An assembling method for a marine natural gas storage tank and a marine natural gas storage tank

Abstract

The present invention discloses an assembling method for a marine natural gas storage tank and a marine natural gas storage tank. In this assembling method for the marine natural gas storage tank, by marking angle lines on each cylinder section, when assembling the tank body, the angle lines can be used as a reference. After adjusting the positions of the cylinder sections so that the "0°" angles of the angle lines on the two cylinders to be spliced are directly opposite to each other, the two aligned cylinder sections are then welded and fixed, ensuring the installation accuracy of the tank body; by setting a first inspection line on the cylinder section where the gusset plate needs to be installed, when installing the gusset plate, controlling the tolerance of the distance D2 between the gusset plate and the first inspection line and the distance D1 between the first inspection line and the first position to be ±5 mm, ensuring the installation accuracy of the gusset plate on the cylinder section, preventing the laminated wood from being installed crookedly on the tank body due to poor installation accuracy of the gusset plate, and reducing the risk of mismatch between the position of the laminated wood and the card slot of the saddle.

Description

Technical Field

[0001] The present invention relates to the technical field of natural gas storage tanks, and in particular to a method for assembling a marine natural gas storage tank and a marine natural gas storage tank installed by using the method for assembling the marine natural gas storage tank. Background Art

[0002] The liquefied natural gas (LNG) storage tank on the hull is usually installed in the storage tank cabin of the hull. There are two saddle supports spaced apart on the bottom surface of the storage tank cabin. The liquefied natural gas storage tank includes a tank body, two enclosing plates and two laminated woods. The enclosing plates surround the outer circumference of the tank body along the axis line of the tank body. The two enclosing plates are spaced apart along the axial direction of the tank body. The laminated woods are fixed on the tank body through the enclosing plates. The tank body is in a horizontal state and is supported and fixed on the two saddle supports by the two laminated woods. In the prior art, there are the following deficiencies in the installation of the liquefied natural gas storage tank: the production of the tank body and the installation of the laminated woods are completed by different units respectively, and a unified standard cannot be formed, which easily causes the laminated woods to be installed obliquely, resulting in the non-matching of the positions of the laminated woods and the card slots of the saddle supports, and it is difficult to repair. Summary of the Invention

[0003] One object of the present invention is to provide a method for assembling a marine natural gas storage tank, which can improve the installation accuracy of the laminated wood and reduce the difficulty of repair.

[0004] Another object of the present invention is to provide a marine natural gas storage tank, which is convenient for assembly.

[0005] To achieve this purpose, the present invention adopts the following technical solutions:

[0006] On the one hand, a method for assembling a marine natural gas storage tank is provided. The marine natural gas storage tank includes a tank body, two enclosing plates and two laminated woods. The two enclosing plates are spaced apart along the axial direction of the tank body. Each laminated wood is fixed on the tank body through the enclosing plate. The tank body includes a plurality of cylinder sections spliced in sequence. The method for assembling the marine natural gas storage tank provides a plurality of the cylinder sections, two laminated woods and two groups of plate groups. Each group of plate groups includes three arc-shaped plates for assembling the enclosing plate. Angle scale lines are provided on the outer side surfaces of the respective cylinder sections, and the "0°" of the angle scale lines on two adjacent cylinder sections is facing each other. The method includes the following steps:

[0007] Step S10: Determine the two cylinder sections on which the enclosing plates need to be installed, and draw a first inspection line on the outer side surface of the cylinder section. The theoretical installation position of the enclosing plate on the cylinder section is the first position. Along the axis of the cylinder section, the distance between the first inspection line and the first position is D1;

[0008] Step S20, assembling the arc-shaped plates in each plate group on the cylinder section where the enclosure plate needs to be installed to form the enclosure plate, the distance between the enclosure plate and the first inspection line is D2, and the tolerance of D1 and D2 is controlled to be ±5 mm;

[0009] Step S30, dividing the cylinder segments into two groups, so that the cylinder segments in each group can be spliced in sequence to form a half tank body;

[0010] Step S40, assembling the cylinder sections in the same group in sequence to form the half tank body. During assembly, adjusting the positions of the cylinder sections to be assembled so that the "0°" of the angle marks on two adjacent cylinder sections are aligned, welding the joint ends of the two cylinder sections, and after the two groups of cylinder sections are assembled to obtain the two half tank bodies, closing the two half tank bodies and installing the two laminated woods on the two panels respectively to obtain the marine natural gas storage tank.

