Pig iron is a Fe based alloy generally having a carbon content of 3-5 percent, containing other elements too and produced by a metallurgical process from iron ores bought only from abroad. It is an intermediate product that is processed to be either steel or iron cast product. So, according to its way of production we can speak about steel-making (white) pig iron, as well as foundry (grey) pig iron. This latter one has not been produced in the ironworks for years.

One of the most important iron containing materials required for production is iron ore pellet. Currently this is primarily purchased from Russian sources. Slagging material (limestone) and blast-furnace coke from DBK Kokszoló Kft. (DBK Coking Plant Ltd.) is added to this, as well as to sinter and scrap. This is burnt by preheated air (at a temperature of 1000-1150 oC) and pig iron is reduced by the gas produced in this way, as well as by coke. This can be hardly formed in its hot or cold states. Therefore, at first it was an unwanted product and only simple cast products (balls) were produced from it. However, it became very significant with the development of the steel-making process proceeding from pig iron production.

Blast-furnace gas is produced as a residual product (its main components are carbon dioxide, carbon monoxide, nitrogen and hydrogen) that is used for energy production, furnace heating and is recycled into the system for preheating. The product of the work of blast-furnace men is required by the steel-making plant in the form of pig iron, and solid pigs deriving from the casting machine are processed by several foundries in the country.