US3879167A - Non-warping heat shield - Google Patents

Non-warping heat shield Download PDF

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Publication number
US3879167A
US3879167A US461814A US46181474A US3879167A US 3879167 A US3879167 A US 3879167A US 461814 A US461814 A US 461814A US 46181474 A US46181474 A US 46181474A US 3879167 A US3879167 A US 3879167A
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United States
Prior art keywords
plates
heat
heat shield
treatment
central opening
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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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US461814A
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English (en)
Inventor
Luca Norman C De
Eugene A Mizikar
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Jones and Laughlin Steel Inc
Ltv Steel Co Inc
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Jones and Laughlin Steel Corp
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Application filed by Jones and Laughlin Steel Corp filed Critical Jones and Laughlin Steel Corp
Priority to US461814A priority Critical patent/US3879167A/en
Priority to AU79549/75A priority patent/AU482155B2/en
Priority to NL7503677A priority patent/NL7503677A/xx
Priority to FR7510211A priority patent/FR2268081B1/fr
Priority to IT22100/75A priority patent/IT1034923B/it
Priority to DE19752515264 priority patent/DE2515264A1/de
Priority to CA224,243A priority patent/CA1035946A/en
Priority to GB15940/75A priority patent/GB1496394A/en
Priority to JP50046930A priority patent/JPS50145308A/ja
Application granted granted Critical
Publication of US3879167A publication Critical patent/US3879167A/en
Assigned to JONES & LAUGHLIN STEEL, INCORPORATED reassignment JONES & LAUGHLIN STEEL, INCORPORATED MERGER (SEE DOCUMENT FOR DETAILS). , DELAWARE, EFFECTIVE JUNE 22, 1981. Assignors: JONES & LAUGHLIN STEEL CORPORATION, A CORP. OF PA., NEW J&L STEEL CORPRATION, A CORP. OF DE., (CHANGED TO), YOUNGTOWN SHEET & TUBE COMPANY, A CORP. OF OH. (MERGED INTO)
Assigned to LTV STEEL COMPANY, INC., reassignment LTV STEEL COMPANY, INC., MERGER AND CHANGE OF NAME EFFECTIVE DECEMBER 19, 1984, (NEW JERSEY) Assignors: JONES & LAUGHLIN STEEL, INCORPORATED, A DE. CORP. (INTO), REPUBLIC STEEL CORPORATION, A NJ CORP. (CHANGEDTO)
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • 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
    • C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
    • C21D9/54—Furnaces for treating strips or wire
    • C21D9/663—Bell-type furnaces
    • C21D9/673—Details, accessories, or equipment peculiar to bell-type furnaces

