Application of aluminum alloy in ship engineering.


Aluminum alloys for ships are mainly aluminum-magnesium alloys, aluminum-magnesium-silicon alloys and aluminum-zinc-magnesium alloys. According to the positions used, they are divided into aluminum alloys for upper outfitting and aluminum alloys for hull structure, in which the perch includes masts, portholes, chimneys, wheelhouses, etc., and the hull structure includes partition walls, ribs, keels, bottom outer plates and ship sides, etc. The aluminum alloy profiles commonly used for portholes in ship superstructure are 6063 aluminum alloy, and 6063 and 6061 aluminum alloy profiles are often used for masts and gangways. In addition, extruded aluminum-magnesium alloy is used for the wallboard, which can prevent deformation during welding and ensure more reasonable stress distribution. The application rate of Al-Mg alloys in ship hull is high, among which 5454 and 5052 aluminum alloys are the main materials for making decks.


Application in the field of civil ships.


The application of aluminum alloy in shipbuilding industry can be traced back to the end of 19th century, and it was first manufactured by European and American countries. However, the strength and corrosion resistance of only a few aluminum alloys were not dominant at that time, so they were not widely used. It was not until the rapid development of metallurgical industry and the appearance of aluminum-magnesium alloys with strong corrosion resistance that aluminum alloys received due attention in shipbuilding industry. By the middle of the 20th century, the application of aluminum alloy in civil ships reached a small peak period, and some achievements were made in related technologies of aluminum alloy, such as the development of aluminum alloy plates (5486-H32, 5456-H32), the extensive application of SXXX series 5054 alloy (made in Britain) as the inner liner of oil tankers, and the birth of aluminum -TTG welding technology, etc. In the middle and late 20th century, influenced by the declining price of aluminum and aluminum alloy, and the market put forward higher requirements for the welding technology and other properties of aluminum and aluminum alloy, the development of aluminum and aluminum alloy in the field of civil ships ushered in a new situation.


Application in the field of military ships.


The design of ship manufacturing follows the idea that the structure tends to be light. It is widely believed that the light ship structure has great advantages in controlling ship speed, operating precision and manufacturing cost, which can greatly reduce consumption and prolong the mileage of ships. Aluminum alloy can well meet the lightweight requirements of ships, so it has been widely used in the field of military ships, thus completing assault or search and rescue tasks and maintaining navigation safety. At present, military ship technology mainly includes fast attack boats, auxiliary military airships, patrol boats and so on.


Application in the field of workboat.


The requirements of working ships for aluminum alloy are different from those of other types of ships, mainly requiring them to have a long service life and low maintenance cost. The aluminum alloy work boat usually has a service life of several decades. Because its running strength in seawater is not high, the damage degree of external force to it is also low, thus reducing the maintenance cost of the work boat. For obsolete workboats, it is often because of their backward structure and technology that it is difficult to meet the requirements of workboats in the new situation, rather than the quality problem of aluminum alloy.


Application of aluminum alloy in ocean engineering.


Application of drill pipe in oil and gas exploitation.


In addition to its application in shipbuilding industry, aluminum alloy is also widely used in offshore engineering. For example, in the development of offshore oil resources, the drilling equipment used is usually made of aluminum alloy. Because the material of drilling equipment will significantly affect the exploitation efficiency of subsea oil resources, and because of the severe subsea oil exploitation environment, the maintenance of drill pipe in drilling equipment is very inconvenient, therefore, using aluminum alloy material to manufacture drill pipe can prolong the service life of drilling and production equipment, and has the advantages of strong impact resistance, light weight and low torque, which can effectively reduce the friction during exploitation and play a strong role in improving the drilling and production efficiency. In a word, the application of aluminum alloy in the exploitation of submarine petroleum resources can give full play to the advantages of aluminum alloy, and its application prospect is immeasurable.


Application in LNG (liquefied natural gas) cargo ship.


China’s oil and gas resources are concentrated, but people who need natural gas are distributed all over the country, and even need to be shipped overseas, which requires the storage tanks for LNG to have low temperature and good corrosion resistance. Nowadays, LNG cargo ships are the main means of transportation for natural gas in China. In the design of LNG ship storage tanks, it is necessary to ensure that LNG does not leak, ignite or corrode the storage tanks. Aluminum alloy is not only a low-temperature metal, but also has good strength and toughness, and has the characteristics of light weight, easy handling and corrosion resistance, which makes it have high application value in LNG ships.


Application in offshore helicopter platform.


In the past, the main material of offshore oil drilling platforms was steel. Although the strength of steel was high, due to the special nature of seawater, steel was inevitably faced with rusting and corrosion, resulting in short service life and limited application. Offshore helicopter platform is the infrastructure for the development of submarine oil resources, which can effectively ensure the safety of helicopter taking off and landing, thus maintaining good contact with land. Aluminum alloy is also widely used on helicopter platforms, because the helicopter platform deck has higher requirements in terms of its own weight and structural rigidity, while the aluminum structure is light in weight, can meet its requirements in other aspects, and has good corrosion resistance. In addition, the aluminum alloy helicopter platform can be spliced by profiles instead of welding, which can prolong its service life.


Application in marine wharf.


It is an important place for ships to dock, which requires high corrosion resistance, bearing capacity and strength, and aluminum alloy can perfectly meet these requirements. Therefore, floating bridges, aisles, gangways and floating docks in marine docks can be manufactured or welded with different types of aluminum alloys, and the floating docks and structures may not be chemically or painted during the production process.