ASSEMBLY OF BUCKET FOR TURBINE WHEEL WHEREIN DAMPER PIN IS ARRANGED BETWEEN ADJOINING BUCKETS OF TURBINE ROTOR

摘要

PURPOSE: An assembly of a bucket for a turbine wheel is provided to reduce vibration stress and to lengthen the life span of the bucket. CONSTITUTION: An assembly of a bucket(10) for a turbine wheel comprises a pair of adjoining buckets(12a) and a damper pin arranged between the adjoining buckets and a recessed part formed between the adjoining buckets. The bucket has a bucket airfoil(12), a platform(14), a shank(16), and a dovetail(18). The dovetail has a shape for fixing the bucket to the turbine wheel. The first bucket of the buckets has at least a first support part(24) extended in the circumferential direction via a peripheral edge of the platform of the first bucket from the side. The first support part has a support surface(26). The second bucket of the buckets is opened in the circumferential direction toward the first bucket. The second bucket has an undercut situated under the platform of the second bucket. The first bucket has a surface(20) adjacent to the support part and extended toward the radial outside. The radially extended surface and support surface of the first bucket constitute the recessed part between a pair of buckets situated under the second bucket together the slant surface of the undercut of the second bucket. The damper pin moves between a first position supported on the support surface in the recessed part to remove vibration action of the bucket, and a second position combined to the radially extended surface of the first bucket and the slant surface of the recessed part of the second bucket.