Definitions

  • ABSTRACT The degree of localized overheating and temperature non-uniformity of coils encountered during batch heat-treatment processes is minimized through use of an insulated heat shield assembly having a central opening.
  • the dimensionally stable heat shield is constructed so as to be resistant to warpage during the heat-treating process.
  • Our invention generally relates to an insulated heat shield which is useful in obtaining improved temperature uniformity between the various stacked coils during batch coil heat-treatment.
  • the heat shield serves to suppress radiant heat energy and to limit convected heat energy transmitted to the top surface of the top coil in batch heabtreating furnaces of conventional construction.
  • the heat shield is placed on the top coil during the process so as to prevent the top surface of the top coil from locally overheating as a result of inherent furnace conditions.
  • Non-uniform heating of the coil stack i.e.. overheating of the top coil. is believed to be related, in part, to the inherent tendency of heated furnace atmosphere gases to rise to the top of the furnace. the initially relatively cold and massive furnace base. and nonuniformities in the circulation of the furnace atmo sphere.
  • the major cause of localized overheating is believed to be related to the fact that the top coil has a relatively greater surface area exposed to radiant and convected heat than other portions of the coil stack. This condition is especially noticeable when annealing covers are employed to cover the coil stack because the cover serves as a source of radiant energy.
  • Coil stack temperature uniformity is a desirable, and oftentimes essential, consideration in the successful attainment of uniform mechanical properties during the heattreatment of metals. This is especially true when the heat-treating temperature of a metal must be maintained within a narrow range due to metallurgical considcrations. Cold rolled high strength low alloy steels are typical of such steels. Uniformity is also generally desirable in the annealing of both plain carbon and alloy steels in which unduly broad temperature variations may lead to the formation of undesirable phase transformations. precipitated secondary phases, undesirable surface carbides. variations in hardness and other mechanical properties, etc. Our inventive heat shield is effective in reducing or eliminating problems of the above nature through the expedient of improved control of thermal uniformity.
  • cover plates are also known in the art of heat-treating metallic coils. Typical cover plates are illustrated in U.S. Pat. Nos. 2.495.561, 3,211,590. 3,302,939. and 2.678.815. Such plates are of various designs and are adapted for the particular purposes of the respective patents.
  • the heat shield assembly has utility in a wide variety of commercial batch heat treating systems. For example, it is immaterial as to whether or not the system employs an annealing cover, forced atmosphere circulation, or whether the furnace is direct fired or is radiant tube heated. The nature of the furnace atmosphere is likewise immaterial to the practice of the invention.
  • the heat shield of the invention is suitable for use in the heat-treatment of any product in which it is desirable to prevent localized overheating ofa portion of the charge. Furnaces in which either single or multiple stacks of coils are heat-treated may be used in combination with the heat shield.
  • Our invention comprises a heat shield which will reduce the extent of localized overheating of the charge and which will also be resistant to warpage due to thermal expansion and contraction during use in the heattreating process. Despite substantial thermal gradients across the shield thickness, shield warpage is minimized due to its particular structural configuration. Warpage prevention is not only an important factor relating to insulating efficiency during a use of the heat shield, but is also of commercial significance when it is considered that the heat shield is intended to be reused numerous times.
  • lt is a further objective to provide a heat shield assembly which is resistant to thermal warpage and is dimensionally stable during its use in a heat-treatment process and is further suitable for prolonged reuse in subsequent heat-treating processes.
  • FIG. 1 is a top view of a quadrant of the heat shield assembly.
  • FIG. 2 is a side sectional view of the heat shield taken along Section AA of FIG. 1. This figure also illustrates that the heat shield is positioned over the top of a coil during its use in a heat treating process.
  • FIG. 3 illustrates an unshielded stack of coils in which coil temperatures were measured at the various indicated positions.
  • FIG. 4 illustrates a shielded stack of coils in which coil temperatures and heat shield temperatures were measured at the various indicated positions.
  • FIG. 5 is a graphical depiction of the thermal history of various portions of a stack of coils subjected to heattreatment without use of a heat shield.
  • HO. 6 is a graphical depiction of the thermal history of various portions of a stack of coils subjected to heattreatment with use of a heat shield.
  • the shield assembly comprises two attached substantially circular plates having central openings and containing multiple radial slots. Thermal warpage is minimized through use of the radial slots because the slotted portions of the respective plates can expand and contract independently of unslotted plate portions.
  • the plates are fastened to each other in a loose or non-rigid fashion at locations proximate to their outer peripheries and also to their central openings. This type of connection enables the plates to move independently of each other and, hence. prevents potential warpage due to the transmission of temperature differential induced bending moments between the plates.
  • An insulating material is interposed between the respective plates in order to provide the requisite insulating capability of the heat shield.
  • spacers are provided between the respective plates in order to maintain dimen sional stability of the assembly and to prevent the crushing of the insulating material.
