vacuum extractor is used to extract the vacuum in the thermal insulation vacuum layer 102, so that the thermal insulation vacuum layer 102 can maintain a good vacuum state, improve the thermal insulation effect of the thermal insulation vacuum layer 102, and effectively block the heat exchange between the LNG liner and the external atmosphere.

[0058] Embodiment 5:

[0059] Compared with Example 4, the difference is that a structure of a vacuum pump is provided. Figure 1 As shown, the vacuum pump includes a vacuum pump 8, a vacuum control valve 7, a vacuum pressure sensor 11 and a vacuum pipe 6. The vacuum pump 8 is connected to the insulating vacuum layer 102 through the vacuum pipe 6. The vacuum control valve 7 is installed on the vacuum pipe 6. The vacuum pressure sensor 11 is installed on the LNG tank 1 to monitor the vacuum of the insulating vacuum layer 102. The vacuum pump 8, the vacuum control valve 7 and the vacuum pressure sensor 11 are all electrically connected to the controller 2.

[0060] The vacuum control valve 7 can be an electric stop valve structure.

[0061] How to use the vacuum parts:

[0062] The vacuum pressure sensor 11 monitors the vacuum in the heat-insulating vacuum layer 102 in real time. When the monitored vacuum degree is lower than the lower limit vacuum degree, the controller 2 controls the vacuum pump 8 to work, and the vacuum pump 8 extracts the vacuum in the heat-insulating vacuum layer 102 through the vacuum pumping pipe 6. When the vacuum degree in the heat-insulating vacuum layer 102 reaches the upper limit vacuum degree, the controller controls the vacuum pump to stop working.

[0063] It is understandable that the vacuum pump can achieve the purpose of extracting the thermal insulation vacuum layer, thereby maintaining the vacuum degree of the thermal insulation vacuum layer within a set range, thereby providing good thermal insulation for the LNG liner 101 .

[0064] Embodiment 6:

[0065] Compared with any one of the embodiments 1-5, the difference is that in order to improve the efficiency of the extraction, a temperature sensor 10 and a heater 3 are additionally installed. Figure 1 As shown, the temperature sensor 10 is installed on the LNG tank 1 to monitor the temperature of the thermal insulation vacuum layer 102 ; the heater 3 is installed on the thermal insulation vacuum layer 102 ; the temperature sensor 10 and the heater 3 are both electrically connected to the controller 2 .

[0066] like Figure 1 As shown, the heater 3 includes a heating wire, which is installed in the heat-insulating vacuum layer.

[0067] Directions:

[0068] When the LNG tank 101 is empty, the controller 2 controls the heater 3 to work, and the heater 3 heats the insulating vacuum layer 102, so that the water and air in the insulating vacuum layer are heated. When the temperature sensor 10 monitors that the temperature of the insulating vacuum layer reaches the set temperature value (the set temperature value can be 220°C), the controller controls the heater to stop heating and starts the vacuum pumping component at the same time. At this time, the water in the insulating vacuum layer evaporates due to heat. The vacuum pumping component extracts the vacuum of the insulating vacuum layer, extracts the moisture in the insulating vacuum layer, reduces the moisture content in the insulating vacuum layer, and helps to improve the dryness of the insulating vacuum layer. When the vacuum degree monitored by the vacuum pressure sensor 11 reaches the upper limit vacuum degree setting value, the controller controls the vacuum pumping component to stop vacuuming.

[0069] It should be noted that the temperature of the thermal insulation vacuum layer is naturally cooled, which can further increase the vacuum degree of the thermal insulation vacuum layer.

[0070] It should be noted that when liquid LNG is still stored in the LNG liner, there is no need to use a heater to heat the insulating vacuum layer during vacuuming.

[0071] Application examples:

[0072] Guangxi Xijiang Heavy Industry Co., Ltd. is responsible for building two 5,000-ton LNG-powered bulk carriers for Guiping Zhonghai Transport Co., Ltd. The utility model is applied on the bulk carriers. Since their operation, the vacuum degree of the LNG gas tanks on board has been maintained at more than 95% of that at the time of leaving the factory.

[0073] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention of the utility model.

