Shri Sivaayam Traders

Special Features:

• Low carbon content and made from fully killed steel.
• Higher yield strength, Ultimate tensile strength and higher percentage elongation when compared to cold twisted bars of same grade.
• Easy bendability, weldability and excellent ductility ensures economy and safety of use. o In-built ability to resist loss of strength at higher temperature.
• Require less energy for bending and re-bending along with superior reverse bending properties. o Can be butt welded or lap-welded. o Use of Fe-500 grade results in saving more than 15% in steel consumption when compared to cold twisted bars.
• Higher corrosion resistance and seismic resistance compared to CTD.
• Ideally suited for any type of concrete structure.
• Packing : Bare, in strapped bundles / piles weighing 7 to 8 metric tonnes approximately.
•  Invoicing : As per actual weight. 
• Quantity & Shipment: On mutually agreed terms

Quenching and Self Tempering (QST) imparts a composite micro structure ranging from a strong, tough, tempered martensite in the surface layer to a refined, tough, ductile ferrite-pearlite in the core with a intermediate structure in between. Superior rib design for excellent bonding with cement. Mean Projected Area much more than the specified values of the IS1786 standard.

Advantages ..of TMT (QST) Rebars of VSP Combination of high strength and high ductility VIZAG TMT bars have rare combination of high strength with excellent ductility. The tensile to yield strength ratios are always greater than 1.12. In normal bars, the increase in the yield strength of the bars is accompanied by the loss of percent elongation. But in the case of VIZAG TMT bars this loss is negligible and the percent elongation values are much higher than normally specified in various International Standards. In Fe 500D grade rebars the UTS/YS ratio values are maintained always at more than 1.15. Resistance to ageing The tests carried out on the VIZAG TMT bars, indicate that no significant change of strength as a function of time occurs which could affect the usefulness of these bars. Superior corrosion resistance The absence of Eutectoid Carbides and pearlite colonies in VIZAG TMT , absence of stresses because of tempering, presence of martensitic layer at the outside surface and formation of adherent scale film due to water quenching during rolling are the reasons for better corrosion resistance properties of these reinforcement bars.

Excellent bendability and workability The tough outer skin and the ductile core of the VIZAG TMT bars result in excellent bendability. This coupled with a high resistance to low temperature brittle fracture, allows these bars to be bent, without fear of failure around small diameter mandrels. In the reverse bend test, these bars also show good results. In the construction site, situation arises where bars bent are left for a period in the bent condition and then reverse bent. During period between the first bend and the reverse bend the bars may strain age. The loss of ductility due to strain ageing and due to strain imposed from the first bend may cause failure during rebending operations, if the bars are not sufficiently ductile. Test results have shown that VIZAG TMT bars have withstood successfully the bending, straightening and rebending tests after ageing. The bend tests carried out at VSP have shown that these bars could be bent even around smallest dia mandrel without causing any cracking

The only plant to adapt this technology (QST) for production of rebars from the design stage. Hence, the total extent of the superior technology could be harnessed. 120 metres length of the cooling bed available for self tempering which no other mill in India can match is the testimony for this.