  • FIGS. 1 and 2 A preferred embodiment of the heat shield assembly is depicted in FIGS. 1 and 2.
  • FIG. 1 is a top view of a quadrant of the heat shield while FIG. 2 is a side view of the heat shield taken along Section A-A of FIG. I.
  • the heat shield assembly comprises upper plate 1 and lower plate 2. each plate having a central opening. Insulating material 3 is interposed between plates 1 and 2 so as to provide for the requisite heat insulating properties.
  • a typical insulating material suitable for practice of the invention is FlBER- FAX ceramic fiber manufactured by The Carborundum Company. Niagara Falls. NY. This insulating material comprises a lightweight flexible batting of interlocked ceramic fibers. Of course, numerous other com sharpally available insulating materials in loose form as well as in sheet or blanket form are also suitable.
  • U-shaped channel 4 The respective plates are fastened or held together at a location proximate to the respective central openings by U-shaped channel 4.
  • the slightly oversized channel holds plates 1 and 2 together through slidable contact of its legs and the plate surfaces. Such arrangement permits plates 1 and 2 to thermally expand and contract independently upon heating and cooling. This feature precludes significant warpage of the assembly during use.
  • U-shaped channel 4 also serves the additional function of limiting the passage of atmospheric gases between plates 1 and 2, thus, improving the insulating efficiency of the heat shield. Channel 4 also serves to prevent the loss of insulating material 3 from the assembly. It is understood that other suitable fastening means could be employed to hold plates 1 and 2 together at the central opening. For example. a loose bolting arrangement or the like would be also suitable.
  • Bolting arrangement 5 is used to attach plates 1 and 2 at an outer radial position. As is apparent from the drawing. the bolting arrangement provides a loose means of attachment so as to permit plates 1 and 2 to expand and contract independently from each other upon heating and cooling. This arrangement also precludes significant warpage of the assembly. Ring member 6 is placed between plates 1 and 2 near the outside perphery of the assembly for the purpose of preventing the loss of insulating material. There is no need to affix ring 6 to either plate 1 or 2 as the ring will remain in place inherently due to its structural configuration. Fastening means similar to that of U-channel 4 may be substituted for bolting arrangement 5 and ring member 6. However. such substitution involves significantly more weight. Thus, the illustrated bolting arrangement is a preferred fastening means.
  • Centering means 7 is attached to the lower leg of U- shaped channel 4 for the purpose of facilitiating the placement of the heat-shield on top of coil 9 prior to the start of the heat-treatment. Centering means 7 fits into the inside diameter of coil 9 this assuring uniform positioning of the heat shield. When it is considered that commercial practice of the invention on a typical industrial scale involves the positioning of a rather heavy object on the top of a rather high stack of coils with a crane or similar lifting device, it will be readily appreciated that such centering means is of substantial assistance. This design also facilitiates the stacking of shield when they are not in use. Centering means 7 may consist of a series of radial spokes or a solid shell-like member in the form of a truncated cone.
  • solid shell-like centering means is preferred when the invention is practiced in a furnace assembly in which the annealing atmosphere is controllably circulated with the use of a centrally located base fan because a solid shell-like member will serve to prevent atmosphere gas from passing over the top coil instead of passing through convector plates which separate the coils in the bottom portion of the stack.
  • the open bottom of the solid shell-like truncated cone fixes the effective central opening of the heat shield through which circulating atmosphere gas passes. in the event that it is desired to reduce or even to close the area of this already existing central opening it is possible to insert a ring or disc into the truncated cone to effect such area adjustment.
  • FIG. 1 represents a top view of the heat shield. This view illustrates two additional features of the invention.
  • Radial slots 10 serve to prevent warpage of the two plates.
  • the multiple radial slots permit the outer peripheries of the respective plates to expand and contract independently of the central portion of the plates. thus. minimizing potential plate warpage.
  • Spacing members 11 are placed between plates 1 and 2 to pre vent curshing of insulating material 3 and to maintain dimensional stability of the assembly. Only one plate should be attached to spacing members 11 so as to avoid potential warpage of the assembly. By such method of attachment, the spacer is free to move in sliding contact with the unattached plate during thermal expansion and contraction. Tack welding has been found to be a suitable attachment technique.
  • Hairpin shaped solid bars are a perferred type of spacing means due to assembly fabrication considerations. However, discrete spaced vertical bars or pipes attached to one plate only would also constitute equivalent spacing means.
  • a three-high stack of low carbon steel coils was annealed in a direct fired multiple stack portable type annealing furnace.
  • the same th ee coils were heated according to the same annealing cycle with and without use of the heat shield of the invention.
  • FIBERFAX ceramic fiber in blanket form was used in the heat shield as the insulating material.
  • the batch annealing furnace contained an HNX atmosphere which was circulated downwardly through the respective coil inside diameters by a base fan.
  • HNX atmospheres typically comprise about 7% H 93% N less than 01% CO, and less than 0.l% CO and have a dew point range of about -4()F to 60F.
  • the intent of the annealing cycle was to obtain a temperature range of from l,280F.
  • l,330F in the annealing stack.
  • This treatment is conventionally utilized to anneal cold rolled low carbon steel coils.
