Product Introduction 
The Filter Paper air permeability tester operates on the constant differential pressure principle. A stable pressure difference is created across the specimen, and the air permeability is characterized by measuring the gas flow rate passing through a defined specimen area per unit time. A high-precision pressure sensor monitors the differential pressure in real time, while a microcomputer digital feedback system dynamically adjusts the suction volume to maintain a constant set pressure. The instrument is equipped with multiple specimen area rings and precision nozzles, allowing users to select the most suitable configuration based on material permeability characteristics. Test results are displayed directly on the touchscreen, with automatic conversion between permeability and flow rate.

Key Features 
Microcomputer Digital Feedback Control High-precision pressure sensor and digital feedback dynamic suction volume adjustment automatically track and measure differential pressure at each point with outstanding stability and repeatability.
Wide Range, High Accuracy Differential pressure range 0-4000 Pa, permeability 0.2-12826 mm/s, measurement error ≤±2%, meeting full-range testing from low to high permeability materials.
Multiple Area Rings and Nozzles Four specimen area rings (5/20/50/100 cm²) and 11 nozzles (0.8-20 mm) flexibly accommodate materials with different permeability characteristics.
Full-Range Point-by-Point Calibration All test nozzles are calibrated point-by-point across the full range, ensuring accurate and reliable data.
Large Data Storage Capacity 16-bit single-chip microcomputer control with strong anti-interference, storing up to 5000 test records for easy data traceability and analysis.
Touchscreen with Bilingual Display Large touchscreen with support for both Chinese and English interfaces, directly displaying permeability and flow rate without manual chart conversion.
One-Touch Conversion, Efficient and Convenient Automatically displays all set values and freely converts between permeability and flow rate, significantly improving testing efficiency.
Print Output Function Equipped with a printer interface for printing standard test reports for documentation and archiving.

Main Technical Specifications 

FAQ
1. What materials are suitable for this air permeability tester?
It is primarily used for measuring the air permeability of filter paper, filtration materials, non-woven fabrics, and various breathable papers and textiles. Other sheet-like breathable materials within the pressure and flow range can also be tested.

2. How do I choose the right area ring and nozzle?
The choice depends on the specimen's permeability characteristics. Use a smaller area ring and larger nozzle for highly permeable materials, and the opposite for low-permeability materials. With multiple configurations available, optimal settings can be determined through preliminary trials.

3. What is the difference between air permeability and air flow rate?
Air permeability is the volume of gas passing through a unit area of specimen per unit time (mm/s), reflecting the intrinsic permeability of the material regardless of area. Air flow rate is the actual gas flow through a specimen of a given area. The instrument freely converts and displays both.

4. Why do nozzles need point-by-point calibration?
Each nozzle has slightly different flow coefficients across different flow ranges. Point-by-point calibration corrects these non-linear deviations, ensuring high accuracy and linearity of measurement data across the full range.

5. What does 5000 data storage mean? Can data be exported?
The instrument can save up to 5000 test records for easy historical data review. A printer interface is provided for printing reports. For electronic data export, please consult our technical team.

6. Does the instrument require regular calibration?
Periodic verification using standard permeability samples or calibration plates is recommended. If data deviation exceeds the allowable range, contact our after-sales team for professional calibration.

After-Sales Service 
Established in 2007 and with nearly two decades of experience, Shandong Annimet Instrument Co., Ltd. is a professional manufacturer integrating R&D, production, and sales of laboratory testing and sample preparation equipment. Quality is our foundation. We are your bridge from concept to reality. We deliver more than just instruments — we deliver confidence. This filter paper air permeability Tester comes with a 12-month warranty and lifetime technical support. Our professional team offers 24/7 service response, free installation guidance, operation training, and permeability testing method consultation. For any inquiries, please contact our customer service team; we are dedicated to providing comprehensive pre-sales, in-sales, and after-sales support. Hotline: 400-9933-057, Email: anmt_test@126.com.