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The Importance of the Correct Bending Method and Choosing the Proper Mandrel Size for Rebar Bending

In the world of construction, the strength and durability of a structure are paramount. This is where the quality of materials and the precision in their handling come into play. Among these materials, TMT bars are the backbone of modern structures, providing the necessary tensile strength and flexibility. In this blog, we will delve into the significance of employing the correct bending method and selecting the appropriate mandrel size for rebar bending, with a focus on the features of AMBA Shakti SD TMT Bars and AMBA Shakti Flexion TMT Bars.

Understanding the Role of TMT Bars

TMT bars, or Thermo-Mechanically Treated bars, are widely used in construction due to their superior properties. They are known for their high yield strength, ductility, and earthquake resistance. The process of bending these bars is critical; it must be done correctly to maintain the integrity of the bar's properties. This is where the expertise of AMBA Shakti comes into the picture.

The Correct Bending Method

Bending TMT bars requires precision. A proper bending method ensures that the bars retain their super ductile nature, which is essential for earthquake-resistant structures. AMBA Shakti SD TMT Bars are manufactured with no twist straight mill rolling, which produces bars with no distortion, ensuring uniformity and better bonding with cement. This is further enhanced by CNC notching, which contributes to the uniformity in steel.

When bending these bars, using the right mandrel size is crucial. The mandrel size determines the inner diameter of the bend, and using an incorrect size can lead to cracks or compromise the structural integrity of the bar. The controlled raw material and high production standards of AMBA Shakti ensure that when bent correctly, the bars will perform optimally in any construction.

Choosing the Proper Mandrel Size

The mandrel size must match the specifications of the TMT bar being used. For AMBA Shakti SD TMT Bars, which are produced with high pass life HSS rolls for a good finish, the selection of the mandrel size is integral to maintaining the bar's finish and properties post-bending. The full automation of the mill ensures better quality control, which translates to consistent performance during and after bending.

Features of AMBA Shakti SD TMT & AMBA Shakti Flexion TMT Bars

Both AMBA Shakti SD TMT Bars and AMBA Shakti Flexion TMT Bars boast features that make them stand out in the construction industry. They are produced using Thermax® Patented Technology, ensuring high quality at a lower price—approximately 20% savings compared to local quality steel. The use of a sand filtration plant for cleaner water in the TMT quenching process enhances the finish of steel rebars and improves roll life.

Moreover, AMBA Shakti Flexion TMT Bars are designed to compete with primary steel manufacturers, offering cost benefits passed on from the savings on overheads of a smaller organization. The material is produced through the Ladle Refining Furnace (LRF) route, which refines the steel, making it purer and removing tramp elements detrimental to quality. This makes Flexion material suitable for complex and critical structures such as high-rise buildings, dams, airports, and megastructures.


The correct bending method and the choice of the proper mandrel size are critical factors in the use of TMT bars for construction. With AMBA Shakti SD TMT Bars and AMBA Shakti Flexion TMT Bars, you get the assurance of quality, durability, and cost-effectiveness. These bars not only meet the highest standards but also provide the flexibility and strength required for today's architectural marvels. When it comes to building the future, choosing the right materials and methods is not just a choice—it's a necessity.



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