In the smelting process of iron and steel products, the melting loss of carbon element in molten iron is often increased due to factors such as smelting time and long overheating time, resulting in that the carbon content in molten iron cannot reach the theoretical value expected by refining.
In order to make up the amount of carbon lost in the smelting process of iron and steel, carbon-containing substances added are called carburizer. Petroleum coking agent can be used in casting gray cast iron, the carbon content is generally 96~99%.
There are many kinds of carburizing agent raw materials, carburizing agent manufacturers production process is also different, there are wood carbon, coal carbon, coke, graphite, etc. High quality carburizer generally refers to the graphitized carburizer, under high temperature conditions, the arrangement of carbon atoms shows the microscopic morphology of graphite. Graphitization can reduce the content of impurities in the carburizer, increase the carbon content of carburizer and reduce the sulfur content.
There are many kinds of carburizer, and the quality index of carburizer is uniform. The following is the method to distinguish the quality of carburizer:
1. Water content: The water content of carburizer should be as low as possible, and the water content should be less than 1%.
2. Ash content: The ash index of carburizer should be as low as possible. The ash content of calcined petroleum coke carburizer is relatively low, about 0.5~1%.
3, volatilization: volatilization is the ineffective part of the carburizer, volatilization depends on the calcination or coke temperature of the carburizer and the treatment process, properly processed carburizer volatilization is below 0.5%.
4. Fixed carbon: The fixed carbon of the carburizer is the really useful part of the carburizer, the higher the carbon value, the better. According to the fixed carbon index value of the carburizer, the carburizer can be divided into different grades, such as 95%, 98.5%, 99%, etc.
5. Sulfur content: The sulfur content of carburizer is an important harmful element, and the lower the value, the better. The sulfur content of carburizer depends on the sulfur content of carburizer raw material and calcining temperature