how to use recarburizer

The characteristics of high-quality recarburizer:

1. Performance excellent and stability.

2. The particle size is moderate, the porosity is large, and the absorption rate is fast.

3. The chemical composition is pure, high-carbon, low-sulfur, minimal harmful components, and high absorption rate.

4. The product has a good graphite crystal structure and improves the nucleation ability of the original molten iron. Increase the number of nodular cast iron ink balls during incubation, and increase graphite nuclei in electric furnace molten iron. Refine and homogenize the distribution of graphite in castings.

It is generally believed that the higher the molten iron temperature and the longer the action time, the higher the carbon absorption rate. But the reality is just the opposite. In the induction furnace, carbon is increased at low temperature and silicon is increased at high temperature. That is, at high temperature, instead of increasing carbon, it reduces carbon,this is because: (1)graphite carbon is mainly lost by gas-phase diffusion into the atmosphere outside the furnace; (2)the oxidation of molten iron is related to the balance of C-Si-O. The CO in the molten iron is continuously oxidized to CO2, and CO2 will be reduced by C, the CO and CO2 gas produced by the reaction float up and overflow the surface of the molten iron, reducing the carbon content in the molten iron.The reaction rate is related to the equilibrium temperature, and the equilibrium temperature varies with the carbon and silicon content. For ductile iron raw molten iron, the equilibrium temperature is about 1450℃±20℃, and gray iron raw molten iron is about 1400℃±20℃. The oxidation of carbon in the molten iron becomes severe above the equilibrium temperature. As a result of the reaction, the carbon in the molten iron is continuously burned by oxidation, and the burn loss of silicon is reduced. At this time, the recarburizer added on the surface of the molten iron balances the carbon increase and decrease in the molten iron.

Based on the above analysis, the following is the correct way to use the recarburizer in the induction furnace:

1.Using an electric furnace above 5T, the raw material is single and stable, we recommend the dispersed addition method. According to the requirements of carbon content and the proportion of ingredients, add the recarburizer and metal charge together with the batch materials into the lower part of the electric furnace, one layer of metal charge and one layer of recarburizer, the carbon absorption rate can reach 90%-95% .Do not slag when the recarburizer is melted, otherwise it will be easily wrapped in the waste residue and affect the absorption of carbon;

2.Using about 3T intermediate frequency induction electric furnace, the raw material is single and stable, we recommend the concentrated addition method. When the molten iron is first melted in the furnace or a small amount of molten iron remains, add the recarburizer to be added to the surface of the molten iron at one time, and immediately add the metal charge to press all the recarburizer into the molten iron to make the recarburizer and molten iron fully contact , The absorption rate is above 90%;

3.If using a small intermediate frequency electric furnace, the raw material contains pig iron and other high-carbon materials, we recommend fine adjustment of the recarburizer. After the steel/hot metal is melted, the carbon content can be adjusted and can be added to the surface of the steel/hot metal. The product can be dissolved and absorbed by the eddy current stirring or manual stirring of the molten steel during electric furnace melting. The carbon absorption rate is about 93%.

Choosing appropriate recarburizer can help reduce smelting production costs, improve the quality of smelted metals and castings, and allow smelting metal plants and foundries to obtain economic benefits and high quality. Anyang Huatuo Metallurgy can supply various recarburizer such as CPC,GPC,graphite carbon columnar etc for cast iron, always adhere to quality first, any require just contact us.