Classification

Steel mills worldwide, according to their production process, are classified as:

  • Integrated –those operating the three basic stages: reduction, refining and lamination; are engaged in the whole production process and produce steel.
  • Semi-integrated – those operating two stages: refining and lamination. These mills start with pig iron, sponge iron, or metallic scrap purchased from third parties to transform them into steel in electric steel shops for further lamination.

Furthermore, the mills may also be classified based on the predominant output of their production lines, as follows:

  • Semi-finished (plates, blooms and billets)
  • Carbon flat steel (plates and coils)
  • Special/alloy flat steel (plates and coils)
  • Carbon long steel (bars, shapes, wire rod, rods, wires and seamless tubes and pipes)
  • Special/alloy long steel (bars, wire rod, wires and seamless tubes and pipes)

There are also production units named non-integrated, which operate only one stage of the process: processing (hot-rolling or drawing) or reduction.

Hot-rolling:

Includes re-rollers, generally of sheets and billets, purchased from integrated or semi-integrated mills, and companies re-rolling scrap material.

There are also small units dedicated exclusively to the production of steel for casthouses.

Drawing:

Includes drawing mills, producers of wires and bars which use wire rod as raw material.

Reduction:

Pig iron producers, which use vegetable coal in blast furnaces for ore reduction, which constitutes a distinct industrial activity..

According to CNAE / IBGE (national standardization tool of the country’s economic activity codes), Metallurgy is a division within Transformation Industries. This economic activity encompasses the conversion of ferrous and non-ferrous ores into metallurgic products and intermediary process products.

Steelmaking, the sector encompassing the production of steel in the form of semi-finished, hot-rolled, re-rolled and drawn goods and seamless pipes and tubes, is classified as a specific group within the metallurgy division, including other co-related activities. Within metallurgy, independent pig iron and ferroalloy producers comprise another group.