TMT Technology

SK Super TMT’s superior quality Thermo Mechanically Treated (TMT) bars are manufactured using state-of-the-art German Technology, supervised by expert metallurgists and engineers. ISI grade steel billets are subjected to PLC controlled on-line Thermo-mechanical treatment; hot rolled in fully automated rolling mills equipped with computer controlled process monitoring devices to ensure uniform properties in each TMT bar. The superior technology ensures excellent dimensional tolerance and very good surface finish. SK Super TMT’s four stage Quenching processed premium TMT bars represent the new-generation superior quality, high strength steel TMT bars meeting international standards.

The four-stage process:

A high pressure water spray system rapidly quenches the hot bar leaving the final DC stand. During which, the surface of the steel bar is hardened to a depth most effective for each section through the formation of a martensitic rim, and a hot and austenitic core.

After quenching, the steel bar rests on a cooling bed. The hot core allows the heat from the core to flow up to the surface, causing the desired tempering of the outer martensitic layer into a structure called ‘tempered martensitic’. The core remains austenitic.

Brittle metal scales on the outer martensitic layer are removed as they may cause an uneven outer structure after atmosphere cooling. High pressure air compressors attached to the system release air at high pressure, enabling the removal of scales attached. At this stage, the steel bar attains uniform strength and a better metal structure.

The last stage of the process takes place on the cooling bed where the austenitic core is turned into a ductile ferrite pearlite structure. The final structure obtained consists of a combination of two layers – the strong outer layer and a ductile core which gives the bar super strength and high ductility.

The 4 stage process gives SK Super TMT bars high strength, greater yield & elongation, uniform micro structure, toughness, ductility and weldability. Their heightened rib pattern (X-core ribs) bonds perfectly with concrete. The ribs are designed in a unique pattern to provide greater depth and maximum spacing for close bonding with the concrete for longer, stronger robust structure.

Testing

At SK Super TMT, we make sure that every TMT Steel Bar we produce is tested for quality and strength, before it is packed and sent for sale. Our state-of-the-art manufacturing facility is equipped with a full-fledged testing laboratory, designed to carry out every necessary test that is important to determine the quality of steel produced for the market.

SK Super TMT’s testing methods include:

Universal Testing Machine (UTM):

Conducts a stress test on the steel bar, and gives readings of the proof test, tensile stress and elongation

Ring Test:

Tests the steel bars by dipping their end into an acid bath for a specific amount of time. When the end is removed, two circles are seen, showing the outer surface as a distinct layer from the inner core. This test confirms that the steel bar has been through the ‘Quenching Process’, and helps separate fake TMT from genuine SK TMT steel bars.

Spectrometer:

Determines the physical and chemical composition of the steel bars. Its real time presence gives the exact percentage of its 28 key elements within a timeframe of 10 seconds.