This paper describes the development and testing of a structural-acoustic sensing and alert system that continuously monitors a pipeline without the need of an external power source. This system is based on Mide's patented PowerAct conformable packaged piezoelectric actuator and sensor. These sensors are extremely sensitive with very high gain and can detect the most minute and high frequency strains. Since leaks in high-pressure gas pipes fit this description, there is currently no better sensor to apply to the specific problem. The results of this effort led to the design of a system that can sense, locate and report leaks and impacts in a buried pipeline system. This system is estimated to cost less than $400 / km of pipe. In conclusion, the results of this paper are encouraging and indicate that it is feasible to use the PowerAct sensors in a cost effective system to locate impacts and leaks in pipelines.
A comparison of different commercially available packaged piezoelectric actuators is presented. The comparisons are based on force, stress and strain performance at similar field densities. A new metric of comparison, based on energy efficiency, is introduced. This paper provides designers with useful information on actuators and actuator performance for industrial applications. The QuickPack and PowerAct actuators remain the only packaged piezoelectric actuators to be produced in high volume and to feature in commercial applications.