Manufacturing method of special-shaped single-leg plate in two-sided body of film cabin of LNG (Liquefied Natural Gas) ship

Abstract

The invention discloses a method for manufacturing a special-shaped single-leg plate in a two-sided body of a thin-film cabin of an LNG (liquefied natural gas) ship. The method comprises the following steps: manufacturing a semi-finished product of the special-shaped single-leg plate; spraying a fixed amount of glue on the two prefabricated second plywood and the semi-finished special-shaped single-leg plate; the two second plywood boards are placed on a designed enhanced foam board pressing mold; the special-shaped single-leg plate semi-finished product is placed on the two second plywood plates; the rigid secondary screen wall is placed on the top of the special-shaped single-leg plate semi-finished product, and a to-be-pressed blank is formed on the enhanced foam plate pressing mold; pressing the to-be-pressed blank by adopting a pressing machine to form a blank; and the blank is transferred to a numerical control machining center to be machined, redundant parts and glue are cut off, and a finished special-shaped single-leg plate is obtained. According to the special-shaped single-leg plate manufacturing method, the operation steps are simplified, the operation difficulty is reduced, the manufacturing efficiency of the special-shaped single-leg plate is improved, the size precision of the special-shaped single-leg plate can be improved, redundant glue can be removed, and the good manufacturing effect of the special-shaped single-leg plate is guaranteed.

Description

Technical Field

[0001] The invention belongs to the field of liquefied natural gas, relates to the structure of a membrane dihedron of an LNG ship, and specifically relates to a method for manufacturing a special-shaped single-leg plate in a membrane tank dihedron of an LNG ship. Background Art

[0002] LNG (liquefied natural gas) ships are special ships used for the transportation and storage of liquefied natural gas. They use LNG membrane type maintenance systems to achieve the storage of liquefied natural gas. The LNG membrane type maintenance system is a storage warehouse structure. The inner wall of the storage warehouse is assembled by splicing multiple membrane type insulation panels. The corner panels have a relatively complex structure due to their special structural environment. The corner panel structure is as follows: Figure 1 As shown, the dihedron in the corner area is mainly composed of three single-leg boards and a main layer of insulating parts, and the structure of the single-leg board is composed of a rigid secondary shielding material, a polyurethane foam board and a plywood. The three single-leg boards are two rectangular single-leg boards S and one special-shaped single-leg board C. The structure of the special-shaped single-leg board C is as shown in Figure 2 As shown, due to its unique special-shaped structure, it is currently impossible to complete one-time processing and forming. It must be assembled and processed multiple times to achieve this shape. The whole process is very complicated, which not only leads to a long time and low efficiency in the production of special-shaped single-leg plates, but also high requirements for operation during the production process, large errors, poor processing effects and other problems. It is difficult to guarantee the production effect and cannot meet the use requirements of the LNG membrane maintenance system.

[0003] The existing technology uses a flat press to press a plate with parallel upper and lower surfaces, but cannot press Figure 2 The shaped single leg board shown. Figure 3 As shown in the figure, the special-shaped single-leg board is made of rigid secondary screen material, polyurethane insulation material and plywood material. Due to the very strict shape requirements, it cannot be directly made into parts for bonding. If the glue is not cured under pressure, the surface will be uneven and the bonding strength will not meet the tensile requirements. If it is pressed and cured under pressure, glue will be squeezed out of all edges. Any extrusion will affect the shape of the special-shaped single-leg board and is not allowed, so it is difficult to meet the use requirements of the LNG membrane type maintenance system. Summary of the invention

[0004] Purpose of the invention: In order to overcome the deficiencies in the prior art, a method for manufacturing special-shaped single-leg plates in the dihedron of a membrane tank of an LNG ship is provided, which not only simplifies the operating steps and reduces the operating difficulty, thereby improving the manufacturing efficiency of the special-shaped single-leg plates, but also can improve the dimensional accuracy of the special-shaped single-leg plates, and can remove excess glue, thereby ensuring a good manufacturing effect of the special-shaped single-leg plates.

[0005] Technical solution: To achieve the above purpose, the present invention provides a method for manufacturing a special-shaped single leg plate in a dihedron of a membrane tank of an LNG ship, comprising the following steps:

[0006] S1: Making semi-finished products of special-shaped single-leg panels;

[0007] S2: Use glue spraying equipment to spray a fixed amount of glue per unit area on the two prefabricated second plywood panels and the semi-finished special-shaped single-leg panels;

[0008] S3: placing two second plywood sheets on the designed reinforced foam board pressing mold;

[0009] S4: placing the semi-finished special-shaped single-leg board on two second plywood boards;

[0010] S5: placing the rigid secondary screen wall on the top of the semi-finished product of the special-shaped single-leg board to form a blank to be pressed on the reinforced foam board pressing mold;

[0011] S6: using a press to press the blank to form a rough material;

[0012] S7: The raw material is transferred to the CNC machining center for processing, and the excess parts and glue are cut off to obtain the finished product of the special-shaped single-leg board.

