water vapor transmission analyzer

The water vapor transmission analyzer can measure the water vapor transmission rate of various materials under different kinds of  restricted conditions. The test conditions can simulate the actual application environment. The test results are featured with accuracy and reproducibility.
 
Operating Principle

 Two independent gas streams are maintained on the two sides of a sample at the desired temperature. Humidity and gas flow rates are measured. The transmission rate through the sample is computed using mass balance.
 
 
 
Where

n = moles Φ = humidity M = flow rate
t = time p = equilibrium vapor pressure
ί = inlet o = outlet P = total pressure

Application

The PMI Water Vapor Transmission Analyzer is capable of measuring water vapor transmission through porous media such as textiles, leathers, man made materials, membranes, nonwovens, and fabrics used in numerous high technology components and consumer products manufactured by a variety of industries.

The instrument has the unique ability to measure vapor transmission rate over a wide range of humidity, temperature, and pressure under gradients of humidity, temperature, and pressure encountered in application environments.
 
Features

· Humidity on any side can be maintained between 5 and 95%
· Any desired pressure gradient can be maintained.
· Any desired test temperature can be achieved.
· Simultaneous pressure and humidity gradients can be maintained
· Flat samples in a wide range of sizes can be accommodated
· Completely automated test implementation, data acquisition, data store and data simplification.
 
 Technical Parameters