![]() It may be even up to 20 mm thick depending upon its application. The outer surface of the barrel is chilled (Fe3C) providing very high hardness. The composition is more or less similar to cast iron but its structure is different. The addition of Molybdenum increases the strength and heat resistance properties. These rolls are used for rolling flat products like sheets and plates and small sections. The chill surface is very hard and provides good finish. Below just a few relevant types are specified.Ĭhill Cast Iron: The roll casting is performed vertically with barrel in chill moulds. There is a wide range of cast iron rolls available in the market. ![]() Improved casting technology over the years also contributed to enhanced properties of Iron Base Cast Rolls. In order to increase the strength, finish quality, wear – and heat resistance, a number of alloying elements are currently added to the iron rolls. Many years ago, cast iron or chill cast iron rolls were the only types used. This type of rolls is used most times in rolling mills, mainly because they result in good finish and possess good wearing properties. Chromium content is available up to 7 – 9%. With unique grades unparalleled tonnages are achieved between regrinds. Special refined tool steels serve as the base for a range of long life high precision rolls for the Aluminium Rolling Mills. Forged and hardened rolls are also used as back-up rolls in 4 high mills although normally alloy cast steel rolls are used for back-up. These rolls are primarily used where they have to withstand high loads as in Blooming Mills or in Heavy Section Mills. However, because of the lower carbon content the hardness is low and more subject to wear than cast rolls. The structure of forged rolls is denser than cast steel rolls and therefore, are tougher and can absorb more load. Forged rolls contain less carbon compared to cast rolls because high carbon content would cause cracks during the forging process. Adamite ‘A’ is the softest but toughest and Adamite ‘E’ the hardest but least tough.Īll these rolls are cast, heat treated and machined and have nearly uniform hardness throughout the transverse cross section. Depending upon carbon content these Adamite rolls are classified as A, B, C, D or E. The most common rolls in this group are called ‘Adamite’ rolls. These rolls with small alloy contents are used in big sizing mills such as Blooming Mills. To get better wearing properties, molybdenum and chromium are added and nickel is introduced for imparting strength and resistance to fire cracking. The cheapest rolls in this group are plain carbon steel rolls. These cast steel mill rolls have qualities and grain structure like steel although the carbon content may be quite high (up to 2.5%). Steel Base Rolls (Cast or Forged) Cast steel rolls: Quality: ISO 9001, ISO 14.001 OHSAS 18.001įull inspection of rolls with all available testing equipment. Deep Freezing tunnels are also used.įinishing: Full range of CNC lathes, and grinders are used, totaling up to 50 units. ![]() Quenching by means of electric or sprays. Heat Treatment: 16 different furnaces, electric and gas heated are available. Melting: In order to be able to produce virtually all types and dimensions of rolls, we work with EAF, ESR, and Induction smelting equipment.įorging: Automated forging presses can process the heaviest plate mill back up rolls.Ĭasting: Cast Rolls are produced in vertical and horizontal spin casters, and static casters.
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