What is the hydrogen content of cast iron melted by induction melting furnace?

In gray cast iron, hydrogen is a harmful element, the lower the content, the better. Due to the high content of carbon and silicon in cast iron, the solubility of hydrogen in them is low. In the molten iron melted in the cupola, the hydrogen content is generally 0.0002~0.0004%. In the molten iron melted by the induction melting furnace, because the interface between the metal and the furnace gas is small, the hydrogen content is generally lower, about 0.0002%. The hydrogen produced by the casting is less likely to cause porosity and pinholes in the casting.