Goel Group

Manufacturing Process

Each GOEL TMT bar is put through Thermex® Process which gives it extra strength and ductility. GOEL TMT Rebars are hot rolled from billets and subjected to PLC controlled on-line Thermex QST System in three successive stages :

(A) Quenching :

Directly after leaving the last rolling mill stand the bar is passed through Thermex® cooling pipe where it is rapidly water quenched for suitable time depending on the size of the bar and the rolling speed. This hardens the surface of the bar to optimum depth by forming cooled martensite outer surface. However, the core remains hot and austenitic.

(B) 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 martensite layer into a structure called “Tempered Martensite”. The core still remains austenitic at this stage.

(C) Atmospheric Cooling :

This takes place on the cooling bed where the austenitic core is transformed into ductile ferrite-pearlite structure. Thus the final structure consists of an optimum combination of strong outer layer (tempered-martensite) with a ductile core (Ferrite-Pearlite). This gives GOEL TMT its unique combination of higher strength and ductility.