Steel Production: From Pig Iron and Scrap to Finished Products

Slag and pig iron pass through an LD converter for forming into steel ingots. Around this ring furnace, wind is extracted by hot air.

Operation of the Converter

The converter leans over the oven, and flux and sometimes cast iron scrap are added. It is then set to vertical, and a lance is lowered to inject oxygen into the molten metal. The impurities are burned. The converter leans out of the furnace, and the slag that floats on the steel is poured over the spoon. Alloys and carbon are added.

Obtaining Steel Through Scrap

To convert scrap steel, an electric oven is used. Its most important parts are:

• Electric transformer: Transforms alternating current to direct current and voltage to 900V.
• Arms of the electrodes: The electrodes can approach or move away from the scrap for the electric arc jump.
• Portico with hydraulic arms: To remove and put the lid of the electric furnace to enter the scrap, alloys, and flux.
• Vent chilled: Smoke leads to a filter, removing suspended particles.
• Oscillating structure: To tilt the furnace to remove the molten steel.

Main Features

• The load of a furnace is about 100 tons.
• The interior is lined with refractory brick.
• Each batch takes about 50 minutes.

The Operation

1. The lid is removed, and the scrap and flux are inserted.
2. The oven is closed, and the electrodes are close to the scrap for the electric arc to jump and start to melt the scrap.
3. When the scrap is melted, oxygen is injected to eliminate undesirable elements.
4. The oven leans to remove the slag. Then, carbon and ferroalloys are added and heated until dissolved.
5. The furnace tilts and is poured from a spoon.

Steel Castings

Conventional casting of steel is to pour the liquid on molds to the shape of the piece that is desired, allow to cool, and remove the piece.

Continuous casting: Steel is poured liquid over a bottomless mold and lid.

Casting on molds: Ferrous products are cast in bivalve molds and cooled.

Lamination: Involves passing the material between two rollers that rotate at the same speed but in opposite directions, making it finer and longer.

Classification of Non-Ferrous Metals

• Heavy: Density is greater than or equal to 5 kg/dm³ (Tin, copper, zinc, lead, chromium, nickel, and tungsten).
• Light: Its density is between 2 and 5 kg/dm³ (Aluminum and titanium).
• Ultralight: Its density is less than 2 kg/dm³ (Magnesium and beryllium).