Floating Flange Roll

This design is predominantly used in production of large diameter (above 250mm Ø) pipes, especially in stainless steel material where roll markings and material pick up may be critical quality parameter. Marking and material pick up results from the extreme difference in surface speed between the root of the roll and higher contour of the outer flanges. The higher surface speed on OD of the roll try to pull the edges of the strip ahead of the center of the strip causing markings. To address this problem, the upper half part of the roll is made to rotate freely above lower half part of the roll which is keyed to the mill shaft. There are two options for floating flange design : A. Floating flange with bearings – Fig. I In this design flanges rotate on a pair of roller bearings. B. Bearing less floating flange - Fig. II This arrangement is similar to rotation of driven part on a bearing bush. Continuous lubrication is provided for smoother rotation of the outer part of the roll assembly. Different styles of rolls have their own advantages and limitations. Due to initial budget constraints, mill management generally decide on using solid rolls. However, better results may be achieved by adopting more than one style of tooling. For example, one may use split rolls in the driven fin and sizing sections and solid tooling on the rest of the mill.