Compliant-gap

Compliant-gap metering is characterized by one or both gap walls, or their mountings, being deformable by forces developed in the flowing liquid. Those forces are pressure above all, but also viscous wall shear and, in certain nonlinear and many viscoelastic... 

Transfer application employs a compliant gap to apply most of an arriving pre-metered layer to substrate passing through the gap. The compliant element can be either a soft transfer roll (often called an applicator roll), a soft backing roll, or the web tensioned over a transfer roll. 

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