Steam turbine and method for removing moisture from the steam turbine

Abstract

A steam turbine includes an inner casing that at least partially defines the steam flow path, a passage for extending through the inner casing to at least partially define a moisture flow path out of the steam flow path, and a seal operably connected to the passage. The seal has a first position associated with a first set of operating conditions within the steam flow path and a second position associated with a second set of operating conditions within the steam flow path.

What is claimed is: 
     
         1 . A steam turbine including a system for removing moisture from a steam flow path of the steam turbine, the steam turbine comprising:
 a. an inner casing that at least partially defines the steam flow path;   b. a passage extending through the inner casing to at least partially define a moisture flow path out of the steam flow path; and   c. a seal operably connected to the passage, wherein the seal has a first position associated with a first set of operating conditions within the steam flow path and a second position associated with a second set of operating conditions within the steam flow path.   
     
     
         2 . The steam turbine of  claim 1 , wherein the first set and the second set of operating conditions includes at least one of temperature, pressure, moisture level, or moisture flow rate. 
     
     
         3 . The steam turbine of  claim 1 , wherein the seal includes a temperature activated valve. 
     
     
         4 . The steam turbine of  claim 1 , wherein the seal includes a bimetallic actuator. 
     
     
         5 . The steam turbine of  claim 1 , wherein the seal includes a liquid-filled bellows. 
     
     
         6 . The steam turbine of  claim 1 , further comprising a predetermined temperature threshold that actuates the seal. 
     
     
         7 . The steam turbine of  claim 1 , wherein the seal includes a pressure activated valve. 
     
     
         8 . The steam turbine of  claim 7 , wherein the pressure activated valve activates at increasing or decreasing predetermined pressure differential thresholds. 
     
     
         9 . The steam turbine of  claim 1 , wherein the seal includes a variable clearance pressure packing. 
     
     
         10 . The steam turbine of  claim 1 , wherein the seal includes an electromechanical valve. 
     
     
         11 . The steam turbine of  claim 10 , further comprising at least one sensor communicatively coupled to a controller, wherein the controller is communicatively coupled to the seal. 
     
     
         12 . A method for removing moisture from a steam flow path based on operating conditions within the steam flow path of a steam turbine, comprising:
 a. flowing the moisture from the steam flow path through a passage defined through an inner casing of the steam turbine when a first set of operating conditions within the steam flow path exists; and   b. actuating a seal when a second set of operating conditions exists to reduce the moisture flow from the steam flow path.   
     
     
         13 . The method of  claim 12 , further comprising positioning a valve in the seal to reduce the moisture flow from the steam flow path. 
     
     
         14 . The method of  claim 12 , further comprising actuating the seal to stop the moisture flow from the steam path. 
     
     
         15 . A steam turbine comprising;
 a. an inner casing that at least partially defines a steam flow path;   b. a passage extending through the inner casing to at least partially define a moisture flow path out of the steam flow path; and   c. means for reducing moisture flow from the steam flow path.   
     
     
         16 . The steam turbine of  claim 15 , wherein the means comprises a temperature activated valve. 
     
     
         17 . The steam turbine of  claim 15 , wherein the means comprises at least one of a bimetallic actuator or a liquid-filled bellows. 
     
     
         18 . The steam turbine of  claim 15 , wherein the means comprises a pressure activated valve. 
     
     
         19 . The steam turbine of  claim 15 , wherein the means comprises a time activated seal. 
     
     
         20 . The steam turbine of  claim 15 , further comprising at least one sensor communicatively coupled to the means, wherein the at least one sensor is configured to sense at least one of a first operating condition or a second operating condition within the steam flow path.