Aluminum Hull Ribs For A Wide Range Of Applications

- May 20, 2019-

Cold-formed steel has better cross-sectional performance per unit weight than hot-rolled steel products, and has a high surface finish and dimensional accuracy. Therefore, cold-formed steel can achieve the double effect of saving steel and saving energy by replacing hot-rolled steel. The use of a rib cold bending machine for processing hull profile members has the advantages of fast forming and high quality, which can shorten the product manufacturing cycle and improve production efficiency. With the rapid development of the shipbuilding industry and the increasing scale of ships, people's understanding of the application of high-strength steel has gradually increased, and high-strength steel has been widely used in aluminum hull rib structure. In the cold processing of steel, research on plastic processing, metal pressure processing, and sheet metal stamping processing has been in-depth, but few for ships and marine structures.

Aluminum alloy materials are widely used in aluminum hull ribs, mainly because of their small specific gravity and strong corrosion resistance, which can speed up the ship's speed when the ship is sailing. And because of its low density, it can effectively reduce the weight of the ship and ensure the stability of the ship. For the shipbuilding industry, it is a material with high utilization value. In the process of building aluminum alloy hulls, it is necessary to pay attention to the welding of aluminum alloy hulls, which is currently the biggest obstacle to the construction of aluminum alloy hulls. Compared with steel materials, aluminum alloy materials have much higher thermal conductivity than steel materials, and thermal expansion is 2.5 times that of steel materials, but the elastic modulus is only 1/3 of steel materials. These material properties make the aluminum alloy material more prone to large material deformation during welding than steel materials. This paper analyzes the welding deformation of aluminum alloy by the characteristics of deformation of aluminum alloy hull during welding, and studies the welding deformation control measures of aluminum alloy, which accumulates experience for mass production of aluminum alloy ships.

When assembling aluminum hull ribs, the assembly accuracy should be higher than that of ordinary steel ships. When assembling the slabs, the staggering degree of the slats should be within the standard range of 0.5mm, and the slat gap should be within the standard range of 1mm; The frame spacing, positional deviation, butt gap, and end point offset should be kept within the accuracy standard range of 1 mm; when assembling the bulkhead, the accuracy of the positional deviation is 2 mm, and the accuracy of the gap with the outer plate is 1 mm.

When assembling, pay attention to the order of assembly. It is best to start assembling from the middle, and then gradually start assembly on the raft and the sides. If the aluminum alloy hull is constructed in sections, then the bow and center keel should be found first, then the rib sections on both sides should be pressed, and finally assembled in these two directions. This assembly method is mainly Based on the ship's raft, although it is difficult to implement, it produces small errors and high precision.