5083 Cast Aluminum Plate for LNG Tank

 There are many types and shapes of tank trucks. Some tanks have very large volumes, such as 28,000L storage tanks on LNG ships. Under certain conditions, the weight of the tank body becomes the decisive factor affecting the quality of the tank car. For this reason, as long as aluminum and aluminum alloys have no effect on the quality of the transported materials, they must be welded with aluminum or aluminum alloy plates to reduce the weight of the vehicles achieve the goals of energy saving, emission reduction and environmental protection.

LNG carrier refers to a special ship that transports LNG (Liquefied natural gas) from the liquefaction plant to the receiving terminal. The main component of liquefied natural gas is methane. For the convenience of transportation, it is usually liquefied by freezing at very low temperature (-165°C) under normal pressure. The critical temperature for liquefaction of natural gas is -164°C at one atmospheric pressure. At such a low temperature, general marine carbon steel is brittle, so the liquid cargo tanks of LNG ships can only be made of expensive nickel alloy steel or Al alloy 5083.

The 5000 series aluminum alloys have good corrosion resistance and weldability. The tank body made of aluminum alloy can transport various liquids or liquefied gas without any protective coating inside, and because there is no corrosion, the oil quality is guaranteed.

The recycling value of the tank body is also higher after it is forced to be scrapped. At the same time, because the aluminum alloy has good electrical conductivity, it rarely accumulates static electricity on the tank body, so it will not generate sparks and cause an explosion. The momentary power produced by the collision will not cause the tank to crack and cause leakage.

The biggest difference between aluminum and steel in terms of the relationship between performance and temperature is that steel has low temperature brittleness, while aluminum and aluminum alloys do not. Therefore, aluminum alloy has become a good material for manufacturing cryogenic equipment and facilities. The tank trucks transporting liquefied natural gas and the large tanks for storing liquefied natural gas can be welded with aluminum alloy 5083 cast aluminum plate with O temper.

The reason why 5083 aluminum plate can be used for this application because it has the following features: 5083 belongs to the Al-Mg alloy and has good corrosion resistance, excellent weldability, good cold workability, and medium strength.

The 5083 cast aluminum plate for LNG storage tanks is a high-quality material for manufacturing liquefied natural gas storage tanks. Not only does it have ultra-low temperature structural materials, but it is also easy to process and form, and has good weldability and high recovery rate.

Original source: https://www.aluminium-tanker-plate.com/a/5083-cast-aluminum-plate-for-lng-tank.html

The Manufacturing Process of Aluminium 5083 H321

 The 5083 aluminum alloy sheet has many advantages such as light weight, medium strength, and easy forming. It can be used in the manufacture of automobile parts, ships and truck tank. However, 5083 aluminum alloy has a relatively high Mg content. It is easy to precipitate β phase (Mg2Al3) at the grain boundary when placed at room temperature for a long time. The precipitation of β phase will make the material age soften.

In order to reduce the adverse effects of β phase precipitation, aluminum 5083 h321 was developed. Stabilizing annealing is carried out on the cold-deformed 5083 aluminum alloy sheet, so that part of Mg can be uniformly precipitated in the alloy in the form of β phase, ensuring that the material after aging softening still meets the performance requirements.

In the manufacturing process of 5083 h321 sheet, the amount of cold deformation after recrystallization annealing, and the temperature and time of stabilization annealing after cold deformation are three key process parameters that affect the final properties of the 5083 aluminum plate.

During the cold deformation process, as the amount of cold deformation increases, the plate lattice distortion and the degree of grain breakage will increase, and the large grains will be elongated along the rolling direction to form a fiber or band-like structure, and a large number of bits will be generated inside the grains. The interaction between dislocations is enhanced, therefore, the strength of the alloy increases.

With the increase of the annealing temperature and the extension of the holding time of the stabilized annealing, the tensile strength and the yield strength will decrease. This is due to the large deformation storage energy accumulated after the cold working of the plate, which causes recovery and softening during annealing. Partial work hardening is eliminated, so the strength is reduced and the elongation is increased.

As the amount of deformation increases, the intergranular corrosion resistance of 5083-H321 sheet decreases, and when the amount of deformation and the stabilization annealing time are the same, the intergranular corrosion resistance of the plate depends on the temperature of the stabilization annealing.A cold deformation of 20% and a stabilized annealing system of 180℃/2h are the best production processes for the 3 mm 5083 aluminum sheet.

Original source: https://www.aluminumtankerplate.com/a/the-manufacturing-process-of-aluminium-5083-h321.html