Patent ID: 8113764

Claim:
A steam turbine comprising: a first turbine section including a flow of high temperature, high pressure steam; a second turbine section; a shaft operatively connecting the first turbine section and the second turbine section; a packing assembly positioned about the shaft, the packing assembly limiting an amount of the flow of high temperature, high pressure steam passing along the shaft from the first turbine section to the second turbine section; a first conduit fluidly connected to the packing assembly, the first conduit being adapted to introduce a flow of low temperature, low pressure steam to the packing assembly; a second conduit fluidly connected to the packing assembly downstream from the first turbine section and upstream from the first conduit, the second conduit receiving a portion of the high temperature, high pressure steam passing into the packing assembly from the first turbine section; a valve fluidly connected to the second conduit, the valve being adapted to be selectively operated to allow the high temperature, high pressure steam to mix with the low pressure, low temperature steam in the second conduit; one or more sensors mounted to the second conduit; and a controller operatively connected to the one or more sensors, the controller being programmed to determine an amount of high temperature, high pressure steam leaking into the packing assembly from the first turbine portion.