  • An upper limit of l,3 30F. is selected so as to avoid the formation of austenite while the lower limit of l,280F is needed to assure that desired machanical properties are obtained.
  • FIG. 3 illustrates the coil locations in which temperature measurements were taken for the unshielded coil stack. Coil temperature measurements were also taken at the same locations for the heat shielded coil stack. These locations are illustrated in FIG. 4. Also. denoted in FIG. 4 are locations A and B which correspond to the temperatures measured throughout the cycle at the top and bottom of the heat shieldv All temperature measurements were taken with mineral insulated sheath thermocouples which were wrapped in the coil at the indicated locations.
  • the coil sizes, heat-treating furnace, and furnace conditions were selected to be representative of actual industrial conditions. Starting from the lowermost coil. the coil weights were 26.36 tons. 12.29 tons. and l4. tons, respectively; the coil heights were 65 in.. 30 in., and 37 in., respectively; and the outside coil diameters were 64.8 in.. 65.3 in., and 63.2 in, respectively.
  • FIG. 5 represents a plot of temperature measurements throughout the annealing cycle taken at the locations shown in FIG. 3. This data is typical of the thermal history of batch annealed coils which have not been protected by a heat shield. As can be seen from the plot. a substantial portion of the top coil was overheated. i.e., heated above the maximum aim temperature of 1.330F. Also of interest is the relatively short time of exposure any coil to the aim range of l,280F. to 1.330F.
  • Curves A and B of FIG. 6 indicate the substantial thermal gradient which is created across the heat shield thickness during the annealing cycle.
  • the thermal graident also leads to certain advantages of substantial operating significance.
  • Use of the heat shield permits the furnace operator to utilize higher furnace temperatures during the heat-up stage of the cycle. Higher initial furnace temperatures then lead to shorter heat-up times, thus, resulting in shorter overall cycle times.
  • lower furnace temperatures would be required upon heat-up due to the tendency of the topmost coil to overheat. It is also apparent that shorter soaking times may be utilized with heat shielded coils due to increased temperature uniformity and the consequent ability to more readily maintain the entire charge within a desired temperature range.
  • a heat shield assembly having a central opening for the prevention of localized overheating during batch heat-treatment of coils comprising:
  • a second substantially circular plate having a central opening and containing multiple radial slots whereby thermal warpage of said second plate would be minimized upon heating and cooling during said heat-treatment;
  • a first fastening means in contact with said first and second plates at a position proximate to said respective central openings of said first and second plates for loosely fastening said first and second plates so as to permit said first and second plates to expand and contract independently upon heating and cooling;
  • a second fastening means in contact with said first and second plates at an outer radial position of said first and second plates for loosely fastening said first and second plates so as to permit said first and second plates to expand and contract independently upon heating and cooling;
  • spacing means located between and in contact with said first and second plates so as to prevent the crushing of said insulating material and to maintain dimensional stability of said heat shield assembly.
  • a heat shield assembly having a central opening for the prevention of localized overheating during batch heat-treatment of coils as recited in claim I, wherein:
  • said first fastening means comprise a U-shaped channel member having legs in slidable contact with said first and second plates so as to permit said first and second plates to expand and contract independently upon heating and cooling.
  • a heat shield assembly having a control opening for the prevention of localized overheating during batch heat-treatment of coils as recited in claim 2, wherein:
  • said second fastening means comprise both members attached loosely to said first and second plates so as to permit said first and second plates to expand and contract independently upon heating and cooling.
  • a heat shield assembly having a central opening for the prevention of localized overheating during batch heat-treatment of coils as recited in claim I. wherein:
  • said spacing means comprise hairpin shaped bars.
  • a heat shield assembly having a central opening for the prevention of localized overheating during batch heat-treatment of coils as recited in claim 1, which further includes:
  • thermoelectric positioning means connected to said heat shield assembly proximate to said central opening of said first and second plates for assisting in the placement of said heat shield assembly on a top surface of a top coil.
  • a heat shield assembly having a central opening for the prevention of localized overheating during batch heat-treatment of coils as recited in claim 5, wherein:
  • said positioning means comprise a solid shell in the form of a truncated cone.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Heat Treatments In General, Especially Conveying And Cooling (AREA)
  • General Induction Heating (AREA)
US461814A 1974-04-18 1974-04-18 Non-warping heat shield Expired - Lifetime US3879167A (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
US461814A US3879167A (en) 1974-04-18 1974-04-18 Non-warping heat shield
AU79549/75A AU482155B2 (en) 1974-04-18 1975-03-26 Non-warping heat shield for batch treatment of metal coils
NL7503677A NL7503677A (nl) 1974-04-18 1975-03-27 Niet-werkend hitteschild.
FR7510211A FR2268081B1 (cs) 1974-04-18 1975-04-02
DE19752515264 DE2515264A1 (de) 1974-04-18 1975-04-08 Hitzeschild
IT22100/75A IT1034923B (it) 1974-04-18 1975-04-08 Schermo termico indeformabile
CA224,243A CA1035946A (en) 1974-04-18 1975-04-09 Non-warping heat shield for batch heat treatment of metal coils
GB15940/75A GB1496394A (en) 1974-04-18 1975-04-17 Non-warping heat shield
JP50046930A JPS50145308A (cs) 1974-04-18 1975-04-17

