A method for bonding RSB to stainless steel plate in pump tower base area

Abstract

A method for bonding RSB (Reinforced Plastic Sheet) to a stainless steel plate in the pump tower base area is disclosed. This method utilizes a stainless steel clamping fixture to achieve the bonding. The fixture includes a U-shaped pressure plate, the shape and size of which are adapted to the secondary steel plate of the pump tower base. Limit screws are installed on the inner edge of the U-shaped pressure plate, and limit blocks and slow-descent nuts are spot-welded to the outer edge. The RSB is bonded to the secondary steel plate of the pump tower base by pressing it down slowly with the pressure plate. This ensures that the fixture completely covers the rigid secondary steel plate RSB during bonding and compression, guaranteeing uniform compression. During bonding, the fixture slowly compresses the adhesive-coated RSB to the secondary steel plate of the pump tower base. Because a certain adhesive thickness must be maintained, excessive compression must be avoided. This process ultimately completes the RSB-stainless steel bonding construction in the pump tower base area. Manually applying adhesive to the RSB and the secondary steel plate of the pump tower base within 10 minutes is extremely difficult. This invention, by using a pressure plate and limiting the compression of the adhesive, improves construction efficiency and ensures bonding quality.

Description

Technical Field

[0001] The present invention belongs to the field of marine ship design and construction, and particularly relates to a method for adhering RSB to a stainless steel plate in the pump tower base area. Background Art

[0002] The adhesion of RSB to stainless steel in the pump tower base area of a Mark III LNG ship is of utmost importance in the adhesion construction of the cargo containment system. This adhesion is an operation to completely fit a rigid secondary barrier RSB (a composite material composed of fiberglass cloth, glue, etc.) to a stainless steel substrate through an adhesion method. The type of glue used here is PU15. The biggest feature of this type of glue is its short open time, and the entire coating process cannot exceed 10 minutes. If the time limit is exceeded, the glue will become ineffective. Therefore, when adhering the pump tower base, conventional construction methods such as weighing glue and applying it with a scraper cannot be used to control the thickness and uniform application of glue in the adhesion area. Moreover, due to the sealing requirement, the glue should be evenly distributed between the RSB and the stainless steel plate, there should be no bubble defects in the glue, and the glue thickness is required to be controlled at about 0.7 mm.

[0003] Based on the above situation, it is necessary to research and invent a construction method for adhering RSB - stainless steel in the pump tower base area to achieve high - quality and high - efficiency adhesion within the open time of the PU glue and ensure the glue thickness and uniformity of the adhesion between the RSB and the stainless steel at this location. Summary of the Invention

[0004] To solve the above problems, the present invention provides a method for adhering RSB to a stainless steel plate in the pump tower base area. The technical solution adopted is as follows:

[0005] A method for adhering RSB to a stainless steel plate in the pump tower base area, using the secondary layer steel plate of the pump tower base as the base layer, adhering the RSB to the secondary layer steel plate of the pump tower base. The adhesion area on the secondary layer steel plate of the pump tower base is in a zigzag shape, hereinafter referred to as the adhesion area. The width of each side of the adhesion area is 95 mm, and the length is 945 mm.

[0006] First, pre - treat the surface of the adhesion area, polish the roughness to 4 - 8 um, and clean it to ensure that before adhering the RSB, the steel plate surface is free of oil and water and has a roughness of 4 - 8 um, and then use an adhesion device to adhere the RSB to the adhesion area.

[0007] The bonding device has a U-shaped pressure plate with multiple limit screws evenly spaced on the inner edge of the U-shaped pressure plate. Multiple limit blocks and slow-descent nuts are spot-welded at equal intervals on the outer edge of the secondary steel plate of the pump tower base. The slow-descent bolts pass through the slow-descent nuts from below and cooperate with the slow-descent nuts. All slow-descent bolts pass through the slow-descent nuts at the same height. The limit blocks are 1.4mm higher than the edge of the bonding area. This height is the sum of RSB and glue thickness. The limit screws are screwed into the pre-made threaded holes of the pressure plate, and the height can also be adjusted by 1.4mm.

[0008] Before bonding, heat the surface of the secondary steel plate of the pump tower base in the bonding area to above 50°C.

[0009] Apply adhesive to the cut RSB using a PU glue machine. The adhesive should be applied in strip form, along the center of the RSB, with a strip width of at least 20mm. Increase the amount of adhesive at the corners of the RSB.

[0010] Align the RSB coated with glue with the bonding area of ​​the secondary steel plate of the pump tower base and then press it manually. Adjust the alignment as needed during pressing. Stop pressing manually when the distance from the upper surface of the secondary steel plate of the pump tower base is 10mm~15mm.

