New Technology to Meet Challenges of High Quality Rebars--Danieli-QTB PLUS~(TM)

摘要

East and South-East Asia together produce 62 percent of world's rebar and consume nearly all. Much of the economic progress in this region is driven by large scale infrastructural development and constructional activities. With sustainable development at top of the agenda many steel producers are facing challenges to produce stronger and more durable rebars of superior quality at minimum waste, energy, and resource utilization - all at lower production cost, and better customer service. This poses significant challenge as much on additional operational discipline as on new technological innovation. DANIELI addresses this issue with its new 'QTB Plus' technology, that predicts and controls mechanical properties of Quenched & Tempered Bar (QTB) over length and across section in real time during actual processing. Better control over properties improve quality, enhance operational performance through reduction in downgrading and yield loss. DANIELI-QTB Plus is meant for estimation of Yield Strength, Tensile Strength, Hardness, and Elongation of the Thermo-Mechanically Treated (TMT) rebars produced in the Bar and Rod Mill through better process control. It uses a series of Metallurgical Models to predict final microstructure and properties. Use of the system help reduce testing of samples for customer order certification, and thereby reduce sampling and testing cost. Moreover, it improves delivery time, reduces inventory and its holding costs. The accuracy of prediction of the system is found to be ± 10-20 MPa for YS, and + - 10-25 MPa for UTS, depending on the size of the bar. DANIELI QTB Plus has been implemented last year in the Bar Mills of Riva at two locations - Verona (Italy), and Seville (Spain).