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US461814A US3879167A (en) 1974-04-18 1974-04-18 Non-warping heat shield

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US3879167A true US3879167A (en) 1975-04-22

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US461814A Expired - Lifetime US3879167A (en) 1974-04-18 1974-04-18 Non-warping heat shield

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US (1) US3879167A (cs)
JP (1) JPS50145308A (cs)
CA (1) CA1035946A (cs)
DE (1) DE2515264A1 (cs)
FR (1) FR2268081B1 (cs)
GB (1) GB1496394A (cs)
IT (1) IT1034923B (cs)
NL (1) NL7503677A (cs)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3975145A (en) * 1974-04-29 1976-08-17 Lee Wilson Engineering Company, Inc. Open coil heat shielding
WO1981000610A1 (en) * 1979-08-14 1981-03-05 Mareck Bv Combustion chamber
US4423857A (en) 1982-07-06 1984-01-03 Stelco Inc. Spacer for batch coil annealing
US4498884A (en) * 1981-03-16 1985-02-12 U.S. Philips Corporation Method of manufacturing a display tube
US4569508A (en) * 1982-05-26 1986-02-11 Hoogovens Groep B.V. Metallurgical vessel having an opening and a flange around the opening
US4813654A (en) * 1987-11-09 1989-03-21 Lee Wilson Engineering Company, Inc. Annealing furnace base construction
US6495094B1 (en) * 1999-11-09 2002-12-17 Mitsubishi Heavy Industries, Ltd. Apparatus and method for suppressing growth of oxide film on coil
WO2005001361A1 (en) * 2003-06-27 2005-01-06 Sandvik Intellectual Property Ab Improved heat conductor support disc.
WO2006031166A1 (en) * 2004-09-16 2006-03-23 Sandvik Intellectual Property Ab Furnace insulation

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5906816B2 (ja) * 2012-03-01 2016-04-20 Ｊｆｅスチール株式会社 金属帯コイルの焼鈍方法および焼鈍炉

