Water sensor that detects tank or vessel leakage

A method for determining the rate of hydrocarbon product leakage from the volume of water entering a liquid storage vessel whose contents are under negative pressure, comprising the steps of:

• determining the longitudinal angle of inclination of the vessel with respect to the horizon;
• measuring the depth of the water in the vessel at predetermined time intervals with an apparatus for continuously monitoring the level of water in the vessel,
• the apparatus comprising:
• a magnetostrictive sensor comprised of a float slidably mounted on a rod and a means for generating an electrical signal proportional to the location of the float on the rod, the float sliding in response the level of water in the vessel;
• a cylindrical probe body having a first and a second end and a longitudinal slot therethrough, the rod of said magnetostrictive sensor extending through the slot, the slot being sealed against fluid influx when the rod extends therethrough;
• a protective sleeve threadably engaged to the first end of said probe body so as to encase the float of said magnetostrictive sensor, said sleeve having openings therein to permit fluid flow therethrough;
• means for processing the electrical signal generated by said magnetostrictive sensor and for transmitting the processed signal to another location for further processing;
• and
• an external housing threadably connected to the second end of said probe body opposite the first end so as to encase said processing and transmitting means and seal said processing and transmitting means against fluid influx;
• calculating the volume of water in the vessel from each depth measurement and the angle of inclination;
• and
• ascertaining the rate of change in calculated volume of water in the vessel over time from which the rate of hydrocarbon product leakage from the vessel is determined.