ONLINE VALVE DIAGNOSTIC MONITORING SYSTEM

An online valve monitoring system senses operational characteristics of a valve and provides a diagnosis of aberrations in the characteristics. Sensors, coupled to a valve, supply sensor signals as output to a data acquisition system to be transmitted to a remote location. An I/O processor at the remote location receives the sensor signals and a diagnostic processor extracts characteristic features from the sensor signals as deviations from baseline data for the valve. An expert system applies a rule base to the characteristic features individually or in combination to diagnose the causes of the deviations. Use of multiple sensors increases the confidence of the diagnosis which can be immediately communicated to an operator and used for scheduling maintenance of the valve. Use of this diagnosis and the trend line of historical data permits scheduling of preventive maintenance.