
Wire marks on the paper surface — causes ranked by likelihood:
Binder knuckle protrusion — Most common with standard triple-layer fabrics. The binder yarns connecting top and bottom layers protrude into the paper side. Solution: upgrade to SSB (Sheet Support Binder) design.
Fabric tension too low — Increase tension within the 4-8 kN/m range.
Mesh too coarse for the basis weight being produced.
Excessive vacuum — Reduce vacuum levels to the minimum required for adequate drainage.
Stock freeness too high — Adjust refining to reduce freeness.
Diagnostic tip: Map the mark pattern. Regular spacing matching weave pattern = fabric-related issue.
This answer is based on PAPTEX's expertise in Forming Fabric. PAPTEX provides engineered fabric solutions to 200+ paper mills worldwide.
Last updated: July 2026