摘要 |
<p>A device and method for detecting average temperature, particularly adapted for determining the average liquid temperature in an underground horizontally disposed cylindrical tank. The sensing element, in the form of a wire of known temperature versus electrical resistance characteristic is contained within an extensible cylindrical helical coil of plastic tubing which can be introduced into the tank and extended to the overall height of the liquid by gravity through a weight on one end of the coil or by the use of an extendible rod inserted into the center of the coil. The tubing is preformed or arranged relative to the extensible rod to present a greater number of coil turns at the center of the tank to compensate for greater liquid volume.</p> |