Fixture and method for installing turbine buckets

Patent metadata

Field	Value
Publication number	US-2016201556-A1
Application number	US-201514594379-A
Country	US
Kind code	A1
Filing date	Jan 12, 2015
Priority date	Jan 12, 2015
Publication date	Jul 14, 2016
Grant date	—

Abstract

A fixture and method for installing turbine buckets is disclosed. The fixture is adapted for mounting a plurality of turbine buckets with dovetails to a rotor wheel of a turbomachine that is separated from an adjacent rotor wheel by a spacer wheel, the rotor wheel and the spacer wheel each having a plurality of circumferentially aligned dovetail slots, the fixture includes: a turbine bucket holder having a dovetail that is configured to engage with one of the dovetail slots of the spacer wheel. The profile of a bucket holder dovetail slot substantially aligns the dovetail of the turbine bucket with a dovetail slot of the rotor wheel for at least partial transfer of a turbine bucket thereto.

First claim

What is claimed is:

1 . A fixture adapted for mounting a plurality of turbine buckets with dovetails to a rotor wheel of a turbomachine that is separated from an adjacent rotor wheel by a spacer wheel, the rotor wheel and the spacer wheel each having a plurality of circumferentially aligned dovetail slots, the fixture comprising:
a turbine bucket holder having a dovetail that is configured to engage with one of the dovetail slots of the spacer wheel, wherein the turbine bucket holder defines a bucket holder dovetail slot having a profile that is configured to receive and secure therein a dovetail of one of the turbine buckets, wherein the profile of the bucket holder dovetail slot substantially aligns the dovetail of the turbine bucket with a dovetail slot of the rotor wheel for at least partial transfer thereto from the spacer wheel, wherein the dovetail of the turbine bucket substantially aligns with a dovetail slot of the rotor wheel upon being secured in the bucket holder dovetail slot, a sidewall of the turbine bucket holder cooperatively engages a sidewall of a circumferentially adjacent turbine bucket holder, and wherein the dovetail of the turbine bucket is slidably removable from the bucket holder dovetail slot and guided for insertion into the dovetail slot of the rotor wheel.

2 . The fixture of claim 1 , further comprising a plurality of connected turbine bucket holders each having a dovetail that is configured to engage with one of the dovetail slots of the spacer wheel, wherein a sidewall of each pair of adjacent turbine bucket holders in the plurality engages cooperatively to form a plurality of bucket holder dovetail slots spaced circumferentially about a radially outer periphery of the spacer wheel, each bucket holder dovetail slot having a profile that is configured to receive a dovetail of one of the turbine buckets.

3 . The fixture of claim 1 , further comprising a retention device coupled to the turbine bucket holder for securing the bucket holder dovetail slot to the spacer wheel.

4 . The fixture of claim 1 , wherein the turbine bucket holder comprises a plurality of independent segments configured to engage at least one other independent segment at a respective surface thereof to form a profile of the turbine bucket holder.

5 . The fixture of claim 1 , wherein the turbine bucket holder is composed at least partially of one of a plastic and a metal.

6 . The fixture of claim 1 , wherein the profile of the bucket holder dovetail slot comprises a fir tree shape having a plurality of hooks interspersed with a plurality of necks that engage with the dovetail, each of the plurality of hooks having a substantially planar contact surface that engages with a dovetail of a turbine bucket.

7 . The fixture of claim 1 , the bucket holder dovetail slot includes a non-contacting portion that is separated from the dovetail of the turbine bucket upon the turbine bucket holder engaging with the dovetail of the turbine bucket, the non-contacting portion defining one of a window space and a pocket that protects a portion of the dovetail slot of the turbine bucket holder.

8 . The fixture of claim 1 , wherein the turbine bucket holder includes one of an offset differential and an interlocking fixture for engaging a complementary dovetail slot of the spacer wheel.

9 . The fixture of claim 1 , wherein the turbine bucket holder includes chamfered tip edges.