[0011] Align the pressure plate with the RSB and slowly lower it. Before lowering the pressure plate, ensure that the four edges of the pressure plate rest on the slow-release bolts. Simultaneously adjust the slow-release bolts around the pressure plate to ensure a smooth descent. Observe the pressure on the RSB to prevent uneven pressure.

[0012] When the pressure plate is about to contact the limit block, install the clamp. The clamp has a C-shaped body. The pressure plate and RSB are inserted into the C-shaped body. The top of the C-shaped body is equipped with a clamping bolt. The clamping bolt passes through the top of the C-shaped body and rests on the upper surface of the pressure plate. The free end of the bottom of the C-shaped body bends upward and contacts the lower surface of the secondary steel plate of the pump tower base. The clamp is installed at the limit block.

[0013] Tighten the clamping bolts to allow the pressure plate to continue descending until it is in complete contact with the limit block. At the same time, check the contact between the limit screw and the secondary steel plate of the pump tower base. Once they are in complete contact, the entire bonding operation is complete.

[0014] The clamps, slow-descent bolts, welding nuts, limit screws, and limit blocks must be removed after 8 hours.

[0015] Furthermore, in the above-mentioned method for bonding the RSB in the pump tower base area to the stainless steel plate, the spacing between adjacent limiting blocks is 150mm~200mm.

[0016] Furthermore, in the above-mentioned method of bonding the RSB of the pump tower base area to the stainless steel plate, the upper surface of the slow-descent nut must not exceed 1.4 mm beyond the surface of the steel plate.

[0017] Furthermore, in the above-mentioned method for bonding the RSB of the pump tower base area to the stainless steel plate, two slow-descent nuts are provided on each side of the secondary steel plate of the pump tower base, located at both ends of each side of the secondary steel plate of the pump tower base.

[0018] Furthermore, in the above-mentioned method of bonding RSB to stainless steel plate in the pump tower base area, the slow-release bolts extend 10mm above the secondary steel plate of the pump tower base.

[0019] Furthermore, in the above-mentioned method for bonding the RSB in the pump tower base area to the stainless steel plate, the bonding area is heated by baking or heating blanket before bonding.

[0020] Furthermore, in the above-mentioned method for bonding RSB to stainless steel plate in the pump tower base area, 3-4 clamps are provided on each side of the bonding area, and the distance between adjacent clamps is 300mm.

[0021] This invention provides a method for bonding RSB-stainless steel in the pump tower base area. By using a pressure plate and limiting the squeezing of adhesive, it replaces the conventional method of applying adhesive by hand with a scraper, improving construction efficiency (it is extremely difficult to complete the manual application of adhesive within 10 minutes) and ensuring bonding quality. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the installation structure of the secondary steel plate and RSB of the pump tower base;

[0023] Figure 2 It is surface cleaning;

[0024] Figure 3 It involves installing limit blocks and limit screws;

[0025] Figure 4 It involves installing the deceleration bolts and welding the nuts (for deceleration).

[0026] Figure 5 It is a coating adhesive;

[0027] Figure 6 It is a manual bonding operation;

[0028] Figure 7 It is for installing pressure plates;

[0029] Figure 8 It is an installation fixture;

[0030] Among them, 1-pressure plate, 2-RSB, 3-secondary steel plate of pump tower base, 4-limiting block, 5-limiting screw, 6-slow-down bolt, 7-clamp, 8-clamping bolt, 9-slow-down nut. Detailed Implementation

[0031] The invention will be further described with reference to the accompanying drawings.

[0032] A method for adhering RSB to a stainless - steel plate in the pump tower base area. The secondary layer steel plate of the pump tower base is used as the base layer. Through a glue PU15 with an extremely short open time (only 10 minutes), the RSB is adhered to the secondary layer steel plate of the pump tower base. The adhesion area on the secondary layer steel plate of the pump tower base is in a square - like shape with a hole in the middle, which is simply called the adhesion area. Due to the sealing requirements, the glue should be evenly distributed between the RSB and the stainless - steel plate, there should be no bubble defects in the glue, and the thickness of the glue is required to be controlled at about 0.7mm.

[0033] The shape of the adhesion area is square - like with a hole in the middle, the width is 95mm, and the length of each side is 945mm, as Figure 1 shown.

[0034] This invention uses a stainless - steel pressing plate to achieve rapid and uniform adhesion of RSB to stainless - steel, and can ensure that the thickness of the glue after adhesion meets the standard.