[0013] Furthermore, the method for manufacturing the semi-finished product of the special-shaped single-leg board in step S1 is:

[0014] Placing the foam board on the upper part of the first plywood, pressing it with a flat press to form a blank large board, and cutting the blank large board to form at least two blanks;

[0015] Taking the first plywood as the reference plane, the semi-finished product of the special-shaped single-leg board is obtained by numerically controlling the cutting of the four sides of the blank.

[0016] Furthermore, in the numerical control cutting of step S1, a margin is left when cutting the two inclined surfaces connected to the two second plywood boards.

[0017] Furthermore, in the production of the semi-finished special-shaped single-leg board in step S1, the foam board is a composite board structure of a first foam board and a second foam board.

[0018] Furthermore, in the step S3, the enhanced foam board pressing mold is arranged on the press base, and the membrane surface of the enhanced foam board pressing mold matches the two inclined surfaces at the bottom of the special-shaped single-leg board semi-finished product.

[0019] Furthermore, in step S5, the length and width of the rigid secondary screen wall are larger than the dimensions of the top surface of the semi-finished special-shaped single-leg plate.

[0020] Furthermore, in step S5, the length and width of the rigid secondary screen wall are 30-50 mm larger than the dimensions of the top surface of the semi-finished special-shaped single-leg plate.

[0021] Furthermore, the processing steps in step S7 include cutting off the margins left on the two inclined surfaces, removing the glue hanging on the inclined surfaces, and cutting the bottom to the final size.

[0022] Beneficial effects: Compared with the prior art, the present invention adopts the method of pressing + digital cutting to produce the semi-finished product of the special-shaped single-leg board, and then uses a specially designed mold and press to complete the second pressing, which not only simplifies the operation steps and reduces the operation difficulty, but also solves the problem of low production efficiency caused by multiple assembly and multiple processing in the prior art, thereby improving the production efficiency of the special-shaped single-leg board, and this secondary pressing process method can well control the molding structure accuracy of the special-shaped single-leg board, and solves the problem of large production errors and low precision caused by multiple assembly and multiple processing in the prior art. In addition, this secondary pressing process can also effectively remove excess glue, solves the problem of glue extrusion in the prior art of multiple assembly and multiple processing, effectively improves the production accuracy of the special-shaped single-leg board, and ensures that the special-shaped single-leg board can meet the use requirements of the LNG membrane type maintenance system. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the structural diagram of the corner plate;

[0024] Figure 2 It is a structural diagram of the special-shaped single-leg plate C;

[0025] Figure 3 This is an exploded view of the special-shaped single-leg board;

[0026] Figure 4 It is a combined diagram of a foam board and a first plywood;

[0027] Figure 5 This is a schematic diagram of cutting the initial large plate;

[0028] Figure 6 A schematic diagram of CNC cutting of four sides of a blank;

[0029] Figure 7 A schematic diagram of the structure for pressing a blank to be pressed;

[0030] Figure 8 This is the structural diagram of the obtained special-shaped single-leg board. DETAILED DESCRIPTION

[0031] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0032] The present invention provides a method for manufacturing a special-shaped single leg plate in a dihedron of a membrane tank of an LNG ship, comprising the following steps:

[0033] S1: Production of semi-finished products of special-shaped single-leg panels, including:

[0034] like Figure 4 As shown, a foam board is placed on the first plywood 101, and the foam board is a composite board structure of a first foam board 102 and a second foam board 103. The cross section of a single leg board is close to 400*400mm, and the raw material thickness of the foam board must exceed 450. Such a thick foam board will have uneven top and bottom during foaming, resulting in the performance of the foam being lower than the lower limit.

[0035] The solution of the present invention is to make two layers of thickness to be bonded to the required thickness. The pressing thickness is solved by using the solution of 300+100, that is, the foaming can be foamed to a conventional thickness of 350mm, the upper and lower skins are removed, and the thickness of about 300mm is retained. Part of the 300mm thickness is layered into a thickness of 100mm, and the first foam board 102 and the second foam board 103 are combined into a combined board structure of 300+100 to bond and press, and at the same time, the first plywood 101 is placed at the bottom and pressed on a flat press.

[0036] like Figure 5 As shown, a flat press is used to press to form a pre-green sheet, and the pre-green sheet is cut to form two pre-green sheets;

[0037] like Figure 6 As shown, with the first plywood 101 as the reference plane, CNC cutting is performed on the four sides of the blank. A 3mm margin is left when cutting the two inclined surfaces connected to the two second plywood boards 2 during the CNC cutting. This is to avoid glue extrusion from the two inclined surfaces during the secondary pressing process. Two CNC processes are required to obtain a special-shaped single-leg board semi-finished product 1.

[0038] S2: Use glue spraying equipment to spray a fixed amount of glue per unit area on the two prefabricated second plywood panels 2 and the semi-finished special-shaped single-leg panel 1;

[0039] S3: Reference Figure 7 , placing two second plywoods 2 on the designed enhanced foam board pressing mold 4; wherein the enhanced foam board pressing mold 4 is arranged on a press base 6, and the upper part of the enhanced foam board pressing mold 4 is a press upper pressing head 5;

[0040] The membrane surface of the reinforced foam board pressing mold 4 matches the two inclined surfaces at the bottom of the special-shaped single-leg board semi-finished product 1.

