Press Fabric Technology: Maximizing Nip Dewatering Efficiency

The Science of Press Section Dewatering

The press section removes approximately 30–40% of the water from the sheet, making it the most cost-effective dewatering stage. Press fabric design directly affects nip dewatering efficiency.

Press Fabric Construction Types

Batt-on-Base (BOB):
Traditional design with needled batt layers on a woven base fabric. Suitable for standard applications.

Batt-on-Mesh (BOM):
Finer surface batt layers over an open mesh base. Superior performance for:

• High-speed machines
• Smooth sheet surface requirements
• Reduced sheet rewet

Laminated Press Fabrics:
Multi-layer construction optimized for:

• Void volume distribution
• Pressure uniformity
• Batch-to-batch consistency

Void Volume Optimization

Void volume determines how much water the fabric can handle:

• Higher void volume = Greater water handling capacity
• But excessive void volume can reduce sheet surface quality
• The optimal balance depends on basis weight and speed

Stratified Batt Design

Advanced press fabrics use layered batt construction:

1. Fine surface batt layer (sheet side) — smooth finish
2. Medium intermediate batt layer — water transfer
3. Coarse base batt layer — structural support

This stratified approach optimizes dewatering efficiency while maintaining sheet quality.