US3558113A - Radiation shields for furnaces - Google Patents

Radiation shields for furnaces Download PDF

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Publication number
US3558113A
US3558113A US788195A US3558113DA US3558113A US 3558113 A US3558113 A US 3558113A US 788195 A US788195 A US 788195A US 3558113D A US3558113D A US 3558113DA US 3558113 A US3558113 A US 3558113A
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United States
Prior art keywords
furnace
radiation shield
ring members
free standing
frame member
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US788195A
Inventor
Gerolf Strohmeier
Alfred Pohler
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Schwarzkopf Technologies Corp
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Schwarzkopf Technologies Corp
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Filing date
Publication date
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Publication of US3558113A publication Critical patent/US3558113A/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L59/00—Thermal insulation in general
    • F16L59/08—Means for preventing radiation, e.g. with metal foil
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J6/00—Heat treatments such as Calcining; Fusing ; Pyrolysis
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/0006—Details, accessories not peculiar to any of the following furnaces
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L59/00—Thermal insulation in general
    • F16L59/06—Arrangements using an air layer or vacuum
    • F16L59/075—Arrangements using an air layer or vacuum the air layer or the vacuum being delimited by longitudinal channels distributed around the circumference of a tube
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D1/00—Casings; Linings; Walls; Roofs
    • F27D1/0003—Linings or walls
    • F27D1/0033—Linings or walls comprising heat shields, e.g. heat shieldsd
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D5/00—Supports, screens, or the like for the charge within the furnace
    • F27D5/0062—Shields for the charge

Definitions

  • Int Cl 263/50 ABSTRACT This invention relates to radiation shields for F23n 9/00, furnaces. Such shields are made of a removable ray protection element and a plurality of foil layers.
  • Radiation shields for furnaces usually consist of a plurality of concentric metal cylinders interconnected with spacers.
  • the cylinders when small enough, can be produced from a single sheet although for larger size cylinders several sheets have to be connected together by riveting or welding.
  • Such conventional radiation shields are expensive to produce and are also disadvantageous. Thermal tensions form in the radiation shield resulting in deformation and cracking of the cylinder metal.
  • such materials as molybdenum and tungsten when present as the metallic component of radiation shields, recrystallize at high working temperatures and ultimately become very brittle and hence ineffective.
  • Such fixed radiation shields also develop rough inner surfaces reducing the desired reflection.
  • the radiation shields due to the concentric metal cylinders, are very heavy and cumbersome.
  • Radiation shields made of multilayers of metal foil are found to be unsatisfactory since they become brittle when exposed to the heat zone of the furnace and, in addition, the surface layers of the foil tend to adhere and become welded together thereby losing efficiency.
  • radiation shields contain a frame of a high temperature resistance material which is covered on the side of exposure to rays with removable metallic ray protection elements and on the cooler side, the side away from the rays, with several spaced apart layers of metal foil.
  • the metallic ray protection elements are removable they can easily be removed and new elements inserted when necessary rather than having to replace the entire shield.
  • the frame itself is protected from the highest furnace temperatures and hence need not be replaced, and the foil layers, while not exposed to the highest furnace temperatures and therefore not subjected to the extreme conditions that previously caused breakdown of foil parts, nevertheless operate, to produce their shielding effect in a very satisfactory manner.
  • the foil layers are arranged on a part of the radiation shield where they are exposed to relatively lower temperature.
  • the metallic ray protection elements are made of high melting point materials having satisfactory radiation shielding properties in accordance with prior art techniques.
  • the metal should have a melting point in excess of about 2500 C.
  • Such materials as tungsten, molybdenum and tantalum are particularly useful. Ceramic materials can also be used where desired.
  • the frame should be made of suitable high temperature resistance materials as well.
  • the foil components can be any of the foil materials known to the art for use in radiation shielding.
  • FIGS. 1 and 2 illustrate the frame of the radiation shield
  • FIG. 3 is a cross-sectional view of the complete radiation shield showing the frame, shielding elements and foil layers in lace;
  • FIGS. 4, 5 and 6 are sectional views of a shielding element;
  • FIG. 7 illustrates the arrangement of the radiation shield elements on a frame body with even surface.
  • the frame can be fonned of a corrugated sheet of high melting metal.
  • the shape of the frame is circular as shown in FIG. I, while in FIG. 2, the shape is shown to be generally square. The exact shape of the frame is relatively unimportant.
  • the frame can be formed of a solid material or it can be made of wound or interwoven wire.
  • the frame I is first formed as in the circular shape shown in FIG. 1.
  • wire rings 2 and 3 are provided.
  • the wire rings can be anchored either through holes in frame I or secured through the use of bolts or eyelets 4.
  • Several wire rings can be-arranged one over the other.
  • the heating shield elements 5 are attached on the inner wire ring 2.
  • the radiation shield elements need not be in one piece and preferably will not be, to insure ease of removal.
  • a suitable means of attaching theradiation shield elements 5 is shown in FIGS. 4, 5 and 6.
  • Each of the separate radiation shield elements 5 is provided with lugs 6 which can be at tached to the wire rings 2. As can be seen, the individual elements 5 can easily be replaced and removed when desired.
  • the radiation shield elements 5 are arranged in a fashion similar to shingles on a roof such that each overlaps the next and covers the inner side of the frame completely.
  • a plurality of layers of foil 7 are imposed over the frame I and can be attached through the use of wire connectors or other devices to the wire rings 3.
  • the radiation shields can be covered with a metal sheet coating 8.
  • a radiation shield for the attenuation of radiation emitted from furnaces comprising:
  • a free standing frame member that completely encircles said furnace; continuous inner ring members affixed to the inner portion of said frame structure to structurally reinforce said frame structure, said inner ring members completely encircling said furnace;
  • Continuous outer ring members affixed to the outer portion of said frame structure to structurally reinforce said frame structure, said outer ring members completely encircling said furnace; shielding elements being rectangular in shape and having a concaved curvature removably affixed to and in a spa cial relationship from said inner ring members so as to be positioned between said free standing frame member and said furnace with the concavity exposed to said furnace, said shielding elements overlapping with respect to each other so as to provide a continuous shielding surface that completely encircles said furnace; and foil layers removably affixed to and in a spacial relationship from said outer ring member, said foil layers completely encircling said furnace.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Furnace Housings, Linings, Walls, And Ceilings (AREA)