10 . A fixture for mounting a plurality of turbine buckets with dovetails to a rotor wheel of a turbomachine having a plurality of circumferentially aligned dovetail slots, the fixture comprising:
a spacer wheel, separating the rotor wheel from an adjacent rotor wheel, having a plurality of circumferentially aligned dovetail slots; a plurality of turbine bucket holders each having a dovetail that is configured to engage with one of the dovetail slots of the spacer wheel, wherein each of the plurality of turbine bucket holders includes a dovetail slot having a profile configured to secure therein a dovetail of one of the turbine buckets, wherein each profile of a bucket holder dovetail slot substantially aligns a dovetail of a turbine bucket with one dovetail slot of the rotor wheel for at least partial transfer thereto, wherein the dovetail of each turbine bucket aligns with a dovetail slot of the rotor wheel upon being secured in a bucket holder dovetail slot, and wherein essentially all dovetails of the turbine buckets are adapted to be slidably removed from a bucket holder dovetail slot and guided for insertion into one of the dovetail slots of the rotor wheel.

11 . The fixture of claim 10 , wherein one of the plurality of turbine bucket holders comprises a plurality of independent segments configured to engage at least one other independent segment at a respective surface thereof to form a profile of the turbine bucket holder.

12 . The fixture of claim 10 , further comprising a plurality of retention devices coupled to one of the spacer wheel and one the turbine bucket holders of the plurality, wherein each of the plurality of retention devices secures a turbine bucket holder to the spacer wheel.

13 . The fixture of claim 10 , wherein each profile of a bucket holder dovetail slot includes a window space that provides a view of a dovetail slot of the rotor wheel upon securing a dovetail of the turbine bucket therein.

14 . The fixture of claim 10 , wherein each profile of a bucket holder dovetail slot comprises a fir tree shape having a plurality of hooks interspersed with a plurality of necks that engage with a dovetail of one of the turbine buckets, each of the plurality of hooks having a substantially planar contact surface that engages with a dovetail of one of the turbine buckets.

15 . The fixture of claim 10 , wherein the turbine bucket holder includes a portion that is separated from a dovetail of the turbine bucket upon the turbine bucket holder engaging with a dovetail of the turbine bucket, thereby defining a pocket that protects a portion of the dovetail slot of the turbine bucket holder.

16 . A method for mounting a plurality of turbine buckets having dovetails on a rotor wheel having a plurality of dovetail slots complementary to one of the dovetails of the turbine buckets, the method comprising:
inserting a plurality of turbine bucket holders in a spacer wheel to form a plurality of bucket holder dovetail slots; loading dovetails of the plurality of turbine buckets into a corresponding one of the plurality of bucket holder dovetail slots, the spacer wheel including a plurality of circumferentially aligned dovetail slots and being mounted on a rotor shaft on one side of the rotor wheel, wherein each turbine bucket holder engages cooperatively within a dovetail slot of the spacer wheel and includes one of the plurality of bucket holder dovetail slots dimensioned to secure therein a dovetail of one of the turbine buckets; aligning each bucket holder dovetail slot of the spacer wheel that is loaded with a turbine bucket with one of the dovetail slots of the rotor wheel; and at least partially transferring each of the turbine buckets from the bucket holder dovetail slot to an aligned dovetail slot of the rotor wheel.

17 . The method according to claim 16 , further comprising securing each of the turbine bucket holders to the spacer wheel before the loading of the plurality of the dovetails of the turbine buckets.

18 . The method according to 16 , further comprising removing the turbine bucket holders from the corresponding dovetail slots of the spacer wheel after the turbine

Assignees

• Gen Electric

Inventors

• Kolvick Sandra Beverly
• Bruce Kevin Leon
• Ferslew Matthew Ryan
• Hanson Stuart Craig
• Merlau Thomas Michael
• Oden Joshua Michael
• Penny Christopher Michael

Classifications

• F01D5/32 Primary

  Locking, e.g. by final locking blades or keys · CPC title

• F01D25/285 Primary

  Temporary support structures, e.g. for testing, assembling, installing, repairing; Assembly methods using such structures · CPC title

• F05D2230/64

  using positioning or alignment devices for aligning or centring, e.g. pins · CPC title

• F05D2230/68

  using auxiliary equipment for lifting or holding · CPC title

• F02C1/00 Primary

  Gas-turbine plants characterised by the use of hot gases or unheated pressurised gases, as the working fluid (by the use of combustion products F02C3/00, F02C5/00) · CPC title