Por: adel sheikhhosseiniesfahani (CHODANSAZAN(CSMETAL) CO), babak nazari (CHODANSAZAN(CSMETAL) CO), hosseini zakerinia (CHODANSAZAN(CSMETAL) co)
Resumo:
Cast iron rolls are defined as nodular irons or Nihard irons. The nodular irons used primarily in bar, rod and structural mills, may have either a pearlitic or acicular matrix and may be either statically or centrifugally cast. Some low alloyed irons are a type of Accicular cast iron rolls because of it has constitutes a much higher production tonnage. These rolls always double poured, and using centrifugal casting methods, even though it was statically cast for many years. AC+ and ACA Tech are high performance, centrifugal cast, double poured (AC duplex) work rolls. Acicular iron rolls for bar, rod and structural applications can have a hardness of 55 to 76 HSc. Extreme care in the foundry must be exercised to attain a hardness greater than 72 HSc This paper describes the principle of the AC+ and ACA-Tech rolls concept and its wide range of usability. The AC+ and ACA-Tech concept provides a solution for rod and bar mills to increase performance and output, even under harsh rolling conditions. The main focus is highly loaded mill stands that require both high wear resistance up to 30-40 % and increasing the resistance against thermal fatigue and crack propagation in dog bone, slitter and Finishing stand with the minimum hardness drop in depth and performance