Surface film monitor for oil and fuel - insulating coating on floating electrode is dissolved and circuit established

摘要

The surface film detector for conducting fluids is particularly useful for monitoring the presence of oil or other fuels in water. The monitor head consists of a float having an upper and lower component (1,5) separated by spacers (6); the weight and buoyancy of the float is such that any floating film of oil can pass between the two halves of the float. Vertical electrodes pass from the upper to the lower float sections, passing through the central zone exposed to surface film (8). One electrode is formed from a bare metal element (4), the second electrode being covered with a material soluble in oil or other fuel. The presence of the fuel film dissolves the insulating coating and an electrical circuit is established through the water between the two electrodes.