[0041] S4: placing the semi-finished product 1 of the special-shaped single-leg board on the two second plywood boards 2;

[0042] S5: placing the rigid secondary screen wall 3 on the top of the semi-finished product 1 of the special-shaped single-leg board, wherein the length and width of the rigid secondary screen wall 3 are 30-50 mm larger than the size of the top surface of the semi-finished product 1 of the special-shaped single-leg board, so as to prevent the glue from being squeezed onto the upper surface of the rigid secondary screen wall 3, and forming a blank to be pressed on the reinforced foam board pressing mold;

[0043] S6: using the upper pressing head 5 of the press machine to press the blank to form a rough material, wherein the pressing pressure is fixed at 3-5 MPa, and this process is called secondary pressing;

[0044] S7: The raw material is transferred to the CNC machining center for processing. The processing steps include cutting off the margins left on the two bevels, cutting off the glue hanging on the bevels, and cutting the bottom to the final size. Finally, the Figure 8 The finished product of the special-shaped single-leg board is shown.

[0045] Through the above-mentioned production process and the obtained special-shaped single-leg board finished product, it can be known that the present invention adopts the method of pressing + digital cutting to produce the semi-finished special-shaped single-leg board, and then uses a specially designed mold and press to complete the second pressing, which not only simplifies the operation steps and reduces the operation difficulty, but also solves the problem of low production efficiency caused by multiple assembly and multiple processing in the prior art, thereby improving the production efficiency of the special-shaped single-leg board, and this secondary pressing process method can well control the molding structure accuracy of the special-shaped single-leg board, and solves the problem of large production errors and low precision caused by multiple assembly and multiple processing in the prior art. In addition, this secondary pressing process can also effectively remove excess glue, solves the problem of glue extrusion in the prior art of multiple assembly and multiple processing, effectively improves the production accuracy of the special-shaped single-leg board, and ensures that the special-shaped single-leg board can meet the use requirements of the LNG membrane type maintenance system.

Claims

1. A method for manufacturing a special-shaped single-leg plate in a dihedron of a membrane tank of an LNG ship, characterized in that: The steps include: S1: Making semi-finished products of special-shaped single-leg panels; S2: Use glue spraying equipment to spray a fixed amount of glue per unit area on the two prefabricated second plywood panels and the semi-finished special-shaped single-leg panels; S3: placing two second plywood sheets on the designed reinforced foam board pressing mold; S4: placing the semi-finished special-shaped single-leg board on two second plywood boards; S5: placing the rigid secondary screen wall on the top of the semi-finished product of the special-shaped single-leg board to form a blank to be pressed on the reinforced foam board pressing mold; S6: using a press to press the blank to form a rough material; S7: The raw material is transferred to the CNC machining center for processing, and the excess parts and glue are cut off to obtain the finished product of the special-shaped single-leg board.

2. The method for manufacturing a special-shaped single leg plate in a dihedron of a membrane tank of an LNG ship according to claim 1, characterized in that: The method for manufacturing the semi-finished special-shaped single-leg board in step S1 is as follows: Placing the foam board on the upper part of the first plywood, pressing it with a flat press to form a blank large board, and cutting the blank large board to form at least two blanks; Taking the first plywood as the reference plane, the semi-finished product of the special-shaped single-leg board is obtained by numerically controlling the cutting of the four sides of the blank.

3. The method for manufacturing a special-shaped single leg plate in a dihedron of a membrane tank of an LNG ship according to claim 2, characterized in that: In the numerical control cutting of step S1, a margin is left when cutting the two inclined surfaces connected to the two second plywood boards.

4. The method for manufacturing a special-shaped single leg plate in a dihedron of a membrane tank of an LNG ship according to claim 2, characterized in that: In the production of the semi-finished special-shaped single-leg board in step S1, the foam board is a composite board structure of a first foam board and a second foam board.

5. The method for manufacturing a special-shaped single leg plate in a dihedron of a membrane tank of an LNG ship according to claim 1, characterized in that: In step S3, the enhanced foam board pressing mold is arranged on the press base, and the membrane surface of the enhanced foam board pressing mold matches the two inclined surfaces at the bottom of the semi-finished special-shaped single-leg board.

6. The method for manufacturing a special-shaped single leg plate in a dihedron of a membrane tank of an LNG ship according to claim 1, characterized in that: In the step S5, the length and width of the rigid secondary screen wall are larger than the size of the top surface of the semi-finished special-shaped single-leg plate.

7. The method for manufacturing a special-shaped single leg plate in a dihedron of a membrane tank of an LNG ship according to claim 6, characterized in that: In the step S5, the length and width of the rigid secondary screen wall are 30-50 mm larger than the top surface of the semi-finished special-shaped single-leg board.

8. The method for manufacturing a special-shaped single leg plate in a dihedron of a membrane tank of an LNG ship according to claim 3, characterized in that: The processing steps in step S7 include cutting off the margins left on the two inclined surfaces, removing the glue hanging on the inclined surfaces, and cutting the bottom to the final size.

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