Eccentric coupling device and method for coupling mating casings in a turbomachine

Abstract

Turbomachines, coupling devices and methods for coupling a first casing and an second casing together are provided. The first casing and second casing include mating bore holes defined in mating flanges thereof, which may be misaligned. The coupling device may include a bushing insertable and positionable within one of the mating bore holes, and a pin insertable and positionable within the bushing and the other of the mating bore holes. The bushing and pin may each include eccentric features which may facilitate insertion into the mating bore holes when the bore holes are misaligned, thus coupling the first casing and second casing together.

What is claimed is: 
     
         1 . A coupling device for coupling a first casing and a second casing of a gas turbine system together, the first casing comprising a first flange that defines a first flange bore hole and the second casing comprising a second flange that defines a second flange bore hole, the first flange and the second flange abutted together, the coupling device comprising:
 a bushing insertable and positionable within one of the first flange bore hole and the second flange bore hole; and   a pin insertable and positionable within the bushing and the other of the first flange bore hole and the second flange bore hole,   wherein the bushing and the pin each comprise an eccentric feature.   
     
     
         2 . The coupling device of  claim 1 , wherein the bushing comprises an outer surface sized to contact an inner surface of the one of the first flange bore hole and the second flange bore hole when the bushing is inserted in the one of the first flange bore hole and the second flange bore hole. 
     
     
         3 . The coupling device of  claim 1 , wherein the bushing defines a bushing bore hole. 
     
     
         4 . The coupling device of  claim 3 , wherein a longitudinal axis of the bushing bore hole is offset from a longitudinal axis of the bushing. 
     
     
         5 . The coupling device of  claim 3 , wherein the pin comprises a first portion and a second portion, the second portion having a width that is less than a width of the first portion. 
     
     
         6 . The coupling device of  claim 5 , wherein the first portion comprises an outer surface sized to contact an inner surface of the bushing bore hole when the first portion is inserted in the bushing bore hole, and wherein the second portion comprises an outer surface sized to contact an inner surface of the other of the first flange bore hole and the second flange bore hole when the second portion is inserted in the other of the first flange bore hole and the second flange bore hole. 
     
     
         7 . The coupling device of  claim 5 , wherein a longitudinal axis of the second portion is offset from a longitudinal axis of the first portion. 
     
     
         8 . A turbomachine, the turbomachine comprising:
 a first casing, the first casing comprising a first flange that defines a first flange bore hole;   a second casing, the second casing comprising a second flange that defines a second flange bore hole, wherein the first flange and the second flange are abutted together; and   a coupling device coupling the first casing and the second casing together, the coupling device comprising:
 a bushing positioned within one of the first flange bore hole and the second flange bore hole; and 
 a pin positioned within the bushing and the other of the first flange bore hole and the second flange bore hole, 
 wherein the bushing and the pin each comprise an eccentric feature. 
   
     
     
         9 . The turbomachine of  claim 8 , wherein the bushing comprises an outer surface contacting an inner surface of the one of the first flange bore hole and the second flange bore hole. 
     
     
         10 . The turbomachine of  claim 8 , wherein the bushing defines a bushing bore hole. 
     
     
         11 . The turbomachine of  claim 10 , wherein a longitudinal axis of the bushing bore hole is offset from a longitudinal axis of the bushing. 
     
     
         12 . The turbomachine of  claim 10 , wherein the pin comprises a first portion and a second portion, the second portion having a width that is less than a width of the first portion. 
     
     
         13 . The turbomachine of  claim 12 , wherein the first portion is positioned within the bushing and the second portion is positioned within the other of the first flange bore hole and the second flange bore hole. 
     
     
         14 . The turbomachine of  claim 13 , wherein the first portion comprises an outer surface contacting an inner surface of the bushing bore hole, and wherein the second portion comprises an outer surface contacting an inner surface of the other of the first flange bore hole and the second flange bore hole. 
     
     
         15 . The turbomachine of  claim 12 , wherein a longitudinal axis of the second portion is offset from a longitudinal axis of the first portion. 
     
     
         16 . The turbomachine of  claim 8 , wherein the bushing is fixedly connected to the one of the first flange bore hole and the second flange bore hole, and wherein the pin is fixedly connected to the bushing and the other of the first flange bore hole and the second flange bore hole. 
     
     
         17 . The turbomachine of  claim 8 , wherein the first casing is a turbine casing and the second casing is an exhaust casing. 
     
     
         18 . The turbomachine of  claim 8 , wherein a longitudinal axis of the first flange bore hole is offset from the longitudinal axis of the second flange bore hole. 
     
     
         19 . A method for coupling a first casing and a second casing of a gas turbine system together, the method comprising:
 inserting a bushing into a bore hole defined in a flange of the first casing or the second casing;   rotating the bushing to align with a mating bore hole defined in a flange of the other of the first casing or the second casing;   inserting a pin into the bushing;   rotating the pin to align with the mating bore hole defined in the flange of the other of the first casing or the second casing; and   inserting the pin into the mating bore hole,   wherein the bushing and the pin each comprise an eccentric feature.   
     
     
         20 . The method of  claim 19 , wherein a longitudinal axis of the bore hole defined in the flange of the first casing is offset from a longitudinal axis of the bore hole defined in the flange of the second casing.