Abstract

This invention relates to radiation shields for furnaces. Such shields are made of a removable ray protection element and a plurality of foil layers.

Description

United States Patent [72] Inventors GerolfStrohmeier; [50] Field of 263/50; Alfred Pohler, Reutte, Austria 126/202; 250/108 X XX 05500 5 55 3 33 6 66 2 22 m S "mm m .l T u H P m. .m d m nnnun n T "uh a M u n m A .m h n 6 mt m m mm C e m 0 SE r m MU Tamas m m em nm fTc Sa .mSmvu m g\ BD 8.110 .16 MTLCBmm i M56770 J N66666 99999 u 1111] ng r 5 567 mo mM 033 5 69043 ,529 W 55776 am I 88 25 m 6 J nn B. 33333 PA n .m m w 0 C t k m 0 m Y n W e M v s mv I 67 m.Nm 990 m mu mm flw MSZMYMiM U mmm u 7 J mNaJAA 0. de N w w N m m P i m n AFPA P 11]] 1]] I253 23 2247 333 [iii [[I.
[54] RADIATION SHIELDS FOR FURNACES 5 Claims, 7 Drawing Figs.
[51] Int Cl 263/50 ABSTRACT: This invention relates to radiation shields for F23n 9/00, furnaces. Such shields are made of a removable ray protection element and a plurality of foil layers.
PATENTEU JAN26 ISII 3558.113
sum 1 [IF 2 FIG.|
' amou- SIROHME/ER- Fl 6. 2
A4 FRED Pal/L 52 RADIATION SHIELDS FOR FURNACES Radiation shields for furnaces usually consist of a plurality of concentric metal cylinders interconnected with spacers. The cylinders. when small enough, can be produced from a single sheet although for larger size cylinders several sheets have to be connected together by riveting or welding. Such conventional radiation shields are expensive to produce and are also disadvantageous. Thermal tensions form in the radiation shield resulting in deformation and cracking of the cylinder metal. In addition, such materials as molybdenum and tungsten, when present as the metallic component of radiation shields, recrystallize at high working temperatures and ultimately become very brittle and hence ineffective. Such fixed radiation shields also develop rough inner surfaces reducing the desired reflection. In addition, the radiation shields, due to the concentric metal cylinders, are very heavy and cumbersome.
Radiation shields made of multilayers of metal foil are found to be unsatisfactory since they become brittle when exposed to the heat zone of the furnace and, in addition, the surface layers of the foil tend to adhere and become welded together thereby losing efficiency.
The present invention does not suffer from the disadvantages of the prior, art system. In accordance with the present invention, radiation shields contain a frame of a high temperature resistance material which is covered on the side of exposure to rays with removable metallic ray protection elements and on the cooler side, the side away from the rays, with several spaced apart layers of metal foil.
Since the metallic ray protection elements are removable they can easily be removed and new elements inserted when necessary rather than having to replace the entire shield. The frame itself is protected from the highest furnace temperatures and hence need not be replaced, and the foil layers, while not exposed to the highest furnace temperatures and therefore not subjected to the extreme conditions that previously caused breakdown of foil parts, nevertheless operate, to produce their shielding effect in a very satisfactory manner. The foil layers are arranged on a part of the radiation shield where they are exposed to relatively lower temperature.
The metallic ray protection elements are made of high melting point materials having satisfactory radiation shielding properties in accordance with prior art techniques. Preferably the metal should have a melting point in excess of about 2500 C. Such materials as tungsten, molybdenum and tantalum are particularly useful. Ceramic materials can also be used where desired.
The frame should be made of suitable high temperature resistance materials as well.
The foil components can be any of the foil materials known to the art for use in radiation shielding.
The invention is further illustrated by reference to the drawings:
FIGS. 1 and 2 illustrate the frame of the radiation shield;
FIG. 3 is a cross-sectional view of the complete radiation shield showing the frame, shielding elements and foil layers in lace; p FIGS. 4, 5 and 6 are sectional views of a shielding element; and
