ã€China Aluminum Industry Network】 1. Recycling, baking and sifting of aluminum chips Recycling of aluminum scrap When cutting aluminum, the chips account for about 20% of the weight of the casting, up to about 30%. At present, the aluminum price on the market is about 15,000 yuan/ton, so the aluminum scraps in the machining process of piston products can reduce the production cost and have good economic benefits. Aluminum scrap recycling work should follow the following one: recycling, baking and sifting of aluminum scrap 1. Recycling of aluminum scrap When cutting aluminum, the chips account for about 20% of the weight of the casting, up to about 30%. At present, the aluminum price on the market is about 15,000 yuan/ton, so the aluminum scraps in the machining process of piston products can reduce the production cost and have good economic benefits. Aluminum scrap recycling work should pay attention to the following points: (1) When a certain material grade of the workpiece is processed, it should be promptly received by the country to prevent aluminum scraping. During recycling, aluminum scraps in the chassis of various machine tools that participate in cutting should be cleaned. (2) Aluminum scraps to be recycled should be stacked strictly in the specified bins of the storage yard according to the classification of the grades, and the aluminum scraps should be marked. The type of brand, when conditions are met, should be remelted in time to avoid mixing numbers. (3) It should be avoided that dust, such as sediment and cotton yarn, is mixed with aluminum chips.
2. The preheated baked aluminum scraps of aluminum scrap carry a lot of oil and moisture. Oil and moisture from the machining process, or other processes (such as in order to improve the uniformity of the failure of the piston parts, the temperature of the oil furnace furnace temperature failure process), if the poor preservation of oxidation corrosion serious, so it should be timely preheating drying grilled. The baking temperature of aluminum shavings must be determined according to various factors. If the temperature is too high, not only the heat loss will be great, but it will also cause strong oxidation of aluminum chips. Therefore, the general baking temperature should be brewed between 250 ~ 300C. A simple way to bake aluminum chips is to place the aluminum chips on a steel plate and heat them until they do not emit smoke. Aluminum scraps can also be put into the "roasting car", pushed into the drying kiln for baking or adding the aluminum scraps to the industrial frequency furnace, and baked in a cast iron pot, so that the oil and the volatile oil can be evaporated at high temperature forever. And burning, and then melting (of course, this method has the disadvantage of poor working conditions, smoke filled the workshop) J aluminum preheat baking can not only remove the oil and water in the aluminum shavings, but also can shorten the melting time, in the reduction of power consumption At the same time, it can increase the productivity of melting equipment and reduce the cost of melting (remelting).
(3) Aluminum sifting After the aluminum swarf is sifted, it is better to conduct sizing treatment to remove the oxidized powder or the entrapped mud sand and the steel shavings that may be generated. However, if the aluminum shavings are “fresh†and clean, and the baking temperature is normal, it is not necessary to screen. Through the above-prepared aluminum scrap, it can be used for remelting remelting, casting into a reclaimed ingot for use in smelting aluminum alloys.
Second, the aluminum smelting in the industrial frequency furnace smelting aluminum smelting methods are generally two kinds: (1) two smelting method: by the previous is the aluminum swarf melting into ingots (recovery ingots) according to their chemical composition Stacking; in the second smelting, the recycled ingots are smelted into the finished product. (2) Direct addition method: When using this method, the aluminum chips can be directly baked in the furnace (using the waste heat or the bottom temperature), and after the aluminum chips are dried, the temperature is increased to melt and added to the various materials. The main and auxiliary materials are smelted. Compared with the two methods, twice smelting, power consumption and elemental burning are larger. The management work is cumbersome and wastes manpower and material resources. The second method is only applicable to the continuous production of a brand of aluminum castings. In the same period of production of multi-god brand aluminum, the use of the first method is more applicable.