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US4021603A Expired / Lapsed US ⏱️ 0.0 years remaining

Roof for arc furnace

Assignee: IHI Corp
•
Filing: 1975-10-22
•
Granted: 1977-05-03
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Expires: 1995-10-22
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Abstract

Abstract A roof assembly for an arc furnace is disclosed in which a furnace roof ring and a plurality of roof units are assembled together to define a roof section frustoconical in cross section and with a roof top opening, and a roof top made of an electrically insulating refractory and provided with electrode holes closely fitted into the roof top opening. Each sectionalized roof unit comprises a main body cast from cast iron or copper, and a cooling coil embedded in the main body with end sections being extended out of the upper major upper surface of the main body so as to be used as a cooling water inlet and an outlet. In order to ensure the satisfactory high-temperature strength and thermal-shock resistance, the inner major surface of the main body directed toward the inside of the furnace is partially lined with the refractory or corrugated.

Inventors

  • 👤 Toshio Nanjyo
  • 👤 Masayuki Aoshika

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 13:41
CPC Classifications
F; F27; F27D; F27D1/00; F27D1/18; F27D1/1808; F27D1/1816

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 106 words
A roof assembly for an arc furnace comprising a roof ring made of metal and defining the outer periphery of the furnace roof assembly, and a plurality of unitary, sectionalized roof units asssembled together in said roof ring to define the furnace roof, each unit comprising a trapezoidal-shaped, cast metallic member having spaced-apart inner and outer arcuate surfaces, a cooling coil embedded in said member for receiving and discharging a cooling liquid, and the units being arranged with their sides in abutting relationship and with the outer arcuate surfaces engaging said roof ring, said units being in the form of a truncated cone and being self-supporting.
Claim 2
Dependent Claim 106 words
A roof assembly for an arc furnace comprising a roof ring made of metal and defining the outer periphery of the furnace roof assembly, and a plurality of unitary, sectionalized roof units asssembled together in said roof ring to define the furnace roof, each unit comprising a trapezoidal-shaped, cast metallic member having spaced-apart inner and outer arcuate surfaces, a cooling coil embedded in said member for receiving and discharging a cooling liquid, and the units being arranged with their sides in abutting relationship and with the outer arcuate surfaces engaging said roof ring, said units being in the form of a truncated cone and being self-supporting.
Claim 3
Dependent Claim 37 words
A roof assembly as set forth in claim 1 wherein the inner arcuate surfaces of the abutting roof units are shaped to define a substantially inverted truncated conical seat, and a roof top fitting into said seat.

References Cited (Backward Citations)

US3756172A Cited
US3829595A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-05-02 1980-11-01 1981-05-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-05-02 1984-11-01 1985-05-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-05-02 1988-11-01 1989-05-03 $7700.00 Window Closed / Lapsed

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