FIG. 7 illustrates the arrangement of the radiation shield elements on a frame body with even surface.
As shown in FIGS. 1 and 2, the frame can be fonned of a corrugated sheet of high melting metal. The shape of the frame is circular as shown in FIG. I, while in FIG. 2, the shape is shown to be generally square. The exact shape of the frame is relatively unimportant. The frame can be formed of a solid material or it can be made of wound or interwoven wire.
As shown in FIG. 3, the frame I is first formed as in the circular shape shown in FIG. 1. To stabilize the frame and to com nect it with the other parts of the radiation shield. wire rings 2 and 3 are provided. The wire rings can be anchored either through holes in frame I or secured through the use of bolts or eyelets 4. Several wire rings can be-arranged one over the other.
On the inner wire ring 2, the heating shield elements 5 are attached. The radiation shield elements need not be in one piece and preferably will not be, to insure ease of removal. A suitable means of attaching theradiation shield elements 5 is shown in FIGS. 4, 5 and 6. Each of the separate radiation shield elements 5 is provided with lugs 6 which can be at tached to the wire rings 2. As can be seen, the individual elements 5 can easily be replaced and removed when desired.
The radiation shield elements 5 are arranged in a fashion similar to shingles on a roof such that each overlaps the next and covers the inner side of the frame completely.
A plurality of layers of foil 7 are imposed over the frame I and can be attached through the use of wire connectors or other devices to the wire rings 3. To protect the foil from physical harm, the radiation shields can be covered with a metal sheet coating 8.
It will be easily understood that other variations of this basic concept can be made and consequently it is not intended that *this invention be limited by the specific embodiments disclosed in the drawings.
We claim:
I. A radiation shield for the attenuation of radiation emitted from furnaces comprising:
a. a free standing frame member that completely encircles said furnace; continuous inner ring members affixed to the inner portion of said frame structure to structurally reinforce said frame structure, said inner ring members completely encircling said furnace;
. Continuous outer ring members affixed to the outer portion of said frame structure to structurally reinforce said frame structure, said outer ring members completely encircling said furnace; shielding elements being rectangular in shape and having a concaved curvature removably affixed to and in a spa cial relationship from said inner ring members so as to be positioned between said free standing frame member and said furnace with the concavity exposed to said furnace, said shielding elements overlapping with respect to each other so as to provide a continuous shielding surface that completely encircles said furnace; and foil layers removably affixed to and in a spacial relationship from said outer ring member, said foil layers completely encircling said furnace.
2. A radiation shield as described in claim I wherein said shielding elements act as a thermal absorbing barrier between said furnace and said foil layers.
3. A radiation shield as described in claim 2 wherein said free standing frame member is formed to define a corrugated pattern which closes upon itself.
4. A radiation shield as described in claim 3 wherein said free standing frame member defines a rectangular cross section.
5. A radiation shield as described in claim 3 wherein said free standing frame member defines a circular cross section.
mg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent: No. 3,558,113 Dated January 26, 1971 Inventor(a) Gerolf Strohmeier and Alfred Pohler It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:
an the first page, under "Assignee", the statement "a corpo'. of New York" should read a corporation of Maryland Signed and sealed this 21st day of September 1971.
(SEAL) Attest:
EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Acting Commissioner of Patem

Claims (5)

