Method for determination of an irreversible stretch and of a dynamic modulus of elasticity

A method for determination of an irreversible stretch and of a dynamic modulus of elasticity from a paper web for control of a papermaking process, wherein the method comprising the steps of

• measuring an on-line cross-direction tension profile, of the paper web (W) at two or more different tension levels,
• developing a fitted curve to the number of points of tension measurement carried out at each location of measurement in the cross direction of the paper web (W) of said adjusting step said curve describing local paper web tension as a function of relative stretch,
• determining an irreversible stretch (ε0) from each fitted curve, and
• determining a dynamic modulus of elasticity (E) from each fitted curve,
• wherein the determined values and profiles of irreversible stretch (ε0) and dynamic modulus of elasticity (E) are used for the control of the papermaking process;
• and
• wherein the control of the papermaking process is carried out as on-line feedback control by means of an automation system so that set values:
• or certain target areas or target values are assigned to said levels and/or profiles of irreversible stretch (ε0) and dynamic modulus of elasticity.