Steel manufacturing is an extremely important industry that has a huge impact on the global economy. According to a report published by World Steel Association, global steel production contributes about $2.9 trillion to the world’s economic activity every year.
Steel has been the most relied-upon material in the manufacturing and construction markets since the 1800s supporting millions of jobs worldwide. Structural steel is being used in shipbuilding, the automotive industry, the mining industry, and energy production and transmission industries.
Steel manufacturing has really come a long way thanks to advancements in technology. In this article, we are going to look at the history of steel production and the latest methods that are being employed for this purpose.
We will also look at some of the main applications that involve the use of structural steel so stay with us till the end.
What is Structural Steel?
This is a process wherein the shape of steel is manipulated to generate different products for a variety of applications. In this process, different pieces of steel are combined or molded to create products needed for construction, industrial equipment, and other use cases.
History of Structural Steel Fabrication Process
The discovery of steel dates back to the iron age i.e., about 1200 BC. Iron was first mined in Europe and Central Asia and the humans of this age used this material to make weapons and tools in a practice that was then known as ferrous metallurgy.
Slowly, iron products started to evolve when blacksmiths started producing wrought iron goods. They figured out that if they heat up the iron ore and use a hammer and anvil to beat it enough time, it removes the impurities from the metal giving you a more durable and malleable iron product.
In ancient China, Iron age metallurgists used large furnaces to heat up the iron. This would melt the substance converting it into a liquid phase and then they added wood fuel to this phase.
This melted liquid would then be shifted into molds and then would be left to harden. This process was used to create cooking tools and other accessories used for construction.
This process produces cast iron which is more durable than wrought iron. However, the former is more brittle which makes it hard to shape and bend the material to a great extent.
After cast iron, blacksmiths in the Central Europe region started coating wrought iron products with charcoal which improved the strength of the material while maintaining its flexibility. After this, the iron manufacturing process went through a final iteration. This is the method that resembles today’s metal fabrication process to a great extent.
In India, ironworkers came up with a smelting process where they mixed a proper ratio of iron and carbon using crucibles. They would blend iron and charcoal pieces in clay containers at extremely high temperatures using special furnaces.
In the process, the iron would melt and the carbon atoms from charcoal get absorbed in it. Upon cooling, you get what we now call Steel which is basically an iron-carbon alloy.
Since the discovery of iron-carbon alloy, many countries around the world have scaled up their steel production practices. Humans have looked to perfect the steel fabrication process for centuries and the main goal here is to not only produce steel in greater quantity but also to produce it in pure form and with more strength as well as flexibility.
How is Steel Made Today?
The modern-day structural steel fabrication process began in 1856 using a method called the Bessemer process. This was arguably the first process used to produce steel in bulk. Some historians are of the view that two different inventors from the UK and Pittsburgh simultaneously came up with a process for steel production involving the removal of iron’s impurities using an air blast.
After this development, other researchers started working to perfect this process. They figured out a way to use the air blast technique to keep the carbon content of steel maintained while fully eliminating the impurities. After that, this process evolved into a highly cost-effective approach to mass-produce very high-quality steel.
Here are the two main processes that are being used today to manufacture steel
1. Blast Furnace:
This process, sometimes also referred to as BOP or basic oxygen process involves the mixing of raw iron ore with very small quantities of steel scrap metal into a furnace. After that oxygen is allowed into the furnace which raises the temperature.
In this process, the scrap metal melts into a liquid and the impurities of iron are oxidized and then evaporated completely. Moreover, the high temperature decreases the carbon content to an ideal ratio which results in liquid steel.
2. Electric Arc Furnace:
In the electric arc furnace method, high-current electric arcs from electrodes are used to convert large quantities of steel scraps into a liquid phase. As the steel scraps are melting, other ferroalloys are added until the desired ratio of steel to these alloys is reached. This leads to the formation of stainless steel. To further purify the steel, oxygen is blasted in the furnace and then lime, and fluorspar are added.
These combine with the impurities present in steel effectively turning into slag. This slag floats on top of the molten steel from where it is taken out leaving pure steel behind.
Stages Involved in Structural Steel Manufacturing
The operations involved in structural steel manufacturing can be divided into three main segments i.e., cutting, bending, and welding. These processes transform raw materials into specific steel products according to the application requirements.
In the cutting stage, different processes like plasma cutting, laser cutting, or water jet cutting are used to separate parts of the original steel to create the desired shape.
In the bending stage, either manual labor or specific machinery is used to change the material’s shape to fulfill specific needs.
In the final stage called welding, different pieces of steel are combined into a single piece by the application of high heat. Other processes that can be used to join pieces of steel together include rivet construction or the use of adhesives.
However, welding is considered the most viable option since it allows you to create strong foundations and join much more complex pieces together more efficiently. Welding is cost-effective as compared to other means of combining steel pieces which is another reason why it is preferred by most industries.
Structural Steel Manufacturing – Benefits
There are certain applications where the use of structural steel requires extreme care. However, this complicated process, if carried out properly, can give you many benefits.
Following are some of the main benefits of using structural steel in commercial or domestic projects
The use of structural steel significantly reduces the on-site work. Steel structures usually come prefabricated which means there is no need to spend any time assembling them after the delivery.
Steel has various special properties that make it much stronger and more durable than other materials while weighing considerably less.
Steel structures provide a good contrast which makes these stand out, particularly in construction applications. The visuals of this material are much better than concrete, wood, and other materials incorporated in construction projects.
Steel is strong as well as low maintenance which gives it a long life as compared to other materials. Steel has very few weaknesses which include low resistance to corrosion and high heat.
It is very easy to customize specific structural steel parts due to the high malleability of this material. It is also possible to add more properties to steel by incorporating other metals into its mixture.
Steel is comparatively cheaper than other similar options used for similar applications in construction and other fields.
7. Environmental Effects:
Steel can be recycled and reused with relative ease. This reduces emissions making it a much more environmentally friendly material.
Applications of Structural Steel Procedures in Various Fields
There are a lot of fields that are benefiting greatly from appliances and structures made from steel. For example, in the mining industry, structural steel is used to produce pipes, rods, beams, fittings, and other excavation tools.
Shipbuilding is another industry where structural steel is extensively used for designing and creating supertankers, ferries, recreational boats, etc. In the automotive industry, this material is used in the manufacture of engines as well as their related safety features.
The energy industry also uses structural steel procedures for manufacturing various technologies including oil platforms, transmission towers, wind turbines, pipelines, and much more.
Steel alloys and structures are also being used in the aerospace industry to create external aircraft parts as well as internal machinery. The most common applications of structural steel are found in the construction industry where it is employed to create tools such as steel ladders, industrial stairs, platforms, handrails, etc.
On the whole, the manufacturing process of structural steel is not that complex when you compare it with other metalworking processes and standards. Still, there are certain details, stages, and applications involved in the process that need special care and attention.
In this article, we tried to cover as much information about the origins, manufacturing process, benefits, and applications of structural steel as possible. We hope you find this information useful and that now you know what processes and methods are involved in the fabrication and design of structural steel.
Contact Power Solutions Industries for industrial-grade structural steel fabrication services in the MENA region.