A tissue mill in Türkiye reached out to us with a persistent problem: their crescent former running ~1,400 m/min on 100% recycled pulp (ONP/OMG blend) had unstable Yankee dryer coating, 3–4 web breaks per shift, and doctor blades lasting only 3–4 days. Machine efficiency had dropped below 82%. Below is the key technical consultation.
Coating Instability
Q:The Yankee coating swings between too thick (blade chatters) and too thin (web won't stick, sheet flutter and breaks). We're breaking 3–4 times per shift. What's the root cause?
A:This is a coating balance problem - very common with recycled fiber tissue machines. Recycled pulp brings variable fiber quality, filler content, and contaminants (stickies, wax, adhesives from old magazines and office waste) into the white water system. These all interfere with how the adhesive coating forms on the Yankee surface. If your current adhesive isn't crosslinking consistently at Yankee operating temperature, the coating alternates between too soft (builds up, blade chatter) and too thin (poor adhesion, flutter, breaks). Stickies are thermoplastic - at Yankee surface temperatures they soften, embed into the coating, and create soft spots the blade digs into or hard spots that cause chatter. We recommend pairing PR-09 Cylinder Adhesive Agent with PR-02 Stickies Control Agent upstream to address both problems at once.
Why PR-09
Q:Our previous adhesive is also polyamide-based. Why would PR-09 be different?
A:Same base chemistry doesn't mean same performance. A cylinder adhesive agent's effectiveness depends on the polyamide's molecular weight distribution, its crosslinking kinetics at the actual Yankee surface temperature (150–200°C), and the protective additive package. PR-09 crosslinks at controlled density to achieve "moderate adhesion" - firm enough for creping, but not so rigid that the blade can't clean it. Its additive package helps the coating resist disruption from stickies and soluble contaminants in recycled pulp. A generic polyamide without these additives forms a coating that's vulnerable to contamination, softening, and uneven wear - exactly the instability you're seeing. PR-09 is applied through an online dilution spray system directly onto the Yankee surface, paired with a release agent (PR-07 or PR-08) in a controlled ratio. Starting dosage: 80–150 mg/m² (dry) for adhesive, with release agent at 10–30% of adhesive dosage by dry weight.
Adhesive & Release Ratio
Q:We've been adjusting adhesive and release agent independently. How should the two work together?
A:They're not independent - they're a paired system controlling the adhesion-release balance. Too much adhesive relative to release agent: web sticks too hard, coating builds up, blade wear accelerates, breaks increase. Too much release agent: coating becomes too slippery, web doesn't grip, creping quality drops, softness suffers. With PR-09 and our release agents, we help each mill establish a baseline ratio for their machine speed, pulp type, and paper grade. The goal is a coating that renews itself at a stable rate - old coating removed by the blade, new coating formed by the spray - without wild swings. Once you find the right ratio, keep it stable. Don't chase the coating by constantly adjusting.
Expected Results
Q:What results can we expect, and how soon?
A:Yankee coating replacement takes a transition period. After 6–12 hours at correct dosage and ratio, the old coating gradually replaces and the new coating stabilizes. Full optimization typically takes 24–48 hours. PR-09 works across all tissue pulp furnish types - recycled, blended, or virgin. When changing pulp blend, adjust the adhesive-release ratio accordingly (virgin pulp typically needs slightly less adhesive due to cleaner fiber surface).
Typical Results (Recycled Pulp Tissue Machine, ~1,400 m/min)
Web breaks: 3–4/shift → fewer than 1/shift
Doctor blade life: 3–4 days → 8–10 days
Machine efficiency: ~82% → 90%+
Creping uniformity and softness index significantly improved
Yankee coating thickness maintained stably, minimal manual intervention
If your mill is experiencing similar creping instability, excessive blade wear, or coating control difficulties, our technical team is available to review your process conditions and recommend a tailored solution.
