The effect of viscoelasticity in web handling systems is examined by i
ntroducing a viscoelastic equation of state into a model for tension c
ontrol. Case studies and generalized results for a single open-span sy
stem and a double open-span system are presented to compare the result
s of the viscoelastic model to a model based on a purely elastic equat
ion of state. The results show only small differences in the tension b
ehavior for the single-span system. However, large differences in the
magnitude and reversal of the sign of the tension in the second span o
f a two-span system are seen for even small degrees of viscoelasticity
in the web material. The results clearly demonstrate that viscoelasti
city must be considered in modeling multispan web handling systems.