Today a few iron and steel makers produce a foundry pig iron for casting with iron ore that is mainly produced from home land according to demand of foundry pig iron for casting in rapid growth of casting industry field. Some men try to make to reduce of casting cost which uses a little of lathe chip of steel that out-puted from machine shop. This paper is discussed a few of characters which arise on operation of M. B. C. to make a foundry pig iron with 80% lathe chip of steel and 20% light steel scrap.