High-efficiency and energy-saving short-process continuous casting aluminum alloy production process

Abstract

The invention discloses a high-efficiency and energy-saving short-flow continuous casting aluminum alloy production process, which includes the following steps: the first step is to prepare an aluminum alloy solution by alloying in a vacuum bag; the second step is to carry out nitrogen refining on the aluminum alloy solution in a low-level furnace , to remove the scum on the surface; the third step, after removing the scum, the aluminum alloy solution is degassed and slag-removed by an online degassing and slag removal device to prepare the aluminum alloy solution to be poured; the fourth step is to cast the aluminum alloy solution to be poured to obtain the aluminum alloy solution alloy ingot. The present invention saves the natural gas heating energy needed for preheating the high-level furnace and alloying after adding aluminum, and greatly reduces the production energy consumption; compared with the existing aluminum alloy production process, the production time is optimized from about 5 hours to about 3 One heat per hour greatly improves production efficiency; reduces raw material and labor costs; comprehensively reduces original casting loss by 0.5%.

Description

Technical field: [0001] The invention relates to a casting aluminum alloy production process, in particular to a high-efficiency, energy-saving short-flow continuous casting aluminum alloy production process. Background technique: [0002] The production process of the existing cast aluminum alloy ingots generally includes process steps such as compounding of aluminum alloy components, alloying, refining with refining agent, and slag removal in the furnace. The current production process of casting aluminum alloy ingots has problems such as high energy consumption, large heat loss, high casting loss, and low production efficiency. Taking the A356 cast aluminum alloy as an example, the production process is as follows: adding metal silicon into the high-position furnace and spreading it on the bottom of the furnace, heating up the furnace to preheat the metal silicon, and pouring high-temperature primary aluminum liquid into the furnace from a vacuum bag , and add titanium a...

AI Technical Summary

Problems solved by technology

[0003] (1) The preheating of metal silicon and the baking in the furnace require a certain furnace temperature in the furnace, and the baking of metal silicon needs to continuously raise the temperature of the smelting furnace to maintain a constant temperature in the furnace, which increases the production energy consumption

[0004] (2) After the molten aluminum in the vacuum bag is poured into the high-level furnace, the temperature drops to about 800°C. Compared with the raw aluminum liquid at 940°C that has just been pumped in, more than 100°C was wasted in the process of transportation and furnace reversal, and the heat loss is high;

[0005] (3) It takes a long time to melt silicon in the high-level furnace, with an average of more than 180 minutes per furnace. The temperature required for aluminum to completely dissolve metal silicon needs to reach above 700°C, and the temperature of the molten aluminum in the vacuum bag is poured into the high-level furnace. The temperature drops to about 800°C , in the process of melting silicon, the heat of the original aluminum liquid is still being lost, which cannot meet the temperature requirements in the long-term melting process of silicon, so it is necessary to heat the high-level furnace to maintain the reaction temperature, which further increases the production energy consumption;

[0006] (4) The refining process of the low-level furnace will increase the original casting loss of the molten aluminum, the cost of refining agent and refining gas will be high, and it will consume a lot of manpower and time; It is easy to carry aluminum; the refining agent is generally composed of chloride salt, the aluminum ash extracted after refining cannot be recycled, the cost of hazardous waste treatment is high, and it is easy to cause environmental pollution

[0007] (5) The vacuum bag conveys the raw aluminum liquid and the alloying of the molten silicon is carried out step by step, and the two process steps take a long time, resulting in a long time-consuming process of the entire casting production process and low production efficiency

[0008] (6) The homogenization of the melt composition depends on the particle size of metal silicon. The grade of metal silicon used in most aluminum alloy ingot casting production is 441, and the particle size of metal silicon is 50-150mm. The contact area of ​​the aluminum liquid increases the reaction time, and it takes about 120 minutes to make the silicon molecules evenly diffuse into the molten aluminum body and alloy it. Because the silicon melting time is long, the average time per furnace is about 180 minutes or more, and the production efficiency is low.

[0009] (7) The high-level furnace of the melting furnace is in the process of melting silicon and removing slag for a long time, resulting in 1.8% of the original casting loss

Images