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Se ti interessa guardare il nostro video in lingua italiana clicca questo link: • Find out more about our project: • Here are some products installed by our technicians: JAES is a company specialized in the maintenance of industrial plants with a customer support at 360 degrees, from the technical advice to maintenance, until final delivery of the industrial spare parts. Linkedin: Facebook: Our journey through Zanardi Fonderie’s production plant continues and in this video we will observe the ancient melting and casting process of the cast iron jets, a process which is still evolving today. In our previous video, we started with the design offices all the way to the coupling of the two green sand half moulds, ready to host the liquid cast iron. Today we will discover the process of melting and casting of the cast iron. Zanardi Fonderie plant has 3 electric induction melting furnaces operating at mains frequency with a capacity of about 28 tons and an installed power of 3,300 KW each. The ovens are loaded by vibrating loading platforms located in the rear part, while the liquid basic pig iron is poured from the front part of the oven which had been previously tipped. The filling materials used to realise the liquid-based cast iron bath(I don’t think it’s the correct definition) are mostly: - Pig iron - Steel scraps - Scraps of previous castings All these materials are stored in different compartments found in the raw material park and are transported to the loading wagons by an electromagnet equipped with a load cell semi-automatically maneuvered by the operator. In order to achieve a suitable chemical composition of the base cast iron, in addition to the three materials mentioned above, graphite, silicon carbide, silicon iron, copper, manganese iron, molybdenum iron can be loaded manually by foundry operators (Cure Oven Operators) ; this activity is necessary to get closer to the final cast iron composition. During the preparation phase of the base cast iron which precedes the pouring phase from the treatment ladle (or transport phase and within which the spheroidization reaction will take place), it is best practice to take samples from the bath to carry out the thermal analysis and obtain the samples for the chemical analysis, in order to monitor the conditions and the composition of the bath, if necessary, make corrections to reach the required target. The temperature in the oven is also monitored by an immersion thermocouple probe. The temperature must be constantly monitored, since after pouring the molten metal into the treatment ladle it will decrease during the transport phase (which includes spheroidization reaction, further ladle slag and pouring) from the ovens to the casting line. As anticipated, to transport the liquid cast iron, from the melting furnaces to the casting line, a ladle is used. It has a capacity of 3,000 kg, inside which the spheroidization reaction takes place by adding suitable ferroalloys (Fe-Si- Mg iron-silicon-magnesium, Ni-Mg nickel-magnesium). The ladle, maneuvered by a crane, before hosting the liquid base cast iron, passes through a loading station where spheroidizing alloys and corrective materials for the composition are introduced (for example correction ferroalloys such as Fe-Si Ferro- Silicon, pure metals such as Cu Copper and Ni Nickel); this is necessary to reach the optimal conditions to obtain the spheroidization reaction and the chemical composition of the final cast iron. During the pouring, the (very violent) spheroidization reaction begins inside the treatment ladle, which enables the formation and growth of graphite particles in a spheroidal shape rather than lamellar shape when solidifying. Before pouring the liquid cast iron from the treatment ladle to the casting one, it is necessary to carry out a second ladle slag removal since the spheroidization reaction produces a certain quantity of waste. To produce graphite cast iron, it is necessary to implement various strategies intended to inhibit the formation of cementite in each area of the casting to be produced. A very effective but complex intervention consists in intervening on the chemical composition using elements called “graphitizing“ such as silicon. Another type of intervention on the nucleation mechanisms, more effective even if delicate, consists of introducing heterogeneous preferential nucleation sites of graphite into the liquid cast iron. This is the process known by the name of inoculation which enables to eliminate the formation of cementite in thin areas of the cast iron and to control and make the type and distribution of the graphite particles homogeneous within the casting and therefore its mechanical characteristics. During the ...VISIT YOUR WEB SITE!
