The head during the quenching process, the alloy in the material changes. When the head is quenched, because of the rapid cooling, these vacancies are too late to be removed and are "fixed" in the crystal. The supersaturated solid solution of the head is in an unstable state, and the material must change to the equilibrium state. The existence of the change accelerates the dispersion rate of solute atoms, therefore accelerates the segregation of solute atoms. The production of head is usually carried out in converter and open hearth furnace. Converter usually produces the common variety, while the open hearth can produce all kinds of high quality steel. In recent years, the technology of oxygen top blown converter is developing rapidly, which can replace open - hearth steelmaking. By putting the molten steel into the ingot mould, the ingot of various sealing head factories can be obtained. After processed by pressure, the internal structure and inclusion distribution of the steel can be improved, so the steel with the same composition can better performance than the ingot.