High ash content has an inhibitory effect on carbon increase and can also increase the amount of slag, thereby prolonging operation time, increasing power consumption, and increasing labor during the smelting process. Using a trench type induction furnace, if adding a carburetor to the furnace, especially low ash varieties should be selected to avoid oxide accumulation in the trench and affecting electrical efficiency. From the perspective of carbon efficiency, we can consider that of course, we hope that the fixed carbon content of the carburetor is higher and the ash content is lower. However, at the same time, enterprises also need to consider the factors of social management costs and the impact on the quality of molten iron. The addition method of carburizing agent also has a significant impact on the carburizing efficiency.

a. Carburizer is added to the furnace during loading

When loading, mix the carburizing agent with the furnace material and place it in the bottom and middle of an induction controlled electric furnace, which has a high carburizing efficiency. Regarding the carburizing efficiency of different carburizing agents, some people have conducted comparative experiments while keeping other conditions unchanged. The main points are summarized as follows: melting gray cast iron in a coreless induction furnace, the target carbon equivalent of cast iron is 0.3% (C3.4%, Si1.9%, Mn0.55%). The proportion of furnace materials is: cast iron 16%, return material 30%, scrap 52%, and carburizing agent 2%.

b. Adding carburetor during ironing

Adding a carburetor to the ladle during casting has a much lower carburetion efficiency than adding it to the furnace. Someone has conducted comparative experiments by adding different carburetors to the bag, and the key points are as follows: the melted cast iron is low-carbon equivalent cast iron, with a target composition of C 2.55%; Si 1.7%; Mn 0.4%. When casting iron, the temperature of the molten iron is between 1510 and 1530 ℃.

2. Sulfur content

When melting ductile iron, low-carbon carburetors with low sulfur content should be used. Although the price of low-carbon carburetors is high, they are necessary for us.

When melting gray cast iron, it is advisable to use carburetors with higher sulfur content. In this way, not only can costs be reduced, but the sulfur contained in it can also be utilized to enhance the responsiveness of molten iron to inoculation treatment, resulting in high-quality metallurgical castings. Under such economic conditions, one-sided pursuit of "high quality" carburetors and selection of low sulfur brands can not only increase enterprise management costs, but also have a negative impact on product and service quality.