US5120197A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tip-shrouded blades and method of manufacture
Assignee: General Electric Co
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Filing: 1990-07-16
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Granted: 1992-06-09
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Expires: 2010-07-16
Abstract
Abstract Taught is an improved tip-shrouded blade and a method of manufacturing the same. In accordance with the present invention, the inventive blade comprises a blade including an airfoil having a residual compressive stress in areas thereof subject to high local stress.
Inventors
- 👤 Robert O. Brooks
- 👤 Eric A. Estill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:51
CPC Classifications
B; B23; B23P; B23P15/00; B23P15/02; F; F01; F01D; F01D5/00; F01D5/12; F01D5/14; F01D5/22; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49316; Y10T29/49336
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
83 words
A tip-shrouded blade consisting of a material having a known yield point and comprising: (a) an airfoil including an airfoil root and an airfoil tip, said airfoil including a residual compressive stress in selected areas created by twisting said blade in a substantially circumferential direction about a longitudinal axis of said blade past said known yield point of said material of said airfoil; (b) a tip shroud attached to said airfoil tip; and (c) means for attaching said airfoil root to a turbomachine.
Claim 2
Dependent Claim
83 words
A tip-shrouded blade consisting of a material having a known yield point and comprising: (a) an airfoil including an airfoil root and an airfoil tip, said airfoil including a residual compressive stress in selected areas created by twisting said blade in a substantially circumferential direction about a longitudinal axis of said blade past said known yield point of said material of said airfoil; (b) a tip shroud attached to said airfoil tip; and (c) means for attaching said airfoil root to a turbomachine.
Claim 3
Dependent Claim
31 words
The blade of claim 1 wherein said material is a nickel based alloy and wherein said blade is twisted at least two-tenths of one per cent past said known yield point.
Claim 4
Dependent Claim
35 words
The blade of claim 1 wherein said residual compressive stress is substantially localized within selected ones of a first region of said airfoil adjacent said airfoil root and a second region adjacent said airfoil tip.
Claim 5
Dependent Claim
30 words
The blade of claim 3 wherein said residual compressive stress is further localized within each of said first and second regions at the leading and trailing edges of said blade.
Claim 6
Dependent Claim
48 words
The blade of claim 1, wherein said turbomachine includes at least one row of a plurality of tip-shrouded blades attached circumferentially to a turbine rotor and wherein each of said tip shrouds is configured for a "Z" interlock with the tip shrouds of adjacent blades of the turbomachine.
Claim 7
Independent Claim
92 words
A method of manufacturing an improved tip-shrouded blade consisting of a material having a known yield point, said blade comprising: (a) an airfoil including an airfoil root and an airfoil tip; (b) a tip shroud attached to said airfoil tip; and (c) means for attaching said airfoil root to a turbomachine; wherein said method of manufacture comprises the step of: creating a residual compressive stress in selected areas of said airfoil by substantially circumferentially twisting said airfoil about a longitudinal axes of said airfoil past said known yield point of said airfoil.
Claim 8
Independent Claim
92 words
A method of manufacturing an improved tip-shrouded blade consisting of a material having a known yield point, said blade comprising: (a) an airfoil including an airfoil root and an airfoil tip; (b) a tip shroud attached to said airfoil tip; and (c) means for attaching said airfoil root to a turbomachine; wherein said method of manufacture comprises the step of: creating a residual compressive stress in selected areas of said airfoil by substantially circumferentially twisting said airfoil about a longitudinal axes of said airfoil past said known yield point of said airfoil.
Claim 9
Dependent Claim
29 words
The method of claim 6 wherein said material is a nickel-based alloy and said blade is twisted at least two-tenths of one per cent beyond said known yield pint.
Claim 10
Dependent Claim
31 words
The method of claim 6 wherein said selected areas of said blade includes a first region of said airfoil adjacent said airfoil root and a second region adjacent said airfoil tip.
Claim 11
Dependent Claim
30 words
The method of claim 8 wherein said residual compressive stress is further localized within each of said first and second regions at the leading and trailing edges of said blade.
Claim 12
Dependent Claim
48 words
The method of claim 6, wherein said turbomachine includes at least one row of a plurality of tip-shrouded blades attached circumferentially to a turbine rotor and wherein each of said tip shrouds is configured for a "Z" interlock with the tip shrouds of adjacent blades of the turbomachine.
Claim 13
Independent Claim
63 words
A method for manufacturing apparatus consisting of a substantially singular material having a known yield point, wherein said apparatus has an improved tolerance to the development of high local stresses in particular areas thereof, said method comprising the step of: creating a residual compressive stress of selected regions of said areas of said apparatus by stressing said selected regions beyond said yield point.
Claim 14
Independent Claim
63 words
A method for manufacturing apparatus consisting of a substantially singular material having a known yield point, wherein said apparatus has an improved tolerance to the development of high local stresses in particular areas thereof, said method comprising the step of: creating a residual compressive stress of selected regions of said areas of said apparatus by stressing said selected regions beyond said yield point.
References Cited (Backward Citations)
US1763256A
Cited
US2510734A
Cited
US3185441A
Cited
US3834833A
Cited
US4010531A
Cited
US4076455A
Cited
US4247254A
Cited
US4247259A
Cited
US4364160A
Cited
US4411597A
Cited
US4418455A
Cited
US4426867A
Cited
US4594761A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-06-09 | 1995-12-09 | 1996-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-06-09 | 1999-12-09 | 2000-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-06-09 | 2003-12-09 | 2004-06-09 | $7700.00 | Window Closed / Lapsed |