Method for manually adhering secondary screen wall of cargo enclosure

Abstract

The invention discloses a manual adhesion method for a secondary screen wall of a cargo enclosure, which needs to use a stainless steel scraper with the blade width of 100mm to ensure that the scraper is clean, pollution-free and flat in edge. A constructor obtains a proper amount of glue according to the gluing area, a small amount of glue is taken on the scraper every time, and the glue is powerfully and evenly smeared on the RSB. Taking a proper amount of residual glue on a scraper for several times, continuously and uniformly smearing the glue on the RSB at one step, and controlling the thickness of the glue to be 0.2-1.2 mm. And the coiled FSB is stably laid on the area coated with the glue at a constant speed. In this way, the surface texture of the RSB is filled with the glue, and the glue is uniform, flat and free of bubbles so as to meet the construction requirement of the cargo containment system of the LNG transport ship.

Description

Technical Field

[0001] The invention belongs to the field of marine ship design and construction, and in particular relates to a method for manually bonding a secondary barrier wall of a cargo enclosure. Background Art

[0002] In the existing Mark III Flex LNG cargo containment system, after the secondary insulation is installed, the continuity of the secondary screen must be ensured. The secondary screen is mainly composed of a rigid secondary screen (RSB), which is prefabricated with glue between the primary and secondary insulation of each insulation board. The insulation boards are overlapped and bonded to the rigid secondary screen by a flexible secondary screen (FSB) to ensure the continuity of the secondary screen. In the manual bonding area (curved flexible secondary screen between corner insulation, flexible secondary screen with variable width between corner and plane areas, special-shaped flexible secondary screen in special areas (pump tower base, liquid dome and gas dome), and flexible secondary screen in trihedron area), the glue needs to be evenly applied to the rigid secondary screen when the flexible secondary screen is bonded to the prefabricated rigid secondary screen on the insulation board using PU glue.

[0003] The secondary screen wall plays a role in preventing leakage during the application of the cargo containment system. If the primary screen wall leaks, the secondary screen wall will directly contact the liquid LNG at -163℃ and ensure no leakage. In addition, because manual bonding is mostly used in corner areas, transition areas and other places that bear large deformation in actual operation, the manual bonding process is one of the key processes of the LNG cargo containment system. Therefore, the reliability of manual bonding of the secondary screen wall is the core capability of the LNG cargo containment system construction.

[0004] However, in actual operation, due to individual differences among construction workers during the construction process, the glue is often not fully applied to the gap, resulting in insufficient adhesion, uneven glue distribution, and the presence of bubbles, which ultimately leads to adhesion and debonding failure. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a method for manually bonding the secondary screen wall of the cargo enclosure, and the technical solution adopted is: A method for manually gluing a secondary wall of a cargo enclosure. Before the manual gluing construction begins, the size of the gluing area is measured, and the gluing area is calculated based on the data. The area of ​​the overflowing glue area needs to be added, and the gap between the insulating boards needs to be subtracted. The required amount of glue is calculated based on the gluing area.

[0006] Put the glue on a glue tray covered with plastic cloth. When taking glue from the glue machine, the glue outlet should be about 5mm away from the surface of the glue tray. As the amount of glue increases, the glue outlet should always be about 5mm away from the top layer of glue to reduce the contact between glue and air and avoid the formation of bubbles.

[0007] Prepare a clean and uncontaminated stainless steel scraper, and grind the sharp corners on both sides of the stainless steel scraper to make them smooth, with a chamfer size of 2mm.

[0008] After the glue and the stainless steel scraper are prepared, use the edge of the stainless steel scraper to obtain about 15g of glue from the bottom of the glue in the glue tray and along the edge of the glue, and quickly pull up the stainless steel scraper horizontally, and quickly and slightly swing the scraper horizontally left and right to completely separate the glue on the scraper from the glue on the glue tray, and the glue remains on the stainless steel scraper.

[0009] Press the glue on the stainless steel scraper to the starting point marked on the RSB in the adhesion area, tilt the scraper at a 45° angle so that the scraper is close to the RSB, and push the glue from one end to the other to ensure that the glue covers the RSB evenly and thinly until the color of the glue fades to colorless. Start the next glue removal and repeat the above operation until the adhesion area is evenly covered with a layer of light blue glue.

