Controlling a rabbet load and air/oil seal temperatures in a turbine
Abstract
During a standard fired shutdown of a turbine, a loaded rabbet joint between the fourth stage wheel and the aft shaft of the machine can become unloaded causing a gap to occur due to a thermal mismatch at the rabbet joint with the bearing blower turned on. An open or unloaded rabbet could cause the parts to move relative to each other and therefore cause the rotor to lose balance. If the bearing blower is turned off during a shutdown, the forward air/oil seal temperature may exceed maximum design practice criterion due to "soak-back." An air/oil seal temperature above the established maximum design limits could cause a bearing fire to occur, with catastrophic consequences to the machine. By controlling the bearing blower according to an optimized blower profile, the rabbet load can be maintained, and the air/oil seal temperature can be maintained below the established limits. A blower profile is determined according to a thermodynamic model of the system.
- Inventors:
-
- Niskayuna, NY
- Issue Date:
- Research Org.:
- General Electric Co., Schenectady, NY (United States)
- OSTI Identifier:
- 874379
- Patent Number(s):
- 6379108
- Assignee:
- General Electric Company (Schenectady, NY)
- Patent Classifications (CPCs):
-
F - MECHANICAL ENGINEERING F01 - MACHINES OR ENGINES IN GENERAL F01D - NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- DOE Contract Number:
- FC21-95MC31176
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- controlling; rabbet; load; airoil; seal; temperatures; turbine; standard; fired; shutdown; loaded; joint; fourth; stage; wheel; shaft; machine; unloaded; causing; gap; occur; due; thermal; mismatch; bearing; blower; move; rotor; lose; balance; forward; temperature; exceed; maximum; design; practice; criterion; soak-back; established; limits; fire; catastrophic; consequences; optimized; profile; maintained; below; determined; thermodynamic; model; /415/
Citation Formats
Schmidt, Mark Christopher. Controlling a rabbet load and air/oil seal temperatures in a turbine. United States: N. p., 2002.
Web.
Schmidt, Mark Christopher. Controlling a rabbet load and air/oil seal temperatures in a turbine. United States.
Schmidt, Mark Christopher. Tue .
"Controlling a rabbet load and air/oil seal temperatures in a turbine". United States. https://www.osti.gov/servlets/purl/874379.
@article{osti_874379,
title = {Controlling a rabbet load and air/oil seal temperatures in a turbine},
author = {Schmidt, Mark Christopher},
abstractNote = {During a standard fired shutdown of a turbine, a loaded rabbet joint between the fourth stage wheel and the aft shaft of the machine can become unloaded causing a gap to occur due to a thermal mismatch at the rabbet joint with the bearing blower turned on. An open or unloaded rabbet could cause the parts to move relative to each other and therefore cause the rotor to lose balance. If the bearing blower is turned off during a shutdown, the forward air/oil seal temperature may exceed maximum design practice criterion due to "soak-back." An air/oil seal temperature above the established maximum design limits could cause a bearing fire to occur, with catastrophic consequences to the machine. By controlling the bearing blower according to an optimized blower profile, the rabbet load can be maintained, and the air/oil seal temperature can be maintained below the established limits. A blower profile is determined according to a thermodynamic model of the system.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jan 01 00:00:00 EST 2002},
month = {Tue Jan 01 00:00:00 EST 2002}
}