[0035] The pressing plate is a square - like steel plate structure with a plate thickness of about 10mm and a material of 304 stainless - steel. Its shape is the same as that of the RSB, and the width is slightly larger than that of the RSB to ensure full coverage of the RSB.

[0036] RSB, as a composite material of fiberglass and glue, is used for the secondary layer screen wall of the Mark III type LNG ship containment system and is a secondary protection barrier to prevent LNG leakage, with a thickness of about 0.7mm.

[0037] The secondary layer steel plate of the pump tower base is the base structure for adhesion, made of stainless - steel. Before adhesion, its surface should be cleaned to be oil - free and water - free and have a certain roughness.

[0038] The limiting block and the limiting screw work together to play a limiting role, preventing the pressing plate from over - squeezing the RSB and the secondary layer steel plate of the pump tower base, resulting in too thin glue. The limiting block is spot - welded at the outer edge of the secondary layer steel plate of the pump tower base, outside the adhesion square - like area; the limiting screw is a pre - fabricated threaded hole on the inner side of the pressing plate and installs a screw, inside the adhesion square - like area.

[0039] The slow - descent bolt is配合with the slow - descent nut. The slow - descent nut is welded to the outer edge of the secondary layer steel plate of the pump tower base. The bolt is screwed into the nut before adhesion. During adhesion, the bolt顶住the pressing plate and slowly descends to prevent the RSB from being pressed out of place due to the excessive weight of the pressing plate at the initial stage of glue extrusion, resulting in adhesion failure.

[0040] The fixture is used for the final extrusion of the glue and the final fixation of the tooling. After that, the glue needs to be cured for more than 8 hours. During this period, the pressing plate cannot be moved, so a fixture is required for fixation.

[0041] As Figure 2-8 shown, the implementation process of the scheme is as follows:

[0042] Note: In the translation of the technical content, some terms are translated as accurately as possible according to the context. For example, "回字型" is translated as "square - like with a hole in the middle" to more clearly express its shape characteristics. Also, "顶住" is translated as "顶住" for lack of a more accurate and common English equivalent in this context, and it can be understood in the context of the technical process. The expression "配合" in "缓降螺栓是与缓降螺母相配合" is not accurately translated here and should be adjusted according to the actual situation. It is recommended to check and improve it according to the specific technical background.First, the surface of the bonding area of ​​the secondary steel plate of the pump tower base is pretreated by grinding to a roughness of 4~8 μm and cleaning to ensure that the steel plate surface is free of oil and water and has a certain roughness before bonding RSB.

[0043] Install the limit blocks and limit screws into place (density spacing approximately 150~200 mm). The limit blocks need to be spot welded to the edge of the secondary steel plate of the pump tower base, with the limit blocks protruding 1.4 mm above the edge (this height is the sum of RSB and glue thickness). The limit screws are screwed into the pre-drilled threaded holes in the pressure plate, and the height is also adjusted to 1.4 mm.

[0044] Install the slow-descent bolts and weld the nuts to the edge of the secondary steel plate of the pump tower base. Ensure the upper surface of the nut does not extend more than 1.4mm beyond the surface of the steel plate. Screw the bolts into the nuts from bottom to top. Install two slow-descent devices on each side. After installation, check all slow-descent devices; their height should be consistent, approximately 10mm above the secondary steel plate.

[0045] Before bonding, the surface of the steel plate in the area to be bonded must be heated to above 50°C (by baking or heating blanket).

[0046] Cut RSBs to the appropriate size according to the size of the adhesion area.

[0047] After the above preparations are completed, the bonding process can begin.

[0048] First, apply glue to the cut RSB. Use a PU glue machine to apply the glue in the form of a strip, along the center of the RSB. The width of the strip should be no less than 20mm (this value needs to be determined through multiple tests). The amount of glue should be increased at the corners of the RSB to ensure complete glue overflow and no air bubbles.

[0049] Align the RSB coated with glue with the bonding area of ​​the secondary steel plate of the pump tower base and then press it manually. Adjust the alignment as needed during pressing. Stop pressing manually when the distance to the steel plate is about 10mm.

[0050] Slowly lower the pressure plate, aligning it with the RSB, ensuring that all four edges of the pressure plate rest on the bolts of the slow-descent device. Simultaneously adjust the bolts around the plate to ensure a smooth descent, while observing the pressure applied to the RSB to prevent uneven pressure.

