GB1095376A - - Google Patents

Abstract

1, 095,376. Turbines; axial flow compressors. WESTINGHOUSE ELECTRIC CORPORATION. June 8, 1966 [June 24, 1965], No.25456/66. Headings F1C and F1T. An axial flow multi-stage gas turbine has an outer casing divided into upper and lower half portions 21a, 21b respectively along a horizontal axial plane P. Stationary shroud rings 34, Fig. 2, are mounted inwardly of the outer casing between adjacent stator blade shroud rings 29 by means of grooved retainer rings 36. Each shroud ring 34 is divided into two halves 34a, 34b, Fig. 3, of slightly less than 180‹ angular extent so that the facing ends 53a, 53b are spaced apart. In order to seal the space 54 between the facing ends whilst permitting thermal expansion of the ring halves, upper and lower arcuate sealing blocks 55a, 55b are mounted in the space by dowels 59. The plane faces 56 of the blocks abut in the dividing plane P and resilient sealing strips 64a, 64b are mounted in grooves in the respective facing surfaces of the blocks and ring halves. The space between the diametrically opposite ends of the ring halves is sealed in the same manner. Spaces 65a, 65b permit the axial passage of coolant air supplied to the interior of the outer casing through a pipe 50, plates 68a, 68b being provided to throttle the coolant flow. Each stator blade shroud ring 29 is also divided into upper and lower halves (29a, 29b), Fig. 5 (not shown) of less than 180‹ but of greater angular extent than the halves 34a, 34b, and supported by the retainer rings 36. The space between the facing ends (70a, 70b) of the halves (29a, 29b) is sealed by a pair of abutting sealing blocks (75) screwed (at 72) to the adjacent retainer rings 36 and having sealing flanges (77). Each retainer ring 36 is also divided into segments of less than 180‹ in a manner similar to that already described, Fig. 4 (not shown). The shroud rings 29, 34 are locked against circumferential movement by bolts 44, 46, respectively, engaging lugs on the rings. The mounting and sealing construction of the rings is applicable also to axial flow compressors.