Crane Nuclear, Inc.

Liberty Technologies, Inc.

David Q Heagerty

Robert L Leon

Martin Joseph Dowling

A method and apparatus for on-line detection of leaky emergency shutdown or other valves in a fluid transport system having an upstream pipe, a downstream pipe and the valve connected between the upstream pipe and the downstream pipe for controlling fluid flow through the system. The valve has at least one upstream seal and at least one downstream seal and an inner cavity effectively isolated by the seals from the fluid flow stream through the system. The apparatus comprises a first transducer in fluid communication with the fluid flow stream at at least one of: a predetermined distance upstream of the upstream seal; and a predetermined distance downstream of the downstream seal. The first transducer is for sensing pressure pulsations resulting from at least one of: dynamic energy due to fluid flow through the transport system; and transient energy within the fluid in the transport system after the valve is closed and for generating representative electrical signals as a function of time. A second transducer is in fluid communication with the inner cavity of the valve for sensing substantially simultaneous pressure pulsations within the inner cavity and for generating second representative electrical signals as a function of time. An analyzer receives the first and second electrical signals and generates at least one of: a frequency response function; and a coherence function. The generated function is sufficiently averaged to provide a meaningful measure of the degree to which the two electrical signals are related to thereby indicate whether, and to what extent, sensed pressure pulsations within the fluid transport system are passed through at least one of the seals to the inner cavity.

Method and apparatus for on-line detection of leaky emergency shut down

A method for determining at least one operating parameter to determine the operating condition of a polyphase electric motor system comprises sensing the instantaneous current signal and the instantaneous voltage signal as a function of time for more than one electrical phase of the motor. The sensed current signals and the sensed voltage signals are both amplitude demodulated and phase demodulated to provide amplitude demodulated current and voltage signals as a function of time and phase demodulated current and voltage signals as a function of time. The resulting amplitude and phase demodulated signals are used to determine one or more of the following electrical parameters as a function of time: total real power, real power per phase, total reactive power, reactive power per phase, total apparent power, apparent power per phase, overall power factor, power factor per phase, electrical impedance per phase, and electrical balance.

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Glen Mills, PA, United States of America

David Q Heagerty