Tape cross profile

Metal strip produced by cold or hot rolling does not have a constant thickness over the strip width due to the roll bending under load. The characteristic cross profile of a metal strip can be described by the following parameters:

• The profile is the elevation of the middle of the strip compared to the edges. ${\displaystyle C_{40}=h_{m}-{\frac {h_{A}+h_{B}}{2}}}$
• The wedge is the difference in thickness on both belt edges. ${\displaystyle K_{40}=h_{A}-h_{b}}$
• The edge sharpening is the progressive edge drop at the edges, which is caused by the transverse flow at the strip edges and the reduced roll flattening. ${\displaystyle W=h_{100}-h_{15}}$

The numbers in the index indicate the distance in millimeters from the belt edge. Usually 40 mm is used for the profile and the wedge. There is no generally applicable convention for sharpening edges.

The following options are available for influencing the cross-section:

• The use of backup rolls , e.g. B. in four-high, six-high or 20-roll arrangement.
• The bending of the rolls due to forces acting on the roll neck. Either the work roll or the support roll can be bent.
• The crowning of the rollers.
• The axial displacement of specially shaped rollers against each other, e.g. B. in CVC, HC or "smart crown" form.
• The interlocking of the rollers against each other.
• The selective support of the backup or work rolls.
• Influencing the thermal crowning through width-dependent cooling.
• Use of rollers with variable crown.