Piezoelectric Sensor Frequency Response Calibration for Folding Boxboard Converting
Piezoelectric sensor frequency response calibration prevents amplitude distortion during high speed creasing by matching amplifier cutoff to rule strike transients.
Dynamic Overshoot
Response Amplitude
Mechanical tension variation occurs when a moving web of paper experiences a sudden speed adjustment on a printing press or converting line. This dynamic overshoot describes the transient peak tension that exceeds the set-point value immediately following an acceleration or braking command. Controlling this peak is necessary to prevent web breaks during high-speed run-ups.
If the tension spike exceeds the tensile strength of the paper grade, the web will rupture, causing immediate line stoppage.
Web Behavior
Web handling systems on modern offset and flexographic presses must manage the inertia of large paper reels during rapid speed transitions. During start-up, the tension control system adjusts the brake force at the unwind stand to maintain a stable tension. However, the lag in sensor feedback and pneumatic brake response often results in a significant dynamic overshoot of tension before the system stabilizes.
This transient force is particularly hazardous for lightweight papers or recycled grades with lower tear resistance. Machine designers incorporate dancer rollers and feedback loops to absorb these transient energy surges and dampen the overshoot amplitude. Proper tuning of the press controllers minimizes the duration of the tension spike, reducing the risk of paper damage.
System Limit
Material elasticity defines the threshold at which these transient tension spikes cause permanent deformation or structural failure. Papers with high stretch capacity withstand greater tension peaks without rupturing. Conversely, brittle materials require more conservative press acceleration profiles to remain below the damage threshold.