Claims

1. An LNG gas tank with a vacuum control device, characterized in that: include An LNG gas tank (1), the LNG gas tank (1) being provided with an LNG liner (101) and a heat-insulating vacuum layer (102), the heat-insulating vacuum layer (102) wrapping the LNG liner (101), and the heat-insulating vacuum layer (102) being provided with a vacuum pressure sensor (11); an adding mechanism (9), the adding mechanism (9) being installed on the LNG gas tank (1) and being used for adding a vacuum adsorbent to the heat insulating vacuum layer (102); and A controller (2), wherein the vacuum pressure sensor (11) and the adding mechanism (9) are both electrically connected to the controller (2); When the vacuum degree of the heat-insulating vacuum layer (102) monitored by the vacuum pressure sensor (11) is lower than a set lower limit vacuum degree value, the controller (2) controls the adding mechanism (9) to add an adsorbent to the heat-insulating vacuum layer (102).

2. The LNG gas tank with a vacuum control device according to claim 1, characterized in that: The adding mechanism (9) comprises A casing (91), wherein the casing (91) is provided with a silo (92), and a discharge port is provided at the bottom of the silo (92); a baffle (98), the baffle (98) being installed at the discharge port and having one end hingedly connected to the silo (92); A driving member (96), wherein the driving member (96) is provided with a piston rod (97) and is mounted on the housing (91); A swing rod (99), wherein the swing rod (99) is provided with a slide groove (991), one end of which is movably connected to the baffle (98), and the other end of which is hingedly connected to the housing (91); a feed pipe (95), one end of the feed pipe (95) being connected to the heat-insulating vacuum layer (102), the other end of the feed pipe (95) extending to the discharge port, and at least two feed valves being installed at intervals on the feed pipe (95); and A push rod (910), wherein the push rod (910) is mounted on the piston rod (97) and the other end of the push rod (910) passes through the slide groove (991); The driving member (96) and the feed valve are electrically connected to the controller (2) respectively.

3. The LNG gas tank with a vacuum control device according to claim 2, characterized in that: The driving member is an electric push rod.

4. The LNG gas tank with a vacuum control device according to claim 2, characterized in that: The baffle (98) is connected to the silo (92) via a hinge.

5. The LNG gas tank with a vacuum control device according to claim 2, characterized in that: It also comprises a first support (911), a fixed shaft (915) and a second support (912); the first support (911) is mounted on the baffle (98); one end of the swing rod (99) is provided with a swing groove (914); one end of the fixed shaft (915) is mounted on the first support (911) and the other end is provided with a swing groove (914); the second support (912) is mounted on the housing (91) and is hingedly connected to the other end of the swing rod (99).

6. The LNG gas tank with a vacuum control device according to claim 2, characterized in that: The feed pipe (95) is installed obliquely relative to the LNG tank (1).

7. The LNG gas tank with a vacuum control device according to claim 1, characterized in that: It also comprises a vacuum extracting component, which is connected to the heat-insulating vacuum layer (102) of the LNG gas tank (1) and is used to extract the vacuum of the heat-insulating vacuum layer (102).

8. The LNG gas tank with a vacuum control device according to claim 7, characterized in that: The vacuum pump comprises a vacuum pump (8), a vacuum control valve (7), a vacuum pressure sensor (11) and a vacuum pipe (6); the vacuum pump (8) is connected to the heat-insulating vacuum layer (102) via the vacuum pipe (6); the vacuum control valve (7) is installed on the vacuum pipe (6); the vacuum pressure sensor (11) is installed on the LNG tank (1) and is used to monitor the vacuum of the heat-insulating vacuum layer (102); the vacuum pump (8), the vacuum control valve (7) and the vacuum pressure sensor (11) are all electrically connected to the controller (2).

9. The LNG gas tank with a vacuum control device according to any one of claims 1 to 8, characterized in that: It also includes a temperature sensor (10) and a heater (3); the temperature sensor (10) is installed on the LNG gas tank (1) and is used to monitor the temperature of the thermal insulation vacuum layer (102); the heater (3) is installed on the thermal insulation vacuum layer (102); and the temperature sensor (10) and the heater (3) are both electrically connected to the controller (2).

10. The LNG gas tank with a vacuum control device according to claim 9, characterized in that: The controller (2) is provided with a touch display screen.

Images