Ten Mikron M9103's Play a Maxi-role in Mini-Mill's Product Quality! Arkansas.  In the last 20 years, mini-mills have largely replaced the integrated steel mill of the past century in the USA.  Electric melting, using recycled scrap metal rather than blast furnace iron, reduced pollution to manageable limits, making the mini-mill a more welcome member of many working communities.  The continuous caster is the heart of the mini-mill concept.  Today, mini-mills can be found throughout the USA and the industrialized world, and Nucor-Yamato’s plant in Arkansas is a typical example.   The plant produces a wide selection of structural shapes; among them “I” and “H” section beams.  Many of these are utilized in building and bridge construction in earthquake-prone areas of the world, and must comply with a stringent ASTME standard.   Nucor-Yamato’s Roll Mill Engineer states that Mikron’s M9103’s measurements are vital in meeting this standard.   Instructive photographs and diagrams of the plant can be found at www.nucoryamato.com   The Application   Historically, conventional single and two color thermometers have been applied to the caster strands, and the rolling mill, but are limited to point measurements that do not represent the “whole picture.”  Mikron’s unique Pyrovision M9103 has the essential feature of presenting a thermal picture in real-time, visually displaying critical temperature profiles of the caster strand, slab or the beam as it is being rolled, and also provides multiple analog outputs for control.       M9103 Pyrovision monitoring steel slab in a rolling mill.   At Nucor-Yamato, an M9103 is positioned at either side of the beam, aimed at the juncture of the web.  Water sprays, controlled by the analog outputs, are set to maintain uniform temperatures on either side of the beam.  The thermal image produced by the Pyrovision is an essential aid in the correct positioning of the water sprays. The temperature data acquired is paired, post process, with a “Charpy” test that determines the tensile and shear strength of the beam and compliance with the standard.   The M9103 has an important advantage over other thermal imagers in this context in that it measures in a narrow spectral band, close to the near infrared, significantly reducing errors attributable to surface emissivity variations typical of hot steel rolling.  Image “blooming” due to hot-spots, which is typical of other thermal imagers, is also eliminated.  To date Nucor-Yamato & Nucor Steel have purchased 10 Model M9103’s for rolling I & H beams and for temperature verification on Nucor’s strand casting operation to maintain product quality.   Model Number: M9103 Representative: HOLAN Engineering Tel:   870 862-5869 Fax:  870 863-0043 E Mail:  mholan@holanengineering.com Website:  www.holanengineering.com