Sealing band having bendable tang with anti-rotation in a turbine and associated methods

Abstract

The turbine includes a plurality of successive stages each having a rotatable disk and blades carried thereby. A pair of adjacent rotatable disks define an annular gap therebetween and have respective opposing sealing band receiving slots aligned with the annular gap. At least one of the rotatable disks has at least one notch therein coupled to the respective sealing band receiving slot, and a sealing band is in the opposing sealing band receiving slots to seal the corresponding annular gap. The sealing band includes at least one sealing strip and at least one movable locking tang carried thereby and extending into the at least one notch to define an anti-rotational feature for the sealing band.

1 . A turbine comprising:
 a plurality of successive stages each comprising a rotatable disk and blades carried thereby, at least one pair of adjacent rotatable disks defining an annular gap therebetween and having respective opposing sealing band receiving slots aligned with the annular gap, at least one of the rotatable disks having at least one notch therein coupled to the respective sealing band receiving slot; and   a sealing band in the opposing sealing band receiving slots to seal the corresponding annular gap;   said sealing band comprising at least one sealing strip and at least one movable locking tang carried thereby and extending into the at least one notch to define an anti-rotational feature for the sealing band.   
     
     
         2 . The turbine according to  claim 1 , wherein the at least one movable locking tang and the at least one sealing strip are integrally formed as a monolithic unit; and wherein said movable locking tang is bendable with respect to adjacent portions of the at least one sealing strip. 
     
     
         3 . The turbine according to  claim 2 , wherein the at least one sealing strip comprises at least one metal sealing strip. 
     
     
         4 . The turbine according to  claim 1 , wherein the at least one movable locking tang has a distal end being movable from a coplanar position relative to adjacent portions of the at least one sealing strip to a bent position extending radially inwardly from adjacent portions of the at least one sealing strip. 
     
     
         5 . The turbine according to  claim 4 , wherein the distal end is flush with adjacent side edges of the at least one sealing strip when in the coplanar position. 
     
     
         6 . The turbine according to  claim 1 , wherein the at least one movable locking tang has a generally rectangular shape with a proximal end connected to adjacent medial portions of the at least one sealing strip and opposing sides being spaced from adjacent portions of the at least one sealing strip. 
     
     
         7 . The turbine according to  claim 1 , wherein the at least one sealing strip comprises a plurality thereof having overlapping ends. 
     
     
         8 . The turbine according to  claim 7 , wherein each sealing strip carries a respective movable locking tang. 
     
     
         9 . The turbine according to  claim 1 , according to  claim 7  wherein the plurality of sealing strips comprises four 90° sealing strips. 
     
     
         10 . The turbine according to  claim 9 , wherein the at least one movable locking tang comprises a respective movable locking tang carried by each of the four 90° sealing strips. 
     
     
         11 . The turbine according to  claim 1 , wherein the at least one pair of adjacent disks further defines a disk cooling fluid chamber positioned radially inwardly from the sealing band and a blade cooling chamber positioned radially outwardly from the sealing band. 
     
     
         12 . A sealing band for a turbine including a plurality of successive stages each comprising a rotatable disk and blades carried thereby, at least one pair of adjacent rotatable disks defining an annular gap therebetween and having respective opposing sealing band receiving slots aligned with the annular gap, at least one of the rotatable disks having at least one notch therein coupled to the respective sealing band receiving slot, the sealing band for positioning in the opposing sealing band receiving slots to seal the corresponding annular gap, the sealing band comprising:
 at least one sealing strip; and   at least one movable locking tang carried by the at least one sealing strip for extending into the at least one notch to define an anti-rotational feature for the sealing band.   
     
     
         13 . The sealing band according to  claim 12 , wherein the at least one movable locking tang and the at least one sealing strip are integrally formed as a monolithic unit; and wherein said movable locking tang is bendable with respect to adjacent portions of the at least one sealing strip. 
     
     
         14 . The sealing band according to  claim 12 , wherein the at least one movable locking tang has a distal end being movable from a coplanar position relative to adjacent portions of the at least one sealing strip to a bent position extending radially inwardly from adjacent portions of the at least one sealing strip. 
     
     
         15 . The sealing band according to  claim 14 , wherein the distal end is flush with adjacent side edges of the at least one sealing strip when in the coplanar position. 
     
     
         16 . The sealing band according to  claim 14 , wherein the at least one sealing strip comprises a plurality thereof having overlapping ends. 
     
     
         17 . The sealing band according to  claim 16 , wherein each sealing strip carries a respective movable locking tang. 
     
     
         18 . A method for installing a sealing band in a turbine including a plurality of successive stages each comprising a rotatable disk and blades carried thereby, at least one pair of adjacent rotatable disks defining an annular gap therebetween and having respective opposing sealing band receiving slots aligned with the annular gap, at least one of the rotatable disks having at least one notch therein coupled to the respective sealing band receiving slot, the method comprising:
 positioning the sealing band in the opposing sealing band receiving slots to seal the corresponding annular gap, the sealing band comprising at least one sealing strip and at least one movable locking tang carried thereby; and   moving the at least one movable locking tang to extend into the at least one notch to define an anti-rotational feature for the sealing band.   
     
     
         19 . The method according to  claim 18 , wherein the at least one movable locking tang and the at least one sealing strip are integrally formed as a monolithic unit; and wherein moving comprises bending the at least one movable locking tang with respect to adjacent portions of the at least one sealing strip. 
     
     
         20 . The method according to  claim 18 , wherein moving comprises moving a distal end of the at least one movable locking tang from a coplanar position relative to adjacent portions of the at least one sealing strip to a bent position extending radially inwardly from adjacent portions of the at least one sealing strip. 
     
     
         21 . The method according to  claim 20 , wherein the distal end is flush with adjacent side edges of the at least one sealing strip when in the coplanar position. 
     
     
         22 . The method according to  claim 18 , wherein the at least one sealing strip comprises a plurality thereof; and wherein positioning the sealing band comprises overlapping ends of the plurality of sealing strips in the opposing sealing band receiving slots. 
     
     
         23 . The method according to  claim 22 , wherein each sealing strip carries a respective movable locking tang that is moved into a corresponding notch. 
     
     
         24 . The method according to  claim 22 , wherein positioning the sealing band and moving the at least one movable locking tang are performed without welding.