Building a stainless steel product from the ground up involves a lot of work, technology and science. Even though there are billions of users of stainless steel items around the world, there are very few people (relatively) who know what goes into making a stainless steel product from scratch. The manufacturing process of a stainless steel product is indeed fascinating and it gives you an insight into how far our ability to craft materials has evolved since the early days of the Industrial Revolution. Here are the six most important steps in the manufacturing process of a stainless steel product:
1) Melting and Casting
The raw materials that constitute a stainless steel item are placed together and melted in a giant electric furnace. Intense heat is applied rigorously for a period of 8 to 12 hours during this step. Once the melting is complete, the molten steel is cast (moulded) into desired semi-finished forms. Some of the most common forms or shapes include slabs, blooms (rectangular shapes), billets (these could either be round or square), rods and tube rounds.
In the second stage, the semi-finished steel shapes undergo a series of forming operations. For instance, the stainless steel is hot rolled (heated and passed through enormous rolls). The blooms and billets mentioned above are converted to bar and wire. The slabs on the other hand are formed into plates, strips or sheets. It is very common to turn semi-finished steel shapes into bars, as it is the most versatile stainless steel form. The reason why it is versatile is because it comes in all grades and sizes. You have round, squared, octagonal and hexagonal bars, each suitable for a different type of application.
3) Heat Treatment
Up next we have the heat treatment. As the name clearly suggests, the various stainless steel forms undergo a thorough annealing process during this step. Annealing is another name for heat treatment where the stainless steel is heated and cooled in a controlled environment. The purpose of this heat treatment is to relieve the pent up stress inside the stainless steel and soften the material to make it more suitable for a wide variety of applications. The people in charge of carrying out the annealing process have to be very careful about control the conditions as even the slightest of changes in the temperature, pressure, duration or cooling rate could result in a faulty product.
During the annealing process, a certain amount of scale appears on the surface of the stainless steel. This scale can be removed using a number of different processes that are collectively known as descaling. Pickling is one of the more common methods of carrying out the descaling process.
The semi-finished, heat treated and descaled stainless steel forms are cut into specific shapes in this step. Mechanical cutting is performed with the aid of guillotine knives, blanking, nibbling and high speed blades.
Finishing is applied to help the stainless steel product achieve its signature aesthetically appealing appearance. Finishes are also needed to make the stainless steel product smooth and easier to clean, which is a top requirement in sanitary applications.