[0011] As an assembly method of the ship's natural gas storage tank and a preferred technical solution for the ship's natural gas storage tank, in the step S40, before closing the two half tank bodies, it is determined whether the plane where the end of the enclosure is located is perpendicular to the axis of the half tank body. If it is vertical, the laminated wood is installed on the enclosure, and then the two half tank bodies are closed. If it is not vertical, the enclosure is readjusted.

[0012] As a preferred technical solution of the assembling method and the ship-borne natural gas storage tank, in the step S40, the laminated wood is first fixed to the enclosure, and then the two half tank bodies are closed.

[0013] As an optimal technical solution for the assembly method and the shipboard natural gas storage tank, before the laminated wood is bonded to the enclosure, the installation position of the laminated wood is marked on the enclosure as a second position according to the design drawing of the shipboard natural gas storage tank, and when installing the laminated wood, the laminated wood is bonded to the second position.

[0014] As an optimal technical solution for the assembly method and the shipboard natural gas storage tank, a second inspection line is drawn on the enclosure, the distance between the second position and the second inspection line is D3, the distance between the laminated wood on the enclosure and the second inspection line is D4, and the difference W between D3 and D4 is compared. If W≥5mm, the position of the laminated wood is adjusted.

[0015] As a preferred technical solution of the assembling method and the marine natural gas storage tank, before step S10, the angle mark is drawn on the splicing end of the cylinder section according to the design drawing of the tank body.

[0016] As a preferred technical solution of the assembling method of the marine natural gas storage tank and the marine natural gas storage tank, in the step S40, when assembling each of the cylinder sections in the same group to form the semi-tank body in sequence, along the vertical direction, each of the cylinder sections is welded in sequence from bottom to top.

[0017] As a preferred technical solution of the assembling method of the marine natural gas storage tank and the marine natural gas storage tank, the closing of the two semi-tank bodies specifically includes the following steps:

[0018] Step S42: Place the two semi-tank bodies to be closed in a horizontal state on the same horizontal plane;

[0019] Step S43: Adjust the position of at least one of the semi-tank bodies so that the "0°" of the angle scale lines on the two semi-tank bodies to be closed are facing each other;

[0020] Step S44: Weld and fix the splicing ends of the two semi-tank bodies to be closed to obtain the tank body.

[0021] As a preferred technical solution of the assembling method of the marine natural gas storage tank and the marine natural gas storage tank, the step S43 specifically includes the following steps:

[0022] Step S431: Select at least two positioning areas between the splicing ends of the two semi-tank bodies, and all the positioning areas are distributed at intervals around the axis line of the semi-tank body;

[0023] Step S432: Weld all the positioning areas, after partially connecting the two semi-tank bodies to be closed, weld the areas outside the positioning areas between the splicing ends of the two semi-tank bodies.

[0024] On the other hand, a marine natural gas storage tank is also provided, which is assembled by using the above-mentioned assembling method of the marine natural gas storage tank.

[0025] The beneficial effects of the present invention are as follows: In the assembling method of the marine natural gas storage tank, in the assembling method of the marine natural gas storage tank, by marking angle scale lines on each cylinder section, when assembling the tank body, the angle scale lines can be used as a reference. After adjusting the positions of the cylinder sections so that the "0°" angles of the angle scale lines on the two cylinders to be spliced are facing each other, the two aligned cylinder sections are welded and fixed, ensuring the installation accuracy of the tank body; by setting the first inspection line on the cylinder section where the gusset plate needs to be installed, when installing the gusset plate, controlling the tolerance of the distance D2 between the gusset plate and the first inspection line and the distance D1 between the first inspection line and the first position to be ±5 mm, ensuring the installation accuracy of the gusset plate on the cylinder section, preventing the laminated wood from being installed obliquely on the tank body due to poor installation accuracy of the gusset plate, and reducing the risk of mismatch between the position of the laminated wood and the card slot of the saddle. Brief Description of the Drawings

[0026] The present invention will be further described in detail below with reference to the drawings and embodiments.