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2489012A (en) * 1946-12-28 1949-11-22 Carnegie Illinois Steel Corp Gas circulating separator
US3056594A (en) * 1959-06-10 1962-10-02 Lee Wilson Coil stabilizer
US3386721A (en) * 1965-12-20 1968-06-04 Hazen Engineering Company Convector plates for coil annealing apparatus
US3661371A (en) * 1969-05-13 1972-05-09 Skelton Thomas Ltd Convector plates

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5113908Y2 (cs) * 1971-02-20 1976-04-13

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2489012A (en) * 1946-12-28 1949-11-22 Carnegie Illinois Steel Corp Gas circulating separator
US3056594A (en) * 1959-06-10 1962-10-02 Lee Wilson Coil stabilizer
US3386721A (en) * 1965-12-20 1968-06-04 Hazen Engineering Company Convector plates for coil annealing apparatus
US3661371A (en) * 1969-05-13 1972-05-09 Skelton Thomas Ltd Convector plates

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3975145A (en) * 1974-04-29 1976-08-17 Lee Wilson Engineering Company, Inc. Open coil heat shielding
WO1981000610A1 (en) * 1979-08-14 1981-03-05 Mareck Bv Combustion chamber
US4498884A (en) * 1981-03-16 1985-02-12 U.S. Philips Corporation Method of manufacturing a display tube
US4569508A (en) * 1982-05-26 1986-02-11 Hoogovens Groep B.V. Metallurgical vessel having an opening and a flange around the opening
US4423857A (en) 1982-07-06 1984-01-03 Stelco Inc. Spacer for batch coil annealing
US4813654A (en) * 1987-11-09 1989-03-21 Lee Wilson Engineering Company, Inc. Annealing furnace base construction
US6495094B1 (en) * 1999-11-09 2002-12-17 Mitsubishi Heavy Industries, Ltd. Apparatus and method for suppressing growth of oxide film on coil
WO2005001361A1 (en) * 2003-06-27 2005-01-06 Sandvik Intellectual Property Ab Improved heat conductor support disc.
US7692122B2 (en) 2003-06-27 2010-04-06 Sandvik Intellectual Property Ab Heat conductor support disc
CN1836144B (zh) * 2003-06-27 2010-11-03 桑德维克知识产权股份公司 改进的导热体支撑盘
WO2006031166A1 (en) * 2004-09-16 2006-03-23 Sandvik Intellectual Property Ab Furnace insulation
US20080196641A1 (en) * 2004-09-16 2008-08-21 Sandvik Intellectual Property Ab Furnace Insulation
US8085829B2 (en) 2004-09-16 2011-12-27 Sandvik Intellectual Property Ab Furnace insulation

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Publication number Publication date
GB1496394A (en) 1977-12-30
FR2268081B1 (cs) 1978-10-06
IT1034923B (it) 1979-10-10
FR2268081A1 (cs) 1975-11-14
NL7503677A (nl) 1975-10-21
JPS50145308A (cs) 1975-11-21
AU7954975A (en) 1976-09-30
DE2515264A1 (de) 1975-11-20
CA1035946A (en) 1978-08-08

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AS Assignment

Owner name: JONES & LAUGHLIN STEEL, INCORPORATED

Free format text: MERGER;ASSIGNORS:JONES & LAUGHLIN STEEL CORPORATION, A CORP. OF PA.;YOUNGTOWN SHEET & TUBE COMPANY,A CORP. OF OH. (MERGED INTO);NEW J&L STEEL CORPRATION, A CORP. OF DE., (CHANGED TO);REEL/FRAME:004510/0801

Effective date: 19851018

AS Assignment

Owner name: LTV STEEL COMPANY, INC.,

Free format text: MERGER AND CHANGE OF NAME EFFECTIVE DECEMBER 19, 1984, (NEW JERSEY);ASSIGNORS:JONES & LAUGHLIN STEEL, INCORPORATED, A DE. CORP. (INTO);REPUBLIC STEEL CORPORATION, A NJ CORP. (CHANGEDTO);REEL/FRAME:004736/0443

Effective date: 19850612