Inline Breaker Bar Geometry Optimization and Reverse-Side Fluid Dampening Dynamics
Breaker bar geometry and reverse fluid dampening control film lamination curl by balancing plastic yield strain and z-direction substrate moisture gradients.
Rotor Spray Metering
Liquid Application
Centrifugal force generated by a spinning perforated cylinder distributes fine droplets of liquid across a moving web of paper or board. This non-contact method of coating or moisturizing relies on rotor spray metering to ensure a uniform film thickness. A series of rotating discs or a single rotor flings the liquid through a slot toward the substrate.
It allows for the application of very low moisture additions that would be difficult to control with traditional roller coaters.
Volume Control
Flow rates are managed by adjusting the speed of the rotor or the pressure of the fluid supply. Because rotor spray metering does not involve a nip, it avoids the hydraulic pressure that can push liquids too deep into a porous sheet. This makes it ideal for applying surface sizes or anti-static agents.
The precision of the spray pattern ensures that the edges of the web receive the same treatment as the center, which is necessary for maintaining a stable moisture profile across the entire roll. This uniformity prevents the development of wet streaks that cause wrinkles during winding.
System Maintenance
Accumulation of dried chemicals on the rotor can disrupt the spray pattern and lead to spotting on the paper. Regular cleaning cycles and the use of filtered liquids prevent nozzle clogging. The enclosure around the rotors must also be maintained to contain the mist.
This setup protects the surrounding machinery from corrosion.