Methods of maintaining turbine discs to avert critical bucket attachment dovetail cracks

• Main Authors: WALSH JOHN, WILLIAMS ANDREW D, CALDER WILLIAM
• Format: Patent
• Language: English
• Published: 14.08.2012
• Subjects: BLASTING; COMBINED OPERATIONS; ENGINE PLANTS IN GENERAL; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HEATING; INDEXING SCHEME FOR ASPECTS RELATING TONON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES ORJET-PROPULSION PLANTS; INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUSSUBCLASSES OF CLASSES F01-F04; LIGHTING; MACHINE TOOLS; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; METAL-WORKING NOT OTHERWISE PROVIDED FOR; NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAMTURBINES; OTHER WORKING OF METAL; PERFORMING OPERATIONS; STEAM ENGINES; TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TRANSPORTING; UNIVERSAL MACHINE TOOLS; WEAPONS

Methods of to maintaining turbine discs prone to cracks in bucket attachment dovetails are disclosed. In one embodiment, wherein a turbine disc comprises a plurality of bucket attachment dovetail regions, one or more of the bucket attachment dovetail regions comprises a cooling slot, and each cooling slot comprises edges and adjacent surfaces, a method comprises inspecting the one or more of the bucket attachment dovetail regions comprising a cooling slot to confirm that each bucket attachment dovetail region meets predetermined minimum standards. The method further comprises blending the edges of the at least one of the cooling slots. The method further comprises polishing the edges of the at least one of the cooling slots. The method further comprises peening the edges of the at least one of the cooling slots. The method further comprises coating the edges and adjacent surfaces of at least one of the cooling slots.