Steel manufacturing Brisbane companies have an important role in the Australian economy since the 19th century with its increased need for steel in rail and other industries. It’s not only related to history but also possibilities in future for steel manufacturing Brisbane companies with modern steel manufacturing technologies and models.
Though started its journey in the late 19th century, not to mention steel manufacturing Brisbane industry has seen how steel manufacturing process has been evolved over the period. Steel manufacturing is nothing but lowering the carbon content in iron by using oxygen in it. However, modern steel manufacturing process follows several steps resulting in more good quality products generation.
In this article, we will discuss on how steel manufacturing Brisbane companies use modern steel manufacturing processes.
What are the two modern steel manufacturing processes?
Modern steel manufacturing follows two processes:
- Basic oxygen steelmaking (BOS)
- Electric arc furnaces (EAF)
Both Primary steel making and Secondary steelmaking use the methods mentioned above. Unlike traditional method, today steel manufacturing Brisbane companies use coal, iron ore and limestone in addition to the traditional raw materials.
What are the steps followed in modern steel manufacturing?
Whether it is primary steel making or secondary steel making, every steel manufacturing Brisbane company follows either Basic oxygen steelmaking (BOS) or Electric arc furnaces (EAF) process. Below steps are followed in steel manufacturing:
Step 1: Ironmaking
Ironmaking is used as the very first step of the steel manufacturing process. In this step raw inputs like coke, iron ore, and lime are melted in a blast furnace. The limestone along with impurities and molten iron forms a liquid ‘slag.’ This Slag is lighter than the metal. Hence it floats on top of it. The melted iron which is also known as hot metal contains 4 -4.5 percent carbon along with other impurities which makes it brittle.
Step 2: Primary steelmaking
For Primary steelmaking steel manufacturing Brisbane manufactures use either BOS (Basic Oxygen Furnace) or the more modern EAF (Electric Arc Furnace) method.
- Method 1: BOS (Basic Oxygen Furnace)
In this method, manufacturers add recycled scrap steel with the molten iron in a converter. The proportions at which the metals are mixed vary depending on the process and the type of the required steel.
At high temperature and pressure, water cooled high purity oxygen is blown to the metal. This reduces the carbon content to 0 -1.5 percent. During the process, lime is also added as a flux to remove other oxidized impurities from the floating layer of the slag.
- Method 2: Electric Arc Furnace (EAF)
The Electric Arc Furnace (EAF) is used for high-quality manufacturing steel by using cold scrap metal. Not to mention cold scrap steel provides more precise control over the composition. Additionally using modern electric arc furnaces steel manufacturing Brisbane manufactures can make nearly 150 tonnes of steel in a single melt.
In an Electric Arc Furnace, recycled steel scrap is fed with an application of high- temperatures (up to 1650 C). This melts the metal and converts it to high-quality steel.
Step 3: Secondary steelmaking
Once the molten metal is generated by applying the BOS or EAF method, further treatment is done on it to adjust the composition depending on the steel quality requirement. This is known as secondary steel manufacturing. The treatment involves adding or removing specific elements along with the manipulation of the temperature and production environment. There are different types of secondary steel making process that are used in steel manufacturing Brisbane industry. These are:
- Ladle furnace
- Ladle injection
- CAS-OB (composition adjustment by sealed argon bubbling with oxygen blowing)
Step 4: Continuous casting
Before the final product is produced from molten steel, it needs to be solidified and formed into some basic shapes like billets, blooms or slabs. For this purpose, continuous casting is applied to it.
In the casting process, the molten steel is cooled down to mold which creates a thin steel shell for solidification. Therefore the shell strand is withdrawn by guided rolls. Once it is fully cooled, it takes a solidified shape. Then the strand is cut into required lengths. It could be strip, beams or billets.
Finally, the steel manufacturing Brisbane manufacturers apply secondary forming techniques which give the steel its final shape. The techniques commonly used are:
- Machining or drilling)
- Shaping or cold rolling
- Coating or galvanizing
- Joining or welding
- Surface treatment or carburizing
- Heat treatment or tempering
As we have discussed on the steel manufacturing process, it indicates that the overall process must maintain the quality to experience the best outcome. However, with an experienced and quality steel manufacturer, we can expect a quality product as per the desired requirements.