Constructing homes, buildings, dams, bridges, and other architectures requires considerable effort and planning. Choosing the framework for these constructions is a delicate decision that requires scrutinizing minuscule details of products so that it brings sustainability. Selecting the best TMT bars from all the available alternatives is one such decision where engineers cannot afford to compromise on quality. This article discusses various factors and aspects of TMT bars to help engineers make the right choice. Procuring the best TMT bars from TMT steel suppliers in Kolkata often becomes challenging for engineers. It’s difficult to choose one from all the available alternatives. Here you will find the necessary guidance and information to make it easier for engineers to procure pure TMT bars from an array of similar products.
What are TMT Bars?
TMT bars are considered key components in developing structures of buildings, bridges, dams, and other constructions. It is a steel rod that is developed through thermomechanical treatment. While manufacturing the bars from iron, various twisting and turning occur, increasing the bar’s internal strength. Manufacturing the bars is responsible for their key characteristics, making them indispensable in construction projects. Before knowing its key characteristics, it is important to know the bar’s manufacturing process. It will help to choose the pure TMT bars while purchasing from TMT bars suppliers in Kolkata.
TMT bars are developed based on a process of three key stages. These three stages are discussed below.
Developing Molten Iron
The iron ore, coal, and fluxes such as limestone and dolomite are collected from the respective area. These materials are mixed and stacked in a proportionate ratio. The iron ore fines are agglomerated in sinters and pellets to increase the iron content in the mixture. This mixture is injected into the top of the blast furnace. The high heat of the blast furnace reduces the mixture into a molten form collected from the blast furnace’s base. The mixed impurities form a liquid slag and float above the molted part.
Developing Steel and Casting
The collected molten iron is put in the basic oxygen furnace. In this furnace, the iron is heated at high temperatures, close to 900 degrees centigrade. The system blows oxygen into the heated molten iron. The oxygen combined with carbon produces carbon-di-oxide. The process transforms the molten iron into steel. The steel is then subjected to Ladle-heating in Ladle Heating Furnace to make it desulphurized and dephosphorized. This process helps to degasify other inert gasses present in the ladle. After this, the molten metal is put in a casting machine to produce billets.
Hot Rolling and Thermomechanical Treatment
This stage is operated through three substages: quenching, self-tempering, and atmospheric cooling. In the quenching process, the heated steel casting is processed through different types of heat treatments and cooled through water spray in a quenching box. This process is followed to harden the outer layer of the TMT bars. In the next stage, the TMT bar is allowed to cool itself. The heated inner core transmits the heat to the outer layer. It causes the outer martensitic layer to turn into a tempered martensitic layer. The core structure remains austenitic. The bars are subjected to atmospheric cooling on a special cooling bed in the next stage. At this stage, the austenitic core turns into a ductile ferrite-pearlite structure. It results in a harder outer layer and a softer inner core.
Why are TMT Bars in Demand?
In India, the steel industry plays a pivotal role in supporting the progress of the real estate and construction sectors. Today, modern India considers the high-end infrastructure reflects the nation’s progress. Here, steel plays a key role. But, when it comes to the concern for constructing schools, bridges, dams, residential buildings, and other architecture, TMT bars cannot be avoided.
The advancement of technology has given us different grades of TMT bars, such as Fe-415, Fe-500, Fe-500D, Fe-550D, and Fe-600. Fe is the symbolic representation of iron and D represents ductility. The TMT bars are available in different diameters, including 8mm, 10mm, 12mm, 16mm, 20mm, 25mm, 28mm and 32mm. The standard length of TMT bar is 12 meters.
The TMT bars have a carbon content of 0.2%. It makes the bars highly weldable. It can be added with other bars through the normal welding process. It helps engineers to construct modern architecture without any hassle. Apart from this, the harder outer layer and softer inner core make the TMT bars highly flexible. This ductile nature of the TMT bars makes them desirable among engineers and TMT bars suppliers. The corrosion-resistant nature of the TMT bars ensures that the bars will help to make the buildings and constructions sustainable. These are why construction engineers and TMT bar suppliers demand high-quality pure TMT bars in Kolkata.
What are The Key Properties of TMT Bars?
The core properties of TMT bars make them desirable among civil engineers and TMT bars suppliers. Due to its properties, it has become easier to construct buildings, dams, bridges, and others in earthquake-prone areas. It has also become easier to offer sustainability to construction in humid areas or water-prone zones. Its quality is considered with high regard. The critical properties of the TMT bars are discussed below.
Chemical Properties
Maan TMT offers TMT bars of grade Fe-415, Fe-500, Fe-500D, Fe-550, Fe-550D, and Fe-600. The company ensures that the carbon content in the TMT remains much lower than the ISO standard. It helps to make the bars ductile, flexible, bendable, weldable, and corrosion-resistant. It offers one of the pure TMT bars available in Kolkata. The TMT bars suppliers prefer to choose Maan TMT bars as their phosphorus and sulfur content stays much lower than the benchmark mentioned in the ISO standard. The pure TMT bars are developed adhering to the ISO standard IS 1786. The chemical proportion of different materials in TMT bars maintained in Maan TMT bars is represented below.