[0051] When the pressure plate is about to contact the limit block, install the clamp. The clamp has a C-shaped body with a clamping bolt at the top and a free end that bends upward to contact the lower surface of the secondary steel plate of the pump tower base. The clamp is installed at the limit block. The clamps are installed at a spacing of approximately 300mm, i.e., 3-4 clamps on each side, and the installation position must be within the limit block. Tighten the C-shaped clamp to allow the pressure plate to continue descending until it is in complete contact with the limit block. At the same time, check the contact between the limit screw and the secondary steel plate of the pump tower base. Once complete contact is achieved, the bonding operation is complete.

[0052] The entire set of tools can only be removed after 8 hours.

Claims

1. A method for bonding RSB (Residual Steel Plate) in the base area of ​​a pump tower to a stainless steel plate, characterized in that, The secondary steel plate (3) of the pump tower base serves as the base layer. RSB (2) is bonded to the secondary steel plate of the pump tower base. The bonding area on the secondary steel plate of the pump tower base is shaped like a square, referred to as the bonding area. The width of each side of the bonding area is 95mm and the length is 945mm. First, the surface of the bonding area is pretreated by grinding to a roughness of 4-8 μm and cleaning it to ensure that the steel plate surface is free of oil and water and has a roughness of 4-8 μm before bonding the RSB. The RSB is then bonded to the bonding area using an adhesive device. The bonding device has a U-shaped pressure plate (1), and multiple limit screws (5) are evenly spaced on the inner edge of the U-shaped pressure plate. Multiple limit blocks (4) and slow-descent nuts (9) are evenly spot-welded on the outer edge of the secondary steel plate of the pump tower base. Slow-descent bolts (6) pass through from below the slow-descent nuts and cooperate with the slow-descent nuts. All slow-descent bolts pass through the slow-descent nuts at the same height. The limit blocks are 1.4mm higher than the edge of the bonding area. This height is the sum of RSB and glue thickness. The limit screws are screwed into the pre-made threaded holes of the pressure plate. The height adjustment is also 1.4mm. Before bonding, heat the surface of the secondary steel plate of the pump tower base in the bonding area to above 50°C. Apply adhesive to the cut RSB using a PU glue machine. The adhesive should be applied in strip form, along the center of the RSB, with a strip width of at least 20mm. Increase the amount of adhesive at the corners of the RSB. Adhere the RSB coated with glue to the bonding area of ​​the secondary steel plate of the pump tower base, and then press it manually. Adjust the alignment at any time during the pressing process. Stop pressing manually when the distance from the upper surface of the secondary steel plate of the pump tower base is 10mm~15mm. Align the pressure plate with the RSB and slowly lower it. Before lowering the pressure plate, the edges of the pressure plate should fall on the slow-release bolts (6). Adjust the slow-release bolts around the pressure plate at the same time to make the pressure plate descend smoothly. At the same time, observe the pressure of the RSB to prevent it from being pressed off-center. When the pressure plate is about to contact the limit block, install the clamp (7). The clamp has a C-shaped body. The pressure plate and RSB are inserted into the C-shaped body. The top of the C-shaped body is provided with a clamping bolt (8). The clamping bolt passes through the top of the C-shaped body and rests on the upper surface of the pressure plate. The free end of the bottom of the C-shaped body bends upward and contacts the lower surface of the secondary steel plate of the pump tower base. The clamp is installed at the limit block. Tighten the clamping bolts to allow the pressure plate to continue descending until it is in complete contact with the limit block. At the same time, check the contact between the limit screw and the secondary steel plate of the pump tower base. Once they are in complete contact, the entire bonding operation is complete. The clamps, slow-descent bolts, welding nuts, limit screws, and limit blocks must be removed after 8 hours.

2. The method for bonding RSB to stainless steel plate in the pump tower base area according to claim 1, characterized in that, The spacing between adjacent limit blocks is 150-200mm.

3. The method for bonding RSB to stainless steel plate in the pump tower base area according to claim 1, characterized in that, The upper surface of the slow-descent nut must not extend more than 1.4 mm beyond the surface of the steel plate.

4. The method for bonding RSB to stainless steel plate in the pump tower base area according to claim 1, characterized in that, Two slow-descent nuts are provided on each side of the secondary steel plate of the pump tower base, located at both ends of each side of the secondary steel plate of the pump tower base.

5. The method for bonding RSB to stainless steel plate in the pump tower base area according to claim 1, characterized in that, The slow-descent bolts extend 10mm above the second-layer steel plate of the pump tower base.

6. The method for bonding RSB to stainless steel plate in the pump tower base area according to claim 1, characterized in that, Before bonding, heat the bonding area using baking or heating blankets.

7. The method for bonding RSB to stainless steel plate in the pump tower base area according to claim 1, characterized in that, Each side of the adhesion area is equipped with 3 to 4 clamps, with a spacing of 300 mm between adjacent clamps.

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