Pumps, Meters and flow valves
...and their problems with Vapour Permeability

Homes, offices and factories are all major users of pumps, meters and flow valves, many of them have problems caused by vapour (often water vapour) permeability. The pumps etc are usually made from materials that are excellent at keeping liquids out, but sadly this does not affect their ability to prevent gases flowing straight through them and forming a condensate on the other side.   EVOH, PVOH, cellulose and many other materials fall into this category and allow vapour to flow through almost unhindered. Worse still, manufacturing processes such as thermoforming can degrade performance to a quarter of its original value.  

For information on permeability testing click for Pumps and meters click here

Click here for an article on Testing for water vapour permeability of materials and containers

However, measuring the vapour permeability of either the material from which the pumps, valves or metres are tested, or even components or the finished products themselves has become easy

Problems with vapour permeability have led to expensive product recalls and replacements.  What's more our equipment can optionally measure vapour permeability not only with respect to water vapour, but also for hydrocarbons, oxygen, nitrogen, CO2 and most other gases.

Click here for Engineering Live's piece on pumps and meters and here for Plant Engineering's take on the issue

For equipment to measure permeability click here

For background information on permeability click here