Patent US3794445A successfully refreshed from Google Patents.
US3794445A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water turbine runner
Assignee: Hitachi Ltd
•
Filing: 1972-04-28
•
Granted: 1974-02-26
•
Expires: 1992-04-28
Abstract
Abstract A water turbine runner comprising a plurality of blades coaxially fixed to one axis each of said blades is composed of an iron-based material, wherein each blade is provided with a smooth surface weld metal on the surface where erosion due to cavitation liable to take place, said weld metal being made of an erosionresistant metal consisting essentially of up to 0.5 wt% of C, 10 to 30 wt% of Cr, 0.5 to 30 wt% of Co, up to 1 wt% of Si, up to 3 wt% of Mn, and the balance of Fe.
Inventors
- 👤 T Kobayashi
- 👤 K Watanabe
- 👤 K Saito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:26
CPC Classifications
F; F03; F03B; F03B3/00; F03B3/12; Y; Y02; Y02E; Y02E10/00; Y02E10/20
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
23 words
The water turbine runner of claim 1, wherein said weld metal contains less than 0.03 wt.% of P and S as inevitable impurities.
Claim 2
Dependent Claim
20 words
The water turbine runner of claim 1, wherein said weld metal contains from 0.17 wt.% to 1 wt.% of Si.
Claim 3
Dependent Claim
19 words
The water turbine runner of claim 3, wherein said weld metal contains 0.35 wt.% to 3 wt.% of Mn.
Claim 4
Dependent Claim
23 words
The water turbine runner of claim 1, wherein said weld metal contains Cr and Co in a total amount less than 26 wt.%.
Claim 5
Dependent Claim
109 words
A Pelton type water turbine runner comprising a plurality of buckets coaxially fixed to one axis, the bucket being composed of an iron-base material, each of said buckets being provided with a smoothed-surface weld metal formed only on the surface at the position where high speed water collides therewith and erosion due to cavitation takes place, said weld metal consisting essentially of 0.1 to 0.5 wt.% of C, 10 to 30 wt.% of Cr, 0.5 to 30 wt.% of Co, an effective amount for effecting deoxidation up to 1 wt.% of Si; an effective amount for effecting deoxidation up to 3 wt.% of Mn and the balance of Fe.
Claim 6
Dependent Claim
113 words
A Capron or Francis type water turbine runner comprising a plurality of blades coaxially fixed to one axis, the blades being composed of an iron-base material, each blade to which the high speed water collides being provided with a smoothed-surface weld metal only on a part of the surface of the blade at which erosion due to cavitation takes place, said weld metal consisting essentially of 0.1 to 0.5 wt.% of C, 10 to 30 wt.% of Cr, 0.5 to 30 wt.% of Co, an effective amount for effecting deoxidation up to 1 wt.% of Si, an effective amount for effecting deoxidation up to 3 wt.% of Mn and the balance of Fe.
Claim 7
Dependent Claim
103 words
A water turbine runner comprising a plurality of blades coaxially fixed to one axis, the blade being composed of an iron-base material, each of said blades being provided with smoothed-surface weld metal only on a part where cavitation erosion takes place, said weld metal consisting essentially of 0.1 to 0.5 wt.% of C, 10 to 30 wt.% of Cr, 0.5 to 30 wt.% of Co, 1 to 8 wt.% of Cu., an effective amount for effecting deoxidation up to 1 wt.% of Si, an effective amount for effecting deoxidation up to 3 wt.% of Mn and the balance of Fe and accompanying impurities.
Claim 8
Dependent Claim
106 words
A water turbine runner comprising a plurality of blades coaxially fixed to one axis, the blades being composed of an iron-base material, each of said blades being provided with smoothed-surface weld metal on a part of surface where cavitation-erosion takes place, said weld metal having a thickness of 3 to 7 mm. and consisting essentially of 0.1 to 0.5 wt.% of C, 10 to 30 wt.% of Cr, 0.5 to 30 wt.% of Co, an effective amount for effecting deoxidation up to 1 wt.% of Si, an effective amount for effecting deoxidation up to 3 wt.% of Mn, and the balance of Fe and accompanying impurities.
