Using rollers with increased barrel length in four-high mills

Increase in barrel length of the working rollers from 3100 to 3400 mm is proposed in the 3000 mill, without change in barrel length of the supporting rollers (2980 mm) or in the structure of the cell. Calculations of the pressure between the rollers and the transverse thickness variation of the rolled metal when the barrel length of the working rollers is 3100 and 3400 mm shows that the maximum pressure between the rollers is increased by 6–8% for 3400-mm working rollers with rolled sheet of maximum width 3200 mm; the rolled material is concave. To obtain a convex cross section, the depth of the bevel of the edges of the supportingroller barrel is doubled. Increasing the length of the working rollers in the 3000 mill at PAO Mariupol’skii Metkombinat im. Il’icha permits the production of commercial sheet with a width up to 3000 mm.