What Technical Parameters Matter Most in Tissue Machines

What Technical Parameters Matter Most in Tissue Machines?

Tissue machines are the core equipment in the papermaking industry for producing toilet paper, facial tissues, and other household papers. Their performance directly impacts product quality, production efficiency, and operational costs. This article explores the most critical technical parameters in tissue machines to help practitioners optimize equipment selection and production management.

1. Operating Speed

Operating speed reflects the production capacity of a tissue machine, typically measured in meters per minute (m/min). Modern high-speed tissue machines can reach 200-230 m/min or even higher.

• Impact: Higher speeds increase output but require balancing stability and energy consumption.
• Key Consideration: Choose an appropriate speed based on paper grade (e.g., parent roll vs. finished product) and process requirements to avoid breaks or quality degradation.

2. Web Width

Web width refers to the (cross-directional) size of the paper produced, commonly ranging from 1.85-2.8 meters.

• Impact: Wider webs improve single-run efficiency but significantly increase equipment investment and maintenance costs.
• Key Consideration: Design based on market demand (e.g., roll size for toilet paper) and factory space constraints.

3. Basis Weight

Basis weight is the weight of paper per unit area, measured in grams per square meter (g/m²). Tissue paper typically has a basis weight of 13–40 g/m².

• Impact: Basis weight affects softness, absorbency, and strength. Lower basis weights require process optimization to prevent transparency or tearing.
• Key Consideration: Adjust based on product positioning (premium vs. budget) and ensure uniformity.

4. Drying Capacity

Tissue production relies on hot air drying or Yankee dryers to remove moisture. Drying efficiency depends on:

• Hot air temperature and velocity: Higher values accelerate drying but may damage fibers.
• Yankee dryer diameter and steam pressure: Larger diameters (e.g., 4–5 meters) with high-pressure steam (8–10 bar) enhance drying.
• Impact: Insufficient drying leads to high moisture content and mold risk; excessive drying increases energy use and reduces softness.

5. Press Section Pressure

The press section removes water via mechanical squeezing, with pressure measured in kilonewtons per meter (kN/m).

• Impact: Proper pressure reduces drying energy but excessive force collapses the paper structure, lowering softness.
• Key Consideration: Use low pressure or shoe presses for ultra-soft tissues.

6. Forming Fabric and Felt Quality

• Forming fabric: Affects drainage uniformity and surface quality; choose appropriate mesh count (e.g., 60–80 mesh) and material.
• Felt: Requires high permeability and wear resistance for stable drainage and web running.
• Impact: Poor-quality fabrics/felts cause defects like holes or streaks, increasing downtime.

7. Automation and Control Systems

Modern tissue machines rely on DCS (Distributed Control Systems) and QCS (Quality Control Systems) for:

• Real-time monitoring: Speed, basis weight, moisture, etc.
• Automatic adjustments: Optimize processes based on data to minimize human intervention.
• Impact: Improve production stability and product consistency while reducing waste.