Abstract: A monitoring system utilizing an ultrasonic transducer wherein the power level of the transducer operating signals is raised while maintaining the gain about unity for permitting the use of relatively longer signal paths between a signal generator and the transducer.

Abstract: A production monitoring system wherein the velocity of fluid flowing through a monitored flowline is plotted with respect to time for a period of time sufficient to establish a repeatable pattern (production flow characteristics profile) and wherein an alarm value and an alarm delay time are determined from the production flow characteristics profile. In one aspect, the velocity of the fluid flowing through the monitored flowline is detected and an output indication indicating a problem production condition is provided in response to a detected velocity below the alarm value for a period of time in excess of the alarm delay time.