Two Drum Surface Slitter Rewinders

A surface slitter winder is a machine used to slit and wind flexible web materials (such as paper, plastic film, and foil) into smaller rolls. Unlike other slitting methods, the surface slitter winder uses a surface-driven winding mechanism, providing better control over the winding process and ensuring high-quality rolls with uniform tension.

he surface slitter winder works in the following steps:

• Unwinding: A large roll of material is unwound and passed through a set of rotating slitter knives that cut the web into narrower strips.

• Slitting: The web is slit into desired widths by rotary score knives or rotary shear knives.

• Winding: After slitting, the narrower strips are wound onto separate cores by the surface-driven mechanism, maintaining consistent tension across all rolls.

• Top Rider Roll: The rider roll is positioned above the wound roll and applies pressure to control web tension during winding. Its main function is to ensure uniform tension across the web, preventing defects like wrinkling, stretching, or improper roll build-up. By maintaining optimal contact with the material, it helps produce a consistent, high-quality roll. The top rider roll works alongside other winding mechanisms to evenly distribute tension and achieve a uniform roll structure.

• Precision: The surface-driven mechanism provides highly precise winding, ensuring uniform roll quality.

• Reduced tension variation: By maintaining consistent tension across the material, surface slitter winders reduce the risk of over- or under-tightening the wound rolls.

• Higher quality finished product: The precise tension control and winding lead to better quality rolls, which is crucial in industries where material integrity is vital (such as in packaging and printing).

• Improved production efficiency: These machines often feature automation and speed control systems, increasing throughput while reducing manual intervention.

Surface slitter winders typically use the following slitting methods:

• Shear slitting: Involves two circular blades moving in opposite directions, providing a clean cut with less pressure. It’s suitable for thicker or more rigid materials.

• Score slitting: Involves a blade that creates a score line on the material, which then splits along the score. This method is commonly used for materials that require a more controlled and less aggressive slit.

• Rotary Burst slitting: Uses rotating knives or blades to cut the web into narrower strips. This method is widely used for high-speed slitting of flexible materials.