R2R Operational Insights: Effective Dancers in Web Handling

Pivoting or sliding dancers are important dynamic parts of a web line and typically provide one or more of the following functions:

1. Apply tension to the web line. Using open or closed loop actuation, typically pneumatic, dancers can set the tension in a tension zone.
2. Any speed mismatch between upstream and downstream results in the change in the dancer position which can be sensed and used in the feedback control such as unwinding and rewinding.
3. The inherent web storage capacity of the dancer enables them to act as dampening elements to lessen the effect of disturbances

When properly designed and tuned, dancers help prevent tension spikes, reduce the risk of web breaks, and ensure smooth, continuous operation. However, poor configuration or inadequate control can lead to instability, excessive tension variation, and quality issues.

MapleSim’s web handling simulation tool enables engineers to:

• Model both passive and active dancer mechanisms, including pneumatic actuation, friction, gravity, and inertia.
• Analyze critical performance variables, such as web tension across spans, span length variations, and roller dynamics
• Evaluate design and control strategies virtually, reducing the risk of costly trial-and-errors or to understand and remedy performance issues.