Thermo mechanically treated bars have brought about a revolution in construction due to its high yield strength, high ductility, high weldability and most importantly resistance to the corrosive and seismic forces of nature. Now responsible for all the critical architecture that you see around yourself, TMT Bars make the most impactful reinforcement steel bars to date that address every concern you have with regard to quality and reliability. This is only and only because of its unique manufacturing process- a long and detailed one where these rebars get imparted with a very distinct microstructure- the combination of a soft ferrite core along with a tough outer surface.
This blog explores each and every step of this critical manufacturing in detail which any reputed TMT bar company has to be a master at in order to translate their bars into embodiments of strength and safety for you all.
The following is a detailed breakdown of the manufacturing process of quality TMT rebars from the start right to the finished product:
Raw material selection is the first and a fundamental step in the creation of thermo mechanically bars. Iron ore, limestone, coal, and coke, are some of the best raw materials with a very low impurity count that good manufacturers must definitely be using to improve the strength, corrosion resistance and overall quality of TMT rebars. Composing on raw materials is dangerous. It can affect the structural integrity of the concerned building and risk major failures.
It is here that the aforementioned raw materials are processed through blast furnaces in extreme temperatures to result in what is known as molten steel. This molten steel for the purpose of refining is transferred to a ladle furnace to ensure certain processes such as deoxidation, desulfurization and more. Without proper steelmaking, the desired chemical and mechanical properties of thermo-mechanically treated bars cannot be achieved.
In this process, the steel billets go through temperatures ranging between 1200°C to 1250°C which leads to the reinforcement of the shape and size of the bar. After this, it goes through the rolling mills to attain its final form. This brings about the much-needed balance between strength and flexibility. It is here that the bars get imparted with their initial mechanical strength.
Heating is followed by quenching and self-tempering. It is the rapid cooling method that follows the intense heating process at high temperatures. It is what makes these TMT bars so unique. Water is passed through these hot-rolled bars to bring down the surface temperature. Thus, the surface gets cooled down while the core remains extremely hot, thereby imparting the thermomechanically treated bar with incredible strength, ductility and other mechanical properties.
After the process of tempering, the bars are left undisturbed, as the cooling process is natural and is done at room temperature. Shear cutters are used to shape the fibres into the lengths required.
The more stringent the quality control procedures are, the better the resulting bars are. Better quality control has a direct impact on the number of hallmarks, standards and certifications a rebar is geared up with. The more, the better-as they are a direct indicator of quality. Prominent and reliable manufacturers have detailed breakability, bend and rebend and chemical composition tests to ensure the best product to their customers.
Companies that are spread out with warehouses and distributorships all over the country have a better chance of giving you final products that have not undergone loss of quality or wastage during logistics and transportation. Also, you must know that the better the quality of TMT rebars, the less is the susceptibility to wear and tear and damages incurred during transportation. Thus, when it comes to transportation, established TMT bar companies are always the more reliable choice.
Read Also: The Role of Certifications and Standards in TMT Bars
SEL Tiger TMT, one of the biggest names in TMT bar construction in India has been gaining the trust of not just its customers but also its competitors for decades. SEL Tiger TMT certifies and confirms to renowned national and international standards. Some of the institutions that our TMT bar complies with are ISO, BIS, NABL, MS & CRS through IS 2830:2012. This is the direct result of acing every single aspect of manufacturing. Made with the finest materials including billets and ferroalloys, our certification is not just a one-time process. We emphasise the importance of continuous stringent and detailed manufacturing with the help of our expert customer support and guidance team to reinforce trust, reliability and quality from time to time.
Our steel bars are equipped with a special ribbed design for better bonding with cement. Not only that, we also provide advanced corrosion protection to safeguard your building from the harsh Indian climate full of corrosive forces. Other than that, our expert support post sales and our country-wide network make us a unique and stand-out TMT bar company in the subcontinent.
If every aspect of manufacturing is not perfected, then the structural integrity of the building is compromised. Not only can that cause depreciation in terms of reduction in aesthetic value but also potentially act as a threat to life and property.
The thumb rule here is to never compromise on quality. Cost efficiency can only be achieved if you choose to go for the enormous long-term benefits that high-quality TMT rebars provide. This means that going for a TMT bar with a cheaper price will besides incurring you heavy losses and expenses in the future also impact the safety of your close and loved ones.
About the Author: Bishan Mukherjee has been a quality control specialist when it comes to TMT bars for decades. His insights are backed by hands-on experience, facts and practicality. His writing is aimed to arm the readers with the correct knowledge so that going forward in construction that can make the decision that’s capable of meeting their unique needs.
