Advanced Techniques For Acoustic Liquid Level Determination

Acoustic liquid level tests are performed successfully in many different applications throughout the world. Advanced techniques for acoustic liquid level analysis are required for wells where unusual conditions exist such as very shallow liquid levels, annular partial obstructions, flush pipe, short tubing joints, etc. Some wells have liners, upper perforations, paraffin, odd length of tubing joints, poor surface connections and other conditions which result in an acoustic trace that may be very difficult to interpret. Normally, the computer software locates the liquid level and automatically processes collar reflections to accurately count almost all of the collars from the initial blast to the liquid level. This automatic analysis will determine the liquid level depth for 95% of the wells. However, some wells have conditions or anomalies that these procedures will not function as desired. This paper describes special advanced techniques that can be used to determine the liquid level in wells with these unusual conditions.