Almost all high speed winders must employ a nip roller in contact with the outer surface of the winding roll to prevent air entrainment. The nip roller, which may or may not be covered with an elastomer, induces local dynamic pressures where it contacts the winding roll that travel at the surface velocity of the winding roll. After rolls are wound, they can witness additional surface contact pressure. Often, rolls are stored on flat surfaces and the dead weight of the roll induces contact pressure. In other cases, the roll maybe moved by a clamp truck that employs hydraulic pressure to clamp and lift the wound roll.
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