Since the introduction of the Sampler there have been various approaches to carrying out the Shell Water Detector (SWD) test, but there have been different problems associated with all of them. The best SWD test is obtained when the capsule is immersed directly into the main fuel sample because there is then no issue with dead volumes and unrepresentative fuel properties. It is also desirable to make the whole test more user friendly and reduce the consumption of syringes. So we set out with these objectives in mind when we developed our Air Powered SWD.
The Air Powered SWD consists of a graduated plastic tube which is permanently fixed to the sampler hinged lid, close coupled to a vacuum generator which creates a vacuum in the tube when air pressure is applied to the inlet connection, and this vacuum draws fuel through the SWD capsule.