GBPI N500L – Differential Pressure Gas Permeability Tester (Manometric Method)

The GBPI N500L is an advanced, high-precision differential pressure gas permeability tester designed for evaluating the barrier performance and gas transmission rate (GTR) of plastic films, composite packaging laminates, barrier sheets, metalized foils, and industrial membranes. Built in strict accordance with recognized differential pressure standards including ISO 15105-1, ISO 2556, ASTM D1434 (Method M), JIS K7126-1, and GB/T 1038, this benchtop analyzer delivers comprehensive barrier data for packaging R&D and industrial quality assurance.

Unlike single-gas sensor systems, the vacuum differential pressure method is universally applicable across multiple inorganic test gases, including oxygen (O&sub2;), nitrogen (N&sub2;), carbon dioxide (CO&sub2;), helium (He), and air. The GBPI N500L differential pressure gas permeability tester functions by securing a circular test specimen between a high-pressure upper chamber and a lower vacuum chamber. Both chambers are initially evacuated to ultra-low pressure (<10 Pa) to degas the sample and eliminate residual atmospheric gases. Once high vacuum equilibrium is reached, the upper chamber is filled with test gas at a regulated constant pressure, creating a steep differential pressure gradient across the specimen thickness. As gas molecules permeate through the barrier matrix into the lower chamber, a high-precision absolute pressure transducer continuously monitors the micro-pressure increase over time to calculate the gas transmission rate, solubility coefficient, and diffusion coefficient.

Advanced Vacuum Transducer & Wide Dynamic Range

Equipped with an ultra-sensitive vacuum pressure transducer and high-grade electromagnetic vacuum valves, the N500L covers a broad permeability dynamic range from 0.02 to 50,000 cm³/(m²·24h·0.1MPa). This wide analytical spectrum allows testing of everything from ultra-high barrier pharmaceutical foils to permeable agricultural and breathable membrane structures.

Precise Temperature Regulation & Automated Testing

Permeation kinetics are highly sensitive to thermal fluctuations. The N500L features an integrated thermodynamic control system maintaining test cell temperature between 15 °C and 60 °C with ±0.1 °C stability. The entire evacuation, gas charging, pressure curve plotting, and endpoint detection sequence is automated through dedicated PC software, eliminating operator intervention.

The companion software delivers real-time pressure-versus-time curves, automatic steady-state tangent fitting, reference calibration film validation, and tamper-proof PDF test report generation conforming to modern laboratory data integrity standards.