[0027] Figure 1 It is a schematic diagram showing that in the embodiment of the present invention, each of the cylinder sections in the same group is sequentially assembled to form the semi-tank body.

[0028] Figure 2 It is a structural diagram of the semi-tank body, the enclosing plate and the laminated wood in the embodiment of the present invention.

[0029] Figure 3 It is a structural diagram after the two semi-tank bodies in the embodiment of the present invention are closed.

[0030] In the figure:

[0031] 1. Cylinder section; 2. Angle graduation line; 3. Enclosing plate; 4. Plane where the end of the enclosing plate is located; 5. Axis line of the semi-tank body; 6. First inspection line; 7. Laminated wood. Detailed Embodiment

[0032] To make the technical problems solved by the present invention, the technical solutions adopted and the achieved technical effects clearer, the technical solutions of the embodiments of the present invention will be further described in detail below with reference to the drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present invention.

[0033] In the description of the present invention, unless otherwise clearly defined and limited, the terms "connected", "connected to" and "fixed" shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection or an integral body; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0034] In the present invention, unless otherwise clearly specified and defined, the first feature being "above" or "below" the second feature may include direct contact between the first and second features, or may include the first and second features not being in direct contact but being in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "beneath" and "underneath" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the horizontal height of the first feature is less than that of the second feature.

[0035] As Figure 1 and Figure 3 shown, the present invention provides an assembling method for a marine natural gas storage tank. Among them, the marine natural gas storage tank includes a tank body, two enclosing plates 3 and two laminated woods 7. The two enclosing plates 3 are spaced apart along the axial direction of the tank body. Each laminated wood 7 is fixed to the tank body through the enclosing plate 3. The tank body includes a plurality of cylinder sections 1 spliced in sequence. In this assembling method for the marine natural gas storage tank, a plurality of cylinder sections 1, two laminated woods 7 and two groups of plate sets are provided. Each group of plate sets includes three arc-shaped plates for assembling the enclosing plate 3. Specifically, since both ends of the tank body in the axial direction are sealed, among the provided cylinder sections 1, two of the cylinder sections 1 have a structure with one end open and the other end closed, and all the remaining cylinder sections 1 have a structure with both ends open. Angle scale lines 2 are provided at the splicing ends of each cylinder section 1. In this example, each angle scale line 2 is marked with "0°", "90°", "180°" and "270°". The "0°" of the angle scale lines 2 at the splicing ends of adjacent two cylinder sections 1 includes the following steps:

[0036] Step S10: Determine the two cylinder sections 1 where the enclosing plate 3 needs to be installed, and draw a first inspection line 6 on the outer side surface of the cylinder section 1. The theoretical installation position of the enclosing plate 3 on the cylinder section 1 is the first position. Along the axial direction of the cylinder section 1, the distance between the first inspection line 6 and the first position is D1;

[0037] Step S20: Assemble the arc-shaped plates in each group of plate sets on the cylinder section 1 where the enclosing plate 3 needs to be installed to form the enclosing plate 3. The distance between the enclosing plate 3 and the first inspection line 6 is D2. Control the tolerance of D1 and D2 to be ±5 mm, that is, control the difference between D1 and D1 to be less than or equal to 5 mm;

[0038] Step S30: Divide the cylinder sections 1 into two groups so that the cylinder sections 1 in each group can be spliced in sequence to form a semi-tank body;

[0039] Step S40: Assemble each cylinder section 1 in the same group in sequence to form a semi-tank body. During assembly, adjust the position of the cylinder section 1 to be assembled so that the "0°" of the angular scale lines 2 on two adjacent cylinder sections 1 are aligned. Weld the splicing ends of the two cylinder sections 1. After the two groups of cylinder sections 1 are assembled to obtain two semi-tank bodies, close the two semi-tank bodies and install two laminated woods 7 on the two enclosing plates 3 respectively to obtain a marine natural gas storage tank.