Claim 9
Dependent Claim
104 words
A water turbine runner comprising a plurality of blades coaxially fixed to one axis, the blades being composed of a steel containing 11 to 14 wt.% of chromium, each of said blades being provided with a weld metal on an only part of surface where cavitation-erosion takes place, said weld metal consisting essentially of 0.1 to 0.5 wt.% of C, 10 to 30 wt.% of Cr, 0.5 to 30 wt.% of Co, an effective amount for effecting deoxidation up to 1 wt.% of Si, an effective amount for effecting deoxidation up to 3 wt.% of Mn; and the balance of Fe and accompanying impurities.
Claim 10
Dependent Claim
19 words
The water turbine runner of claim 10, wherein said weld metal has a thickness of 3 to 7 mm.
Claim 11
Dependent Claim
102 words
A water turbine runner comprising a plurality of blades coaxially fixed to one axis, said blades being composed of an iron-base material, wherein each blade is provided with a smooth-surface weld metal formed only on the surface at the position where erosion due to cavitation takes place, said weld metal consisting of 0.1 to 0.5 wt.% of C, 10 to 30 wt.% of Cr, 0.5 to 30 wt.% of Co, an effective amount for effecting deoxidation up to 1 wt.% of Si, an effective amount for effecting deoxidation up to 3 wt.% of Mn and the balance of Fe and inevitable impurities.
Claim 12
Dependent Claim
23 words
The water turbine runner of claim 12, wherein said weld metal contains less than 0.03 wt.% of P and S as inevitable impurities.
Claim 13
Dependent Claim
20 words
The water turbine runner of claim 12, wherein said weld metal contains from 0.17 wt.% to 1 wt.% of Si.
Claim 14
Dependent Claim
20 words
The water turbine runner of claim 14, wherein the weld metal contains from 0.35 wt.% to 3 wt.% of Mn.
Claim 15
Dependent Claim
23 words
The water turbine runner of claim 12, wherein the weld metal contains Cr and Co in a total amount less than 26 wt.%
Claim 16
Dependent Claim
102 words
A water turbine runner comprising a plurality of blades coaxially fixed to one axis, the blade being composed of an iron-base material, each of said blades being provided with smoothed-surface weld metal only on a part where cavitation erosion takes place, said weld metal consisting of 0.1 to 0.5 wt.% of C, 10 to 30 wt.% of Cr, 0.5 to 30 wt.% of Co, 1 to 8 wt.% of Cu, an effective amount for effecting deoxidation up to 1 wt.% of Si, an effective amount for effecting deoxidation up to 3 wt.% of Mn, and the balance of Fe and accompanying impurities.
Claim 17
Dependent Claim
23 words
The water turbine runner of claim 17, wherein said weld metal contains less than 0.03 wt.% of P and S as accompanying impurities.
Claim 18
Dependent Claim
20 words
The water turbine runner of claim 17, wherein the weld metal contains from 0.17 wt.% to 1 wt.% of Si.
Claim 19
Dependent Claim
20 words
The water turbine runner of claim 19, wherein the weld metal contains from 0.35 wt.% to 3 wt.% of Mn.
Claim 20
Dependent Claim
23 words
The water turbine runner of claim 17, wherein said weld metal contains Cr and Co in a total amount less than 26 wt.%.
References Cited (Backward Citations)
US1357549A
Cited
US1150113A
Cited
US2201425A
Cited
US2272534A
Cited
US2624671A
Cited
GB728972A
Cited
US3293030A
Cited
US3564689A
Cited
US3650845A
Cited
US3561886A
Cited
US3661658A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-25 | 1977-08-27 | 1978-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-25 | 1981-08-27 | 1982-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-25 | 1985-08-27 | 1986-02-26 | $7700.00 | Window Closed / Lapsed |