US3781002A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dual coaxial tuyeres
Assignee: Centre de Recherches Metallurgiques CRM ASBL
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Filing: 1972-11-17
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Granted: 1973-12-25
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Expires: 1992-11-17
Abstract
Abstract A dual coaxial duct tuyere for blowing oxygen and a protective fluid through the bottom of a metallurgical convertor, the outer duct being of a cylindrical shape and of dimensions adapted to receive the inner duct which has a circular passage coaxial with the outer cylinder and an external configuration comprised of at least six straight sides connected to each other by short arcuate sections, the length of each arcuate section being less than onethird the length of the straight sides.
Inventors
- 👤 C Courard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:19
CPC Classifications
C; C21; C21C; C21C5/00; C21C5/28; C21C5/42; C21C5/46; C21C5/48
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
109 words
A dual, coaxial duct tuyere, particularly for use in metallurgical convertors, comprising an outer duct and an inner duct coaxial therewith, the outer contour of the inner duct cross-section comprising at least six substantially rectilinear segments uniformly arrayed along the periphery of said crosssection, said segments in succession being connected to each other by arcs of a length less than the lengths of said substantially rectilinear segments on either side of said arcs, the geometric envelope of said arcs being such that it may fit into the inner contour of said peripheral duct within the clearance required for inserting the inner duct into the outer duct without undue friction.
Claim 2
Dependent Claim
109 words
A dual, coaxial duct tuyere, particularly for use in metallurgical convertors, comprising an outer duct and an inner duct coaxial therewith, the outer contour of the inner duct cross-section comprising at least six substantially rectilinear segments uniformly arrayed along the periphery of said crosssection, said segments in succession being connected to each other by arcs of a length less than the lengths of said substantially rectilinear segments on either side of said arcs, the geometric envelope of said arcs being such that it may fit into the inner contour of said peripheral duct within the clearance required for inserting the inner duct into the outer duct without undue friction.
Claim 3
Dependent Claim
41 words
A tuyere according to claim 1, thus characterized that the outer contour of the inner duct cross-section comprises eight substantially rectilinear segments connected to each other by arcs joining the end of one segment to an end of a succeeding segment.
Claim 4
Dependent Claim
23 words
A tuyere according to claim 1, wherein the ratio of the length of each segment to the length of each arc exCeeds two.
Claim 5
Dependent Claim
19 words
A tuyere according to claim 1, wherein the outer duct is made of a stainless or refractory steel tube.
Claim 6
Dependent Claim
21 words
A tuyere according to claim 1, wherein the inner duct is made of a copper tube and preferably of annealed copper.
Claim 7
Dependent Claim
14 words
A convertor bottom provided with a plurality of tuyeres constructed according to claim 1.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-24 | 1977-06-25 | 1977-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-24 | 1981-06-25 | 1981-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-24 | 1985-06-25 | 1985-12-25 | $7700.00 | Window Closed / Lapsed |