초록 ▼

A flow sensor includes a strap-on heater attached to a fluid conduit downstream of a drain valve and two differential temperature measuring thermocouples attached to the fluid conduit downstream of the heater. A monitoring system employing at least one of the flow sensors further includes a controll

A flow sensor includes a strap-on heater attached to a fluid conduit downstream of a drain valve and two differential temperature measuring thermocouples attached to the fluid conduit downstream of the heater. A monitoring system employing at least one of the flow sensors further includes a controller which receives the differential temperature signal produced by the two thermocouples, a signal indicative of a selected valve position, and a signal indicative of steam turbine operating condition, i.e., hot or cold. The controller includes a logic circuit for correlating the differential temperature value signal, the valve position signal and the steam turbine condition signal to a diagnosis of the drain valve condition.

대표청구항 ▼

A monitoring system for monitoring at least one drain valve disposed in a fluid conduit having a temperature affected by the presence of fluid flow, and producing a diagnosis of the condition of each drain valve as functional, clogged or stuck shut, stuck open, or cold fluid flow through the drain v

A monitoring system for monitoring at least one drain valve disposed in a fluid conduit having a temperature affected by the presence of fluid flow, and producing a diagnosis of the condition of each drain valve as functional, clogged or stuck shut, stuck open, or cold fluid flow through the drain valve, comprising: at least one flow sensor, each flow sensor including a heater attached to an exterior surface of the fluid conduit downstream of the drain valve, the heater, when energized, producing a thermal gradient along the fluid conduit which varies as a function of fluid flow, a first temperature sensing element attached to the exterior surface of the fluid conduit at a position spaced downstream of the heater and producing an output indicative of the temperature of the fluid conduit at the position of the first temperature sensing element, a second temperature sensing element attached to the exterior surface of the fluid conduit at a position spaced downstream of the first temperature sensing element, and producing an output indicative of the temperature of the fluid conduit at the position of the second temperature sensing element, and means responsive to the outputs of the first and second temperature sensing elements for producing a differential temperature output signal based on a difference between the temperature sensed at the first temperature sensing element and the temperature sensed at the second temperature sensing element, the differential temperature output signal having relatively greater and lesser values responsive to and thereby indicative of the presence and absence of fluid flow, drain valve position indicator means for producing and outputting a signal indicative of a selected position for each corresponding drain valve, operating condition indicator means for producing and outputting a signal indicative of an operating condition of the steam turbine, and control means responsive to the output signals of the operating condition indicator means, the differential temperature producing means, and the drain valve position indicator means, for outputting a signal indicative of a diagnosis of the drain valve, and display means, responsive to the output signal of the control means, for displaying the diagnosis of the drain valve.