Patent US4897519A successfully refreshed from Google Patents.
US4897519A
Expired / Lapsed
US
⏱️ 0.0 years remaining
More creep resistant turbine rotor, and procedures for repear welding of low alloy ferrous turbine components
Assignee: Siemens Energy Inc
•
Filing: 1988-03-14
•
Granted: 1990-01-30
•
Expires: 2008-03-14
Abstract
Abstract A more creep resistant turbine rotor and novel methods for repairing worn surfaces of Cr-Mo-V steam turbine components are disclosed. These methods include specified alloy compositions and welding procedures that minimize weld stresses and cracking. These alloys exhibit improved creep and fatigue properties and are preferably deposited using a gas tungsten arc welding procedure. Bead sequencing, cooling side plates and the use of run-off tabs are also disclosed for minimizing welding defects in turbine rotors and discs.
Inventors
- 👤 Robert E. Clark
- 👤 Dennis R. Amos
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:32
CPC Classifications
B; B23; B23K; B23K35/00; B23K35/22; B23K35/24; B23K35/30; B23P; B23P6/00; B23P6/002; B23P6/007; B23K35/3053; B23K35/308; B23K9/00; B23K9/04; B23K9/044; B23K9/046; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49229; Y10T29/49231; Y10T29/49233; Y10T29/49316; Y10T29/49318
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
86 words
A method of repairing a worn surface of a ferrous steam turbine component having less than about 6% alloying ingredients including Cr, Mo and V, comprising: (a) providing a steam turbine component having a worn surface thereon; (b) depositing a ferrous alloy on said worn surface in a multipass buildup comprising at least two spaced apart weldments, said ferrous alloy comprising about 7.0% to 11.0% weight percent Cr and about 0.1% to 3.0% weight percent Mo; and (c) machining said deposited alloy to a desired shape.
Claim 2
Independent Claim
86 words
A method of repairing a worn surface of a ferrous steam turbine component having less than about 6% alloying ingredients including Cr, Mo and V, comprising: (a) providing a steam turbine component having a worn surface thereon; (b) depositing a ferrous alloy on said worn surface in a multipass buildup comprising at least two spaced apart weldments, said ferrous alloy comprising about 7.0% to 11.0% weight percent Cr and about 0.1% to 3.0% weight percent Mo; and (c) machining said deposited alloy to a desired shape.
Claim 3
Dependent Claim
101 words
The method of claim 1 wherein said depositing step comprises depositing a ferrous alloy consisting essentially of about 0.04 to 0.22 weight percent C, 0.15 to 1.0 weight percent Mn, 0.15 to 1.0 weight percent Si, 0.0 to 0.02 weight percent P, 0.0 to 0.16 weight percent S, 0.0 to 0.8 weight percent Ni, 4.00 to 19.0 weight percent Cr, 0.43 to 2.1 weight percent Mo, 0.09 to 0.5 weight percent V, 0.03 to 0.20 weight percent Nb, 0.0 to 0.08 weight percent Al, 0.0 to 0.20 weight percent Cu, 0.005 to 0.06 weight percent N, and the balance being Fe.
Claim 4
Dependent Claim
17 words
The method of claim 2 wherein said providing step provides a turbine component comprising a turbine disc.
Claim 5
Dependent Claim
18 words
The method of claim 3 wherein said depositing step comprises building up a worn surface of said disc.
Claim 6
Dependent Claim
101 words
The method of claim 1 wherein said depositing step comprises depositing a ferrous alloy consisting essentially of about 0.08 to 0.11 weight percent C, 0.30 to 0.50 weight percent Mn, 0.30 to 0.50 weight percent Si, 0.00 to 0.10 weight percent P, 0.00 to 0.008 weight percent S, 0.00 to 0.40 weight percent Ni, 8.00 to 9.50 weight percent Cr, 0.85 to 1.05 weight percent Mo, 0.18 to 0.25 weight percent V, 0.06 to 0.10 weight percent Nb, 0.00 to 0.04 weight percent Al, 0.00 to 0.10 weight percent Cu, 0.01 to 0.03 weight percent N, and the balance being Fe.
Claim 7
Dependent Claim
18 words
The method of claim 1 wherein said depositing step comprises welding said ferrous alloy to said worn surface.
Claim 8
Dependent Claim
12 words
The method of claim 6 wherein said welding step comprises plasma-arc welding.
Claim 9
Dependent Claim
14 words
The method of claim 6 wherein said welding step comprises gas tungsten arc welding.
Claim 10
Dependent Claim
23 words
The method of claim 6 further comprising preheating said steam turbine component to at least about 177° C. prior to said welding step.
Claim 11
Dependent Claim
27 words
The method of claim 1 wherein said depositing step comprises disposing a side plate on said turbine component for withdrawing heat at least during said depositing step.
Claim 12
Dependent Claim
18 words
The method of claim 10 wherein said disposing a side plate step selects a side plate comprising copper.
Claim 13
Dependent Claim
12 words
The method of claim 11 further comprising water cooling said side plate.
Claim 14
Dependent Claim
32 words
The method of claim 12 further comprising disposing said water cooled side plate along an edge of said worn surface, whereby said ferrous alloy is deposited on said water cooled side plate.
Claim 15
Dependent Claim
16 words
The method of claim 1 wherein said providing step selects a turbine component comprising a rotor.
Claim 16
Dependent Claim
29 words
The method of claim 1 further comprising heating said worn surface and said deposited alloy to relieve at least a portion of the stresses created by said depositing step.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-29 | 1993-07-31 | 1994-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-29 | 1997-07-31 | 1998-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-29 | 2001-07-31 | 2002-01-30 | $7700.00 | Window Closed / Lapsed |