Fabric Contamination & Stickies Build-up: The Hidden Driver Behind Drainage Loss and Fabric Performance Decline
- Snehes Dasgupta
- Apr 18
- 4 min read
In today’s paper machines—particularly with increasing dependence on recycled furnish—fabric contamination and stickies build-up have emerged as one of the most critical yet underestimated performance challenges. Deposits such as adhesives, latex, pitch, fillers, and fines gradually accumulate within the forming fabric structure. Over time, this accumulation restricts flow paths, reduces permeability, and disturbs drainage uniformity.
As highlighted in industry guidance from TAPPI / Paper360, maintaining fabric cleanliness is not a one-time activity but a continuous and engineered process essential for stable machine performance.
Section 1 — Perspective for Paper Makers
Contamination Directly Impacts Drainage Efficiency
The primary function of a forming fabric is to facilitate rapid and uniform water removal. However, as contaminants begin to occupy the void spaces within the fabric, the effective drainage channels shrink. This leads to reduced dewatering capacity, forcing more water to travel forward into the press section. The downstream impact is immediate—higher press loading, increased moisture after press, and elevated steam demand in the dryer section. In many cases, mills attempt to correct this through operational adjustments, while the root cause remains embedded within the fabric itself.
Stickies Create Localized Instability
Unlike general contamination, stickies introduce a more complex problem due to their adhesive nature. These materials not only deposit on yarn surfaces but also capture fines and fillers, forming localized clusters within the fabric. This results in uneven drainage zones across the machine width. Such non-uniformity often manifests as sheet defects, poor formation consistency, or unexplained wet streaks. Because these effects are localized, they are frequently misinterpreted as machine or headbox issues rather than fabric-related problems.
Cleaning Strategy Determines Performance Stability
One of the most important insights from current industry practices is that cleaning effectiveness is governed more by strategy than by intensity. Continuous cleaning systems, such as oscillating or traversing showers, are far more effective than intermittent high-intensity cleaning. Additionally, the selection of nozzle type, pressure, and chemical cleaning agents must align with the type of contamination present. An aggressive but poorly designed cleaning approach can damage the fabric, while an insufficient one allows contamination to build rapidly. The balance between these extremes defines long-term fabric performance.
Early Indicators Are Often Overlooked
Fabric contamination rarely appears suddenly; it develops progressively. Early warning signs such as gradual permeability reduction, increasing vacuum requirements, higher press moisture, or minor profile variations are often ignored until they escalate into larger operational issues. Monitoring these trends systematically allows for timely intervention, preventing both production losses and premature fabric replacement.
Section 2 — Perspective for Forming Fabric Manufacturers:
Designing for Contamination Resistance
Modern forming fabric design must go beyond mechanical strength and initial drainage performance. With increasing contamination challenges, resistance to deposit build-up has become equally important. This requires careful consideration of yarn surface properties, structural openness, and layer configuration. Fabrics that minimize adhesion points and allow easier contaminant release during cleaning cycles provide a significant advantage in real machine conditions.
Cleanability as a Core Design Parameter
A fabric’s ability to remain clean is directly linked to how well it interacts with the mill’s cleaning systems. Therefore, cleanability must be integrated into the design phase itself. This includes ensuring compatibility with high-pressure showers, resistance to chemical cleaning agents, and structural durability under continuous cleaning exposure. A fabric that performs well initially but degrades due to cleaning stress fails to deliver true lifecycle value.
Process Conditions Must Influence Design
Fabric performance is not isolated from the operating environment. Factors such as furnish composition, wet-end chemistry, retention programs, and machine speed significantly influence contamination behavior. Manufacturers must therefore adopt a more collaborative approach, aligning fabric design with actual machine conditions. This includes advising mills on cleaning strategies and adjusting designs based on furnish quality, especially in high-recycled-content systems.
Lifecycle Stability Defines Success
The true benchmark of a forming fabric is not its initial permeability but its ability to maintain consistent performance over time. Fabrics that resist contamination, recover effectively after cleaning, and sustain drainage uniformity throughout their lifecycle contribute directly to machine stability and cost efficiency. This shift from initial performance to lifecycle performance represents a critical evolution in fabric engineering philosophy.
Final Perspective
Fabric contamination and stickies build-up are not merely maintenance concerns—they are fundamental process challenges that influence drainage, sheet quality, energy consumption, and overall machine efficiency.
For paper makers, the focus must shift toward proactive monitoring and optimized cleaning strategies. For forming fabric manufacturers, the emphasis should be on designing fabrics that resist contamination and maintain cleanability throughout their operational life.
When both perspectives align, the outcome is a more stable process, improved product quality, and a measurable reduction in operating costs.
At PMC CENTRE, we work closely with paper mills and fabric manufacturers to identify hidden performance gaps related to contamination, drainage, and fabric behavior under real operating conditions.
If you are facing recurring issues in forming or press section performance, it may be time to look deeper into the fabric condition and cleaning strategy.Let’s connect and explore practical, data-driven solutions for your machine.
Reference:
Best Practices for Cleaning Forming Fabrics and Press Felts – TAPPI / Paper360https://paper360.tappi.org/2024/02/07/best-practices-for-cleaning-forming-fabrics-and-press-felts/
PMC CENTRE AI is the digital extension of this independent platform. It blends specialised PMC knowledge with structured AI support to provide practical guidance, troubleshooting insights, and current technical updates for forming fabrics, press felts, and dryer fabrics. Designed for professionals across the PMC ecosystem, it offers fast, unbiased support while reinforcing human judgement and real-world machine conditions. Get access here: www.pmccentre.com/pmc-centre-ai
Comments