The material properties of substrates such as paperboard are
normally measured under laboratory conditions but their physico-mechanical properties are likely to change during a press-
forming process. A measurement device of has therefore been developed to obtain real-time data of paperboard tray production and a new insight into phenomena related to press
forming and tool-substrate interaction. An existing mould set was modified for measurement of the
forming force by replacing the male mould with a mould that included a set of force sensors. Detection of defects such as ruptures require the use of multiple force sensors that make it possible to obtain more detailed measurement data.
To validate the performance of the device, a number of solid bleached paperboard (SBB) materials were selected to represent different kinds of coated paperboard structures in order to obtain a comprehensive general view of the phenomena occurring in the tray-pressing process. The friction coefficients of the test materials were measured by two different methods Force values obtained with the measurement device were used to calculate the friction coefficients and these were also obtained by a standard laboratory test method. The measurement device was also utilized to detect rupturing during the forming of the paperboard trays.