[0040] It can be understood that the inner sidewall of the cylinder section 1 has many structural bodies (such as stiffeners, etc.). After each cylinder section 1 is assembled to form a semi-tank body, the structural bodies near the splicing ends of two adjacent cylinder sections 1 will be spliced together to form a whole. In this way, after the tank body is assembled, the stiffeners inside each cylinder section 1 can jointly act to effectively strengthen the overall structure of the tank body. In the assembling method of this marine natural gas storage tank, by providing angular scale lines 2 on each cylinder section 1, when assembling the tank body, the angular scale lines 2 can be used as a reference. After adjusting the position of the cylinder section 1 so that the "0°" angles of the angular scale lines 2 on the two cylinders to be spliced are aligned with each other, then weld and fix the two aligned cylinder sections 1, ensuring the installation accuracy of the tank body; by providing a first inspection line 6 on the cylinder section 1 where the enclosing plate 3 needs to be installed, when installing the enclosing plate 3, control the tolerance of the distance D2 between the enclosing plate 3 and the first inspection line 6 and the distance D1 between the first inspection line 6 and the first position to be ±5 mm, ensuring the installation accuracy of the enclosing plate 3 on the cylinder section 1, preventing the laminated wood 7 from being installed crooked on the tank body due to poor installation accuracy of the enclosing plate 3, and reducing the risk of mismatch between the position of the laminated wood 7 and the card slot of the saddle. In the assembling method of this marine natural gas storage tank, even if the enclosing plate 3 is installed crooked, it can be detected in time, reducing the difficulty of repair.

[0041] In this example, the two first inspection lines 6 are located at the positions of FR57 + 400 and FR60 + 400. In other examples, the position of the first inspection line 6 can be flexibly adjusted, and the position of the first inspection line 6 is not specifically limited here.

[0042] Further, in step S40, before closing the two semi-tank bodies, judge whether the plane 4 where the end of the enclosing plate is located is perpendicular to the axis line 5 of the corresponding semi-tank body. If it is perpendicular, install the laminated wood 7 on the enclosing plate 3, and then close the two semi-tank bodies. If it is not perpendicular, readjust the enclosing plate 3. This step is mainly to check again whether the enclosing plate 3 is offset on the cylinder section 1. If the plane 4 where the end of the enclosing plate is located is not perpendicular to the axis line 5 of the corresponding semi-tank body, it indicates that the enclosing plate 3 is offset on the cylinder section 1, and it is necessary to repair the enclosing plate 3 or the semi-tank body and readjust the position of the enclosing plate 3 to avoid the laminated wood 7 being installed crooked due to the crooked installation of the enclosing plate 3.

[0043] In step S40, first fix the laminated wood 7 on the gusset plate 3, and then close the two half tanks. Since in the previous steps, the gusset plate 3 was reinspected, basically ensuring that the position accuracy of the gusset plate 3 meets the requirements. Therefore, after fixing the laminated wood 7 on the gusset plate 3, the two half tanks can be closed, and the process of fixing the laminated wood 3 on the gusset plate 3 is advanced, which is beneficial to shortening the assembly cycle of the marine natural gas storage tank. Of course, in other embodiments, the two half tanks can also be closed first, and then the laminated wood 7 can be fixed on the gusset plate 3.

[0044] Before bonding the upper laminated wood 7 to the gusset plate 3, first, according to the design drawing of the marine natural gas storage tank, mark the installation position of the laminated wood 7 on the gusset plate 3 as the second position. When installing the laminated wood 7, bond the laminated wood 7 at the second position to further reduce the risk of the laminated wood 7 being installed crooked.

[0045] To further check the installation accuracy of the laminated wood 7, draw a second inspection line on the gusset plate 3. The distance between the second position and the second inspection line is D3, and the distance between the laminated wood 7 on the gusset plate 3 and the second inspection line is D4. Compare the difference value W between D3 and D4. If W≥5mm, then adjust the position of the laminated wood 7. In this example, the second inspection line coincides with the first inspection line 6.