1. A radiation shield for the attenuation of radiation emitted from furnaces comprising: a. a free standing frame member that completely encircles said furnace; b. continuous inner ring members affixed to the inner portion of said frame structure to structurally reinforce said frame structure, said inner ring members completely encircling said furnace; c. Continuous outer ring members affixed to the outer portion of said frame structure to structurally reinforce said frame structure, said outer ring members completely encircling said furnace; d. shielding elements being rectangular in shape and having a concaved curvature removably affixed to and in a spacial relationship from said inner ring members so as to be positioned between said free standing frame member and said furnace with the concavity exposed to said furnace, said shielding elements overlapping with respect to each other so as to provide a continuous shielding surface that completely encircles said furnace; and e. foil layers removably affixed to and in a spacial relationship from said outer ring member, said foil layers completely encircling said furnace.
2. A radiation shield as described in claim 1 wherein said shielding elements act as a thermal absorbing barrier between said furnace and said foil layers.
3. A radiation shield as described in claim 2 wherein said free standing frame member is formed to define a corrugated pattern which closes upon itself.
4. A radiation shield as described in claim 3 wherein said free standing frame member defines a rectangular cross section.
5. A radiation shield as described in claim 3 wherein said free standing frame member defines a circular cross section.
US788195A 1968-01-05 1968-12-31 Radiation shields for furnaces Expired - Lifetime US3558113A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
AT12268A AT279190B (en) 1968-01-05 1968-01-05 Blast protection body for high temperature furnaces

Publications (1)

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US3558113A true US3558113A (en) 1971-01-26

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US788195A Expired - Lifetime US3558113A (en) 1968-01-05 1968-12-31 Radiation shields for furnaces

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US (1) US3558113A (en)
AT (1) AT279190B (en)
CH (1) CH499077A (en)
DE (1) DE1816789B1 (en)
FR (1) FR1597343A (en)
GB (1) GB1196070A (en)
NL (1) NL139387B (en)
SE (1) SE339289B (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4024338A (en) * 1973-11-17 1977-05-17 Laszlo Kortvelyessy High temperature heat insulation
EP0609492A1 (en) * 1993-01-30 1994-08-10 Ipsen Industries International Gesellschaft Mit Beschränkter Haftung Holder plate for the partial heat treatment of articles
US20080131684A1 (en) * 2005-01-10 2008-06-05 Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.V. Thermal Radiation Shield For Vacuum And Protective Atmosphere Furnaces
CN113330265A (en) * 2018-12-10 2021-08-31 普兰西股份有限公司 Shielding of high temperature furnace

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3185460A (en) * 1963-08-15 1965-05-25 Pacific Scientific Co Vacuum furnace
US3285593A (en) * 1964-09-04 1966-11-15 Gen Electric Furnace heat shield
US3317203A (en) * 1963-10-28 1967-05-02 Union Carbide Corp Radiation shield for induction furnace
US3327041A (en) * 1964-04-30 1967-06-20 Sylvania Electric Prod Radiant heat reflecting device
US3456935A (en) * 1967-09-20 1969-07-22 Alco Standard Corp Heat treating furnace with shielding packs

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3185460A (en) * 1963-08-15 1965-05-25 Pacific Scientific Co Vacuum furnace
US3317203A (en) * 1963-10-28 1967-05-02 Union Carbide Corp Radiation shield for induction furnace
US3327041A (en) * 1964-04-30 1967-06-20 Sylvania Electric Prod Radiant heat reflecting device
US3285593A (en) * 1964-09-04 1966-11-15 Gen Electric Furnace heat shield
US3456935A (en) * 1967-09-20 1969-07-22 Alco Standard Corp Heat treating furnace with shielding packs

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4024338A (en) * 1973-11-17 1977-05-17 Laszlo Kortvelyessy High temperature heat insulation
EP0609492A1 (en) * 1993-01-30 1994-08-10 Ipsen Industries International Gesellschaft Mit Beschränkter Haftung Holder plate for the partial heat treatment of articles
US5417567A (en) * 1993-01-30 1995-05-23 Ipsen Industries International Gesellschaft Mit Beschrankter Haftung Holder means for the partial thermal treatment of workpieces
US20080131684A1 (en) * 2005-01-10 2008-06-05 Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.V. Thermal Radiation Shield For Vacuum And Protective Atmosphere Furnaces
CN113330265A (en) * 2018-12-10 2021-08-31 普兰西股份有限公司 Shielding of high temperature furnace
CN113330265B (en) * 2018-12-10 2023-07-28 普兰西股份有限公司 Shielding of high temperature furnace
US12098885B2 (en) 2018-12-10 2024-09-24 Plansee Se Shielding for a high-temperature furnace

Also Published As

Publication number Publication date
GB1196070A (en) 1970-06-24
DE1816789B1 (en) 1969-10-16
FR1597343A (en) 1970-06-22
CH499077A (en) 1970-11-15
SE339289B (en) 1971-10-04
NL139387B (en) 1973-07-16
NL6817860A (en) 1969-07-08
AT279190B (en) 1970-02-25

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