[0010] Divide the adhesion area into multiple areas with a length of 400mm-500mm. Evenly distribute the remaining glue according to the number of areas and apply the glue evenly to the RSB. Keep the stainless steel scraper at least 0.2mm away from the RSB surface. Then, visually check whether the RSB covered with glue has uneven color. Apply the remaining glue to a small area and be careful to avoid leaving knife marks when retracting the knife. Swing your wrist quickly left and right to keep the remaining glue on the blade in the place where glue is missing, especially in the overlapping area.

[0011] Finally, use a scraper to smooth the glue on the entire glue coating area, and control the scraper height between 0.6-0.8mm, with no bubbles or dents on the surface.

[0012] Take the prepared FSB roll and carefully unfold it, making sure that the FSB is aligned with the top of the glue coating area, except for the glue overflow area. Use one hand to gently hold the end of the FSB, and use the other hand to push the rolled FSB to unfold. During the unfolding process, pay attention to the upper and lower distances from the edge of the glue coating area, and ensure that the upper and lower distances are between 5mm-10mm.

[0013] Use a roller brush to gently roll around the corners of the FSB to ensure that the FSB fits tightly against the RSB.

[0014] The stainless steel scraper used in the present invention is more conducive to avoiding knife marks during the glue coating process, thereby reducing the requirements for construction workers to use the scraper and reducing the glue being too thin at both ends of the scraper due to excessive force, thereby reducing uneven glue coating.

[0015] By controlling the scraper height and determining the amount of glue applied each time, the first glue application ensures that the glue is evenly distributed in the texture of the RSB material, ensuring the bonding between the glue and the RSB material. The second glue application ensures that the glue is basically evenly distributed in the glue application area by controlling the scraper height and amount. The third time focuses on flattening a large area and insufficient glue in a small area. Compared with the original solution, this solution reduces the lack of glue in a large area caused by human error in estimating glue distribution, and the inability to fully press the glue into the texture of the RSB due to excessive glue taken at one time. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of a stainless steel scraper; Figure 2 This is a schematic diagram of a stainless steel scraper taking glue from the glue tray; Figure 3 This is a schematic diagram of the initial application of glue by a stainless steel scraper; Figure 4 This is a schematic diagram of a stainless steel scraper after applying glue repeatedly; Among them, 1-stainless steel scraper, 2-glue tray, 3-glue, 4-RSB. DETAILED DESCRIPTION

[0017] The present invention will be further described in conjunction with the accompanying drawings.

[0018] A method for manually gluing the secondary wall of the cargo enclosure. Before the manual gluing construction begins, the size of the gluing area is measured, and the gluing area is calculated based on this data (the area of ​​the overflowing glue area needs to be added and the gap between the insulation boards is subtracted). The required amount of glue is calculated based on the gluing area. The glue is placed on a glue tray covered with plastic cloth. When the glue is taken from the glue machine, the glue outlet is about 5 mm away from the surface of the glue tray. As the amount of glue increases, the glue outlet is always about 5 mm away from the top layer of glue, reducing the contact between the glue and the air and avoiding the generation of bubbles.

[0019] like Figure 1 As shown, prepare a clean and uncontaminated stainless steel scraper, and grind the sharp corners on both sides of the stainless steel scraper to make them smooth, with a chamfer size of about 2mm, to reduce the lack of glue on both ends of the scraper due to improper force distribution when applying glue. At the same time, avoid the scraper ends being too sharp to damage RSB.

