Compressible 3M Mill Rolls -- tight contact for consistent
wringing, oiling, and de-oiling.
3M Mill Rolls are slightly compressible with a porous open
surface. With the compressible, sponge-like characteristic, the
rolls conform to the smallest variations in gauge thickness to
maintain consistent tight contact across the strip. This tight
contact helps assure exceptionally uniform wringing so strips
emerge drier from the rinse tank. In some cases, users have found
up to a 95 percent reduction in solution "carry through" compared
with conventional rubber rolls. The porous surface absorbs the
fluid's hydrodynamic forces to greatly reduce the chance of hydroplaning,
which can cause slippage.
Oiling and De-Oiling
With tight contact, 3M Mill Rolls meter and apply lubricants
consistently and uniformly. Operators can remove excess protectant
oils on incoming metal strip. This "de-oiling" helps reduce costs
and improve capabilities in the caustic cleaner.
The results of 3M Mill Rolls replacing rubber rolls in an
automotive stamping operation are shown below. With the more effective
wringing action of the 3M rolls, defects were reduced from
four per hundred stampings to approximately one per hundred.
(See Graph Below)
Broad Operational Pressure Range
3M Mill Rolls can be used within a wide range of pressures
and temperatures and still provide excellent wringing. Wringing
has been evaluated under a wide range of operating pressures.
Nip pressure as measured in pounds/linear inch of roll width (PLI)
is the key parameter.
Easy to Repair and Reuse
While 3M Mill Rolls resist cuts and gouges and are self-healing,
they still can be damaged by major irregularities in the strip
surface. Sharp edges from a break in the strip, for example, could
severely cut the roll.
Star Tool & Die can make repairs quickly, eliminating the need
to inventory large numbers of replacement rolls as spares. If
severe damage occurs, the damaged portion of the roll can be removed
from the shaft and repaired within a few hours.