In the manufacturing of Paper Machine Clothing (PMC)—including forming fabrics, press felts, and dryer fabrics—air permeability is a critical parameter. It determines the drainage capacity, vacuum efficiency, drying rate of the paper web, and overall fabric permeability.
1. Equipment Comparison Overview
| Manufacturer | Model / Style | Measurement Range | Key Dimensions | Est. Price (USD) | Contact Method |
| Valmet | Permtest MK4 (Handheld/Portable) | 0 – 2,000 m/min | 250 x 120 x 80 mm | $12,000 – $18,000 | valmet.com |
| TEXTEST Instruments | FX 3300 LabAir IV (Auto Benchtop) | 1 – 10,000 l/m²/s | 400 x 650 x 710 mm | $15,000 – $25,000 | textest.ch |
| ABB (L&W) | L&W Air Permeance (High Precision) | 0.003 – 100 µm/Pa·s | 450 x 400 x 530 mm | $20,000 – $35,000 | abb.com |
| Frank-PTI | Air Permeability Tester (Modular) | Per ISO/TAPPI Standards | 600 x 220 x 520 mm | $12,000 – $22,000 | frank-pti.com |
| Gurley Precision | Model 4340 (Automatic) | 0.1 – 50k Gurley Sec | 200 x 400 x 400 mm | $8,000 – $15,000 | gurley.com |
| ChiuVention | AirFicient (Digital) | 0.1 – 12,000 mm/s | 600 x 700 x 1100 mm | $5,000 – $10,000 | chiuvention.com |
2. Detailed Equipment Profiles
Valmet Permtest MK4
The Permtest MK4 is the industry-leading portable device specifically designed for the paper mill environment. It allows for “on-machine” measurement without needing to cut fabric samples.
Monitoring air permeability is essential for ensuring optimal manufacturing conditions in the PMC industry, as it directly impacts product quality and performance.
Understanding the role of air permeability in fabric performance is crucial for achieving quality results in paper manufacturing.
Style: Handheld, battery-operated, digital.
Best For: Field service, troubleshooting fabric plugging/contamination, and monitoring fabric life cycles on the paper machine.
Measurement Principle: Uses high-speed suction and digital sensors to calculate flow instantly upon contact with the fabric surface.
TEXTEST FX 3300 LabAir IV
The FX 3300 is considered the “gold standard” for laboratory-based PMC quality control. It is used by major manufacturers (Voith, Andritz, Albany, etc.) to certify fabrics before shipment.
Style: Benchtop, automated.
The importance of consistent air permeability cannot be overstated; it provides valuable insights for adjustments during manufacturing processes.
Best For: High-volume laboratory testing and R&D. It covers everything from dense felts to very open dryer screens using an automatic orifice changer.
Advantage: Extremely fast measurement cycle and pneumatic clamping to ensure consistent results.
ABB (Lorentzen & Wettre) Air Permeance Tester
ABB’s L&W line is synonymous with high-precision pulp and paper testing. While often used for paper sheets, their wide-range modules are used for high-end fabric R&D.
Style: Benchtop, high-precision.
Best For: Laboratory settings where extreme accuracy and repeatability are required for specialized grades.
Gurley Precision Model 4340
The Gurley “Densometer” is a traditional method updated for the digital age. It measures the time required for a specific volume of air to pass through a sample.
Style: Benchtop.
Best For: Denser materials. Note that for very high-permeability dryer fabrics, the TEXTEST or Valmet models are often more efficient.
Testing air permeability helps identify fabric characteristics that are crucial for meeting industry standards.
3. Key Selection Criteria for PMC Manufacturers
Laboratory vs. Field Use:
Laboratory (TEXTEST/ABB/Frank-PTI): Essential for final QC certification. These units provide the most controlled environment and highest accuracy.
Field (Valmet MK4): Essential for service technicians. It proves the performance of the fabric to the customer while it is in operation.
Standards Compliance: Most units are designed to comply with ISO 9237 (Textile air permeability) or TAPPI T251 (Paper and fabric air permeability).
Clamping Area: Ensure the test head size (e.g., 20 cm², 38 cm², or 100 cm²) matches your specific customer requirements or internal standards.
Contact for Purchase: For all mentioned equipment, purchasing is typically done through regional sales offices. Valmet and ABB usually require a direct inquiry to their “Pulp & Paper Service” divisions.
In KEYLIFE, we are using Textester in our daily manufacturing of press felts, forming fabric, and dryer fabric. The air permeability of our PMC is well managed, ensuring optimal performance and durability in various applications while consistently monitoring permeability.