[0020] After the glue and stainless steel scraper are ready, Figure 2 As shown, use the edge of the scraper to gently insert the bottom of the glue on the glue tray and take about 15g of glue along the edge of the glue, then quickly pull up the scraper horizontally and quickly and slightly swing the scraper horizontally left and right to completely separate the glue on the scraper from the glue on the glue tray, and the glue stays on the stainless steel scraper. Figure 3As shown, quickly and accurately press the glue on the stainless steel scraper to the starting point marked on the RSB in the adhesion area, tilt the scraper at a 45° angle, make the scraper close to the RSB, push the glue from one end to the other, and ensure that the glue covers the RSB evenly and thinly until the color of the glue fades to colorless. Start the next glue removal and repeat the above operation until the adhesion area is evenly covered with a layer of light blue glue, as shown in the figure. Figure 4 As shown. Divide the adhesion area into 400mm-500mm long areas, evenly distribute the remaining glue according to the number of areas, and evenly apply the glue to the RSB. The scraper should be at least 0.2mm away from the RSB surface. Then, visually check whether there are any uneven colors on the RSB covered with glue, apply the remaining glue to a small area, and be careful to avoid leaving knife marks when retracting the knife. Move your wrist quickly left and right to keep the remaining glue on the blade in the position where glue is missing (especially the overlap area). Finally, use a scraper to smooth the glue on the entire glue-coated area, and control the scraper height between 0.6-0.8mm. There should be no bubbles or depressions on the surface.

[0021] Take the prepared FSB roll, carefully unfold the FSB, make sure the FSB is aligned with the top of the glue coating area (except the overflow area), gently fix the unfolded FSB with one hand, and gently push the rolled FSB with the other hand to unfold it. Remember not to press the FSB roll. During the unfolding process, pay attention to the upper and lower distances from the edge of the glue coating area, and make sure the upper and lower distances are between 5mm-10mm to avoid the FSB being uncovered due to the wrong laying position, which will cause air to enter the glue and form bubbles. Use a roller brush to gently roll around the corners of the FSB to ensure that the FSB fits tightly with the RSB.

Claims

1. A method for manually bonding secondary screen walls of cargo enclosures, characterized in that: Before starting manual bonding, measure the size of the bonding area and use this data as the basis to calculate the glue coating area. You need to add the area of ​​the overflow area and subtract the gap between the insulation boards. Calculate the amount of glue required based on the glue coating area. Put the glue on a glue tray covered with plastic cloth. When taking glue from the glue machine, the glue outlet should be about 5mm away from the surface of the glue tray. As the amount of glue increases, the glue outlet should always be about 5mm away from the top layer of glue to reduce the contact between glue and air and avoid the generation of bubbles. Prepare a clean and uncontaminated stainless steel scraper, and grind the sharp corners on both sides of the stainless steel scraper to make them smooth, with a chamfer size of 2mm; After the glue and the stainless steel scraper are ready, use the edge of the stainless steel scraper to get about 15g of glue from the bottom of the glue in the glue tray and along the edge of the glue, and quickly pull up the stainless steel scraper horizontally, and quickly and slightly swing the scraper horizontally left and right to completely separate the glue on the scraper from the glue on the glue tray, and the glue stays on the stainless steel scraper; Press the glue on the stainless steel scraper to the starting point marked on the RSB in the adhesion area, tilt the scraper at a 45° angle, make the scraper close to the RSB, push the glue from one end to the other, and ensure that the glue covers the RSB evenly and thinly until the color of the glue fades to colorless, start the next glue removal and repeat the above operation until the adhesion area is evenly covered with a layer of light blue glue; Divide the adhesion area into multiple areas with a length of 400mm-500mm. Evenly distribute the remaining glue according to the number of areas and evenly apply the glue to the RSB. Keep the stainless steel scraper at least 0.2mm away from the RSB surface. Then, visually check whether there are any uneven colors on the RSB covered with glue. Apply the remaining glue to a small area and be careful not to leave knife marks when closing the knife. Move your wrist quickly left and right to keep the remaining glue on the blade in the place where glue is missing, especially in the overlapping area. Finally, use a scraper to smooth the glue on the entire glue coating area, and control the scraper height between 0.6-0.8mm, with no bubbles or depressions on the surface; Take the prepared FSB roll and carefully unfold it, making sure that the FSB is aligned with the top of the glue coating area. Except for the glue overflow area, use one hand to gently fix the end of the FSB, and use the other hand to push the FSB roll to unfold. During the unfolding process, pay attention to the distance from the edge of the glue coating area to ensure that the distance is between 5mm and 10mm. Use a roller brush to gently roll around the corners of the FSB to ensure that the FSB fits tightly against the RSB.

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