| Chemicals | Maximum Percentage | |||||
| Fe 415 | Fe 500 | Fe 500D | Fe 550 | Fe 550D | Fe 600 | |
| Carbon | 0.30 | 0.30 | 0.25 | 0.30 | 0.25 | 0.30 |
| Sulphur | 0.06 | 0.055 | 0.04 | 0.55 | 0.04 | 0.04 |
| Phosphorus | 0.06 | 0.055 | 0.04 | 0.50 | 0.04 | 0.04 |
| Sulphur and Phosphorus | 0.11 | 0.105 | 0.075 | 0.100 | 0.075 | 0.075 |
Mechanical Properties
Maan TMT maintains the yield stress, elongation, and TS/YS ratio as per the norms mentioned in the IS: 1786 standard. Therefore in Fe-415 grade, the pure TMT bars in Kolkata maintain the maximum yield stress of 540 N/mm2. In the case of Fe-500 grade TMT bars, the yield stress of 625 N/mm2 is followed. The aim of the TMT bars manufacturer remains to ensure the product is sturdy, efficient, sustainable, and effective. Other mechanical properties followed in different grades of TMT bars have been mentioned below.
| Property | Fe-415 | Fe-500 | Fe-500D | Fe-550 | Fe-550D | Fe-600 |
| Yield Strength | 540 | 500 | 625 | 550 | 550 | 600 |
| TS/YS ratio | ≥ 1.10, but TS not less than 485.0 N/mm2 | ≥ 1.08, but TS not less than 545.0 N/mm2 | 1.25 | ≥ 1.06, but TS not less than 585 N/mm2 | ≥ 1.08, but TS not less than 600.0 N/mm2 | ≥ 1.06, but TS not less than 660 N/mm2 |
| Elongation Percentage
(Min) |
20 | 12 | 18 | 10 | 14.5 | 10 |
| Elongation Percentage
(Max) |
10 | – | 8 | – | 5 | – |
How to Select The Best TMT Bars
In Kolkata, TMT steel suppliers source TMT bars from different manufacturers. Choosing the best TMT bars according to the construction requirement is a key prerequisite. However, engineers find it challenging to choose pure TMT bars from available alternatives. This section identifies key factors to consider while selecting TMT bars.
1. Know What You Demand
Before selecting the pure TMT bars from one of Kolkata’s key TMT steel suppliers, you must know your requirements. The TMT bars are available in different grades. Different grades are effective for different purposes. The Fe-415 TMT bars are effective for constructing residential buildings and small-scale projects. Fe-500 grade TMT bars are effective for residential, commercial, multi-store, and high-rise projects. The Fe-500 grade TMT bars have higher tensile stress and yield strength than the Fe-415 grade TMT bars.
If you are building projects in a water-prone humid area, you would require Fe-550 grade TMT bars. These TMT bars have a high degree of corrosion resistance property which make the construction of dams and bridges in marine and coastal areas highly sustainable. Fe-600 pure TMT bars are the strongest among all the TMT bars offered by TMT bars suppliers. These TMT bars are effective for heavy-duty industrial projects, metro projects, expressways, towers, and marine facilities. The TMT bars have the highest yield strength, tensile stress, durability, and corrosion-resistant properties. While procuring the pure TMT bars from TMT bars suppliers, you should identify the grade you need based on the above characteristics of the TMT bars.
2. Explore the Brands Available
The TMT steel bars suppliers in Kolkata will offer you different TMT steel bars from different manufacturers. You must choose the right brand according to cost, quality, quantity, certification, and other aspects. Maan TMT bars is one of Kolkata’s premier TMT bar manufacturing companies. It offers pure TMT bars developed adhering to IS: 1786 certification. You will get this brand at an affordable price. If you are interested in knowing more about the company and evaluating the TMT steel bars manufacturing process, you can visit the company’s factory in Kolkata.
3. Evaluate the Properties
To select pure TMT bars from TMT bars suppliers in Kolkata, you must evaluate the properties of the TMT bars through direct evaluation. Maan TMT offers pure TMT bars with rib structure, high bendability, superior welding capability, better ductility, high flexibility, and superior corrosion-resistant property. It often becomes difficult to ensure that certain properties, such as corrosion resistance or weldability, follow industry standards. In those cases, you need to check if the TMT bars manufacturing company adheres to the ISO standard while manufacturing the TMT bars.
4. Evaluate the Certification
Pure TMT bars come with proper certification. While procuring the best TMT bars from TMT bars suppliers, you must identify if the product is offered with ISO certification. Maan TMT follows the IS:1786 industry standard to ensure the quality and properties of TMT bars manufactured. If the TMT bars suppliers fail to present the certification documents of the TMT bars, we suggest refraining from purchasing the product. You should not compromise on the quality and authenticity of the TMT bars to ensure better safety, security, and sustainability of construction projects. That is why certification plays a significant role in identifying if you are buying the best TMT bars from TMT steel bars suppliers in Kolkata.
5. Evaluate the Cost of TMT Bars
Cost plays a key role in selecting the best TMT bars from TMT steel bars suppliers in Kolkata. You would procure a large quantity of TMT bars to support the need of the construction project. Therefore, the TMT bars you choose must be affordable to make the construction project economically feasible. However, you cannot compromise on the quality. Maan TMT offers high-quality, affordable TMT bars in Kolkata, which you can easily source from reputed TMT bars suppliers in Kolkata. The certified TMT bars offered by Maan TMT ensure that construction projects last long without developing any risk of breakage and other potential hazards.
You must consider these few aspects while procuring the best quality TMT bars. However, to become 100 percent sure about the quality of TMT bars, you must evaluate their reputation before making any final choice. Online reviews about the products and feedback from different influencers in the industry are two key sources to collect information about the quality and reputation of the brand. However, you should not overlook the above factors to come to a better conclusion. When you can access all the necessary information, you will be able to make the right judgment. Therefore, consult with the company representatives and TMT bars suppliers to know which TMT bars will be a perfect fit for your project in terms of cost, quality, and quantity.