A Testing Equipment for Measuring Fuel Permeability of Plastic Fuel Line Tubing

An easily implemented laboratory method for measuring fuel-permeability through plastic tubes, while controlling fuel temperature and pressure independently, is presented. This is achieved with a recirculating system in which fuel permeated through the tubing wall is evaporated and collected by a controlled flow of nitrogen and absorbed in activated carbon.

A formula is given by which fuel-permeability under standard conditions of temperature and pressure can be predicted for plastic parts of any shape and thickness. A particular embodiment of the test equipment allows, in addition, the measurement of tube length change under the same experimental conditions.