Page 48 - ITA Journal 3-2018

Technical Papers
SMS group GmbH
Benchmark plant for premium tube and bar grades
Immediately after austenitization, the material is evenly quenched in the SMS Quenching Shell® for ID and OD cooling, thus generating a highly homogene- ous microstructure.
tion takes place using the hybrid method with an induction and gas- red furnace. The products are then discharged rapidly and immediately enter the innova- tive OD/ID SMS QuenchingShell®. Quenching produces a consistent martensitic structure inside the steel. Thanks to their constant rotation and the arrangement of the nozzles, the products are cooled evenly which results in a highly homogeneous microstruc- ture. After cooling, the products can undergo further tempering in the line or be transported to the rst sampling saw for testing the material “as-quenched.”
Tempering is performed using the hybrid method, as well. First, the product is preheated by means of induction, and then it enters the gas- red tempering furnace. The combustion furnace has two sections: The front section con- tains direct heating chambers with high-velocity burners, and is followed by a section with indi- rect heating chambers. Special heat-resistant fans, arranged on the tempering furnace second part, ensure the recirculation of the heated air inside the furnace chambers.
TimkenSteel is very satis ed with the new AQTF (Advanced Quench-and-Temper Facility) from SMS group for the quench- ing and tempering as well as normalizing of tubes and bars.
The Advanced Quench-and- Temper Facility (AQTF) has been jointly developed by TimkenSteel Corporation and SMS group. It is suited for quenching and tempering as well as for normalizing of bars and tubes.
Special features of the tech- nology are hybrid heating (induction and combustion) and the SMS QuenchingShell®.
The outcome is homogene- ous treatment results and a uniform microstructure.
SMS group has supplied an AQTF (Advanced Quench-and-Temper Facility) to TimkenSteel Corpora- tion for its Gambrinus complex in Canton, Ohio. The exible AQTF is suited for quenching and temper- ing as well as for normalizing of bars and tubes. TimkenSteel and SMS group have jointly developed the AQTF concept, which stands out due to hybrid heating with a combination of induction and combustion parts as well as the SMS QuenchingShell® for exible and simultaneous quenching of outer and inner sides.
CONSTANT ROTATION
Throughout the whole process, the tubes or bars rotate around their own axes to ensure homogeneous treatment results and a consistent microstructure. Austenitic forma-
ITAtube Journal No3/October 2018
48