[0046] Specifically, before step S10, according to the design drawing of the marine natural gas storage tank, draw angle scale lines 2 on the outer side wall of the cylinder section 1 to ensure the accuracy of the angle scale lines 2.

[0047] In this embodiment, in step S40, when assembling the cylinder sections 1 in the same group to form a half tank in sequence, weld the cylinder sections 1 in sequence from bottom to top along the vertical direction to facilitate the assembly of the half tank.

[0048] Since the length of the tank body is generally 20m - 50m, it is difficult to close the half tanks in the vertical direction. In this embodiment, closing the two half tanks specifically includes the following steps:

[0049] Step S42: Place the two half tanks to be closed in a horizontal state on the same horizontal plane;

[0050] Step S43: Adjust the position of at least one of the half tanks so that the "0°" of the angle scale lines 2 on the two half tanks to be closed is facing each other;

[0051] Step S44: Weld and fix the splicing ends of the two half tanks to be closed to obtain the tank body.

[0052] To facilitate the positioning of the two half tanks to be closed and prevent the situation of being installed crooked due to the displacement of the half tanks during the welding and fixing process, step S43 specifically includes the following steps:

[0053] Step S431: Select at least two positioning areas between the splicing ends of the two semi-tanks. All the positioning areas are distributed at intervals around the axis line 5 of the semi-tank.

[0054] Step S432: Weld all the positioning areas. After the two semi-tanks to be joined are partially connected, weld the areas outside the positioning areas between the splicing ends of the two semi-tanks.

[0055] With this design, by welding at least two positioning areas, pre-positioning of the two semi-tanks can be achieved, facilitating subsequent welding construction.

[0056] The material of the gusset plate 3 is stainless steel, and the material of the laminated wood 7 is wood. In step S40, installing the laminated wood 7 on the gusset plate 3 specifically means: using an adhesive to bond and fix the laminated wood 7 on the gusset plate 3. The material of the gusset plate 3 is stainless steel to facilitate fixing the laminated wood 7 on the gusset plate 3.

[0057] In another embodiment, a marine natural gas storage tank is also provided, which is assembled by using any of the above-mentioned assembly methods for marine natural gas storage tanks. By engraving angle lines 2 on each cylinder section 1, when assembling the tank body, the angle lines 2 can be used as a reference. After adjusting the position of the cylinder section 1 so that the "0°" angles of the angle lines 2 on the two cylinders to be spliced are directly opposite to each other, then weld and fix the two aligned cylinder sections 1, ensuring the installation accuracy of the tank body; by setting a first inspection line 6 on the cylinder section 1 where the gusset plate 3 needs to be installed, when installing the gusset plate 3, control the tolerance of the distance D2 between the gusset plate 3 and the first inspection line 6 and the distance D1 between the first inspection line 6 and the first position to be ±5 mm, ensuring the installation accuracy of the gusset plate 3 on the cylinder section 1, preventing the laminated wood 3 from being installed crookedly on the tank body due to poor installation accuracy of the gusset plate 3, reducing the risk of mismatch between the position of the laminated wood 7 and the card slot of the saddle, and reducing the assembly difficulty.

[0058] In the description of this article, it should be understood that the orientation or positional relationships such as "upper", "lower", "left", "right", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, so it cannot be understood as a limitation to the present invention. In addition, the terms "first" and "second" are only used for distinction in description and do not have special meanings.

[0059] In the description of this specification, the description referring to terms such as "one embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example.

[0060] In addition, it should be understood that although this specification is described according to implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0061] The technical principle of the present invention is described above in conjunction with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the scope of protection of the present invention in any way. Based on the explanations herein, those skilled in the art can associate other specific implementations of the present invention without paying creative labor, and these methods will fall within the scope of protection of the present invention.

