摘要 |
<p>A method and apparatus for detecting perforations in an underground fuel storage tank, employs the creation of a partial vacuum in the tank and a pressure difference across the tank wall, to cause air to pass through the perforation, and a hydrophone to sense the acoustic waves produced by the formation of air bubbles in the fuel. The acoustic waves of the bubbles caused by the air passage are sensed by a hydrophone and processed to provide an electrical signal indicative of the presence of the perforation. A water level sensor is also used to detect the level of water beneath hydrocarbon fuel in the tank. The method and apparatus can also be used with above ground fuel storage tanks and other types of above and below ground storage tanks.</p> |