Process
 

Manufacturing Process Of National TMT Bars

Stage1

Our steel is produced through the virgin iron ore route. The direct reduced iron produced in rotary kilns is used as raw material in steel melting shops.

Stage1

The direct reduced iron is melted in electric induction furnaces which is further processed in LRF & AOD to produce steel of high cleanliness and homogeneous quality.

Stage1

The processed liquid steel is transferred to a continuous casting machine to produce billets.

Stage1

The billets are the raw material for TMT bars and are fed to a rolling mill.

Stage1

Quenching - The hot rolled bar leaving the final mill stand is rapidly quenched by a special water spray system – TEMPCORE (CRM-BELGIUM). This hardens the surface of the bar to a depth optimised for each section through the formation of a martensitic rim while the core remains hot and austenitic.

Stage1

Self Tempering – When the bar leaves the quenching box, the core remains hot compared to the surface, allowing heat to flow from the core to the surface, causing tempering of the outer martensitic layer into structure called ‘Tempered Martensite’. The core still remains austenitic at this stage.

Stage1

Atmospheric Cooling - This takes place on the cooling bed where the austenitic core is transformed into a ductile ferrite-pearlite structure. Thus the final structure consists of an optimum combination of a strong outer layer (Tempered Martensite) with a ductile core (Ferrite-Pearlite).

Stage1

The bar is then cut into lengths in multiples of 12 meters or as per customer’s requirement and bundled in an automatic bundling station.

Stage1

The bar is then cut into lengths in multiples of 12 meters or as per customer’s requirement and bundled in an automatic bundling station.

Certifications

SPSIL's commitment to quality is underlined by our ISO 9001:2015, ISO 14001:2015, and ISO 45001:2018 certifications,
ensuring international standards in all our products.

Awards