Claims

1. An assembling method for a marine natural gas storage tank, the marine natural gas storage tank comprising a tank body, two enclosing plates and two laminated woods, the two enclosing plates being spaced apart along the axial direction of the tank body, each laminated wood being fixed to the tank body through the enclosing plate, the tank body comprising a plurality of barrel sections sequentially spliced, characterized in that: The assembling method of the marine natural gas storage tank provides a plurality of the cylinder sections, two laminated woods, and two groups of plate sets. Each group of the plate sets includes three arc-shaped plates for assembling the surrounding plate. Angle scale lines are provided on the outer side surfaces of all the cylinder sections, and the "0°" of the angle scale lines on two adjacent cylinder sections are aligned. The method includes the following steps: Step S10: Determine two cylinder sections on which the surrounding plate needs to be installed, and draw a first inspection line on the outer side surface of the cylinder section. The theoretical installation position of the surrounding plate on the cylinder section is the first position. Along the axial direction of the cylinder section, the distance between the first inspection line and the first position is D1; Step S20: Assemble the arc-shaped plates in each group of plate sets on the cylinder section where the surrounding plate needs to be installed to form the surrounding plate. The distance between the surrounding plate and the first inspection line is D2. Control the tolerance of D1 and D2 to be ±5 mm; Step S30: Divide the cylinder sections into two groups so that the cylinder sections in each group can be sequentially spliced to form a semi-tank body; Step S40: Sequentially assemble the cylinder sections in the same group to form the semi-tank body. During assembly, adjust the position of the cylinder section to be assembled so that the "0°" of the angle scale lines on two adjacent cylinder sections are aligned. Weld the splicing ends of the two cylinder sections. After the two groups of cylinder sections are assembled to obtain two semi-tank bodies, close the two semi-tank bodies and install the two laminated woods on the two surrounding plates respectively to obtain the marine natural gas storage tank; In step S40, before closing the two semi-tank bodies, determine whether the plane where the end of the surrounding plate is located is perpendicular to the axis line of the corresponding semi-tank body. If it is perpendicular, install the laminated wood on the surrounding plate, and then close the two semi-tank bodies. If it is not perpendicular, readjust the surrounding plate.

2. The assembling method of the marine natural gas storage tank according to claim 1, wherein In step S40, first fix the laminated wood on the surrounding plate, and then close the two semi-tank bodies.

3. The assembling method of the marine natural gas storage tank according to claim 2, characterized in that, Before bonding the above-mentioned laminated wood to the surrounding plate, first, according to the design drawing of the marine natural gas storage tank, mark the installation position of the laminated wood on the surrounding plate as the second position. When installing the laminated wood, bond the laminated wood to the second position.

4. The assembling method of the marine natural gas storage tank according to claim 3, characterized in that, Draw a second inspection line on the surrounding plate. The distance between the second position and the second inspection line is D3, and the distance between the laminated wood on the surrounding plate and the second inspection line is D4. Compare the difference value W between D3 and D4. If W≥5 mm, adjust the position of the laminated wood.

5. The assembling method of the marine natural gas storage tank according to claim 1, characterized in that, Before step S10, according to the design drawing of the tank body, draw the angle scale lines at the splicing ends of the cylinder sections.

6. The assembling method of the marine natural gas storage tank according to claim 1, characterized in that, In step S40, when sequentially assembling the cylinder sections in the same group to form the semi-tank body, weld the cylinder sections sequentially from bottom to top along the vertical direction.

7. The assembling method of the marine natural gas storage tank according to claim 1, characterized in that, Closing the two semi-tank bodies specifically includes the following steps: Step S42: Place the two semi-tank bodies to be closed in a horizontal state on the same horizontal plane; Step S43: Adjust the position of at least one of the semi-tank bodies so that the "0°" of the angle scale lines on the two semi-tank bodies to be closed are aligned; Step S44: Weld and fix the splicing ends of the two semi-tanks to be joined together to obtain the tank.

8. The assembling method of the marine natural gas storage tank according to claim 7, characterized in that, The specific steps of step S43 are as follows: Step S431: Select at least two positioning areas between the splicing ends of the two semi-tanks. All the positioning areas are distributed at intervals around the axis line of the semi-tank. Step S432: Weld all the positioning areas. After the two semi-tanks to be joined together are partially connected, weld the areas outside the positioning areas between the splicing ends of the two semi-tanks.

9. A marine natural gas storage tank, characterized in that, It is assembled by using the assembly method of any one of the marine natural gas storage tanks according to claims 1 to 8.

Images