EP0056976A1 - Refroidissement par liquide d'un arrangement de coulée ayant un joint d'étanchéité à fluide - Google Patents

Refroidissement par liquide d'un arrangement de coulée ayant un joint d'étanchéité à fluide Download PDF

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Publication number
EP0056976A1
EP0056976A1 EP82100365A EP82100365A EP0056976A1 EP 0056976 A1 EP0056976 A1 EP 0056976A1 EP 82100365 A EP82100365 A EP 82100365A EP 82100365 A EP82100365 A EP 82100365A EP 0056976 A1 EP0056976 A1 EP 0056976A1
Authority
EP
European Patent Office
Prior art keywords
coolerbody
ring
strand
die
cooling fluid
Prior art date
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.)
Granted
Application number
EP82100365A
Other languages
German (de)
English (en)
Other versions
EP0056976B1 (fr
Inventor
Calvin Rushforth
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.)
Kennecott Mining Corp
Original Assignee
Kennecott Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Kennecott Corp filed Critical Kennecott Corp
Priority to AT82100365T priority Critical patent/ATE12900T1/de
Publication of EP0056976A1 publication Critical patent/EP0056976A1/fr
Application granted granted Critical
Publication of EP0056976B1 publication Critical patent/EP0056976B1/fr
Expired legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/14—Plants for continuous casting
    • B22D11/145—Plants for continuous casting for upward casting

Definitions

  • the present invention relates generally to a fluid cooled casting apparatus for the continuous casting of metallic strand and, more particularly, to such an apparatus having an improved cooling fluid seal which facilitates repair and maintenance.
  • the present invention resides in an improvement to an apparatus for the continuous casting of a metallic strand from a metallic melt.
  • the conventional apparatus has a die of refractory material in fluid communication with the melt through which die the metallic strand is drawn.
  • a thermally conductive coolerbody surrounds at least a portion of the die to extract heat therefrom.
  • the conventional casting apparatus also includes a conduit for passing a cooling fluid through the coolerbody.
  • the improvement of the present invention comprises O-ring seals mounted to the coolerbody for containing the cooling fluid within the conduit, and a thermal barrier within the coolerbody adjacent the O-ring seals for maintaining the temperature of the O-ring at a level insufficient to damage the O-rings.
  • two O-ring seals are used: one surrounding the lower portion of the coolerbody and the other 'surrounding the upper portion.
  • the thermal barrier associated with the lower O-ring consists of an extension of the cooling fluid-bearing conduit to a point at which it intersects the portion of the coolerbody between the O-ring and the die, so as to counteract the transmission of heat from the die to the O-ring.
  • the thermal barrier associated with the upper O-ring also includes such an extension of the cooling fluid conduit to the region between the O-ring and the enclosed metallic strand.
  • this upper barrier also utilizes a hollow cylindrical insert made of a material with a relatively poor thermal conductivity, which fits into a recess within the coolerbody and produces two heat-retarding air gaps, one between the outer surface of the insert and the coolerbody, and a second between the inner surface of the insert and the metallic strand.
  • the thermal barriers limit the temperatures experienced by the O-rings so that they are not subjected to the temperatures which would melt the O-rings or otherwise deteriorate the seal.
  • This embodiment also features an annular ring which surrounds the lower portion of the coolerbody at the location of the lower O-ring and is bolted at several locations to the coolerbody.
  • the inner surface of the annular ring compresses the lower O-ring and effects a seal.
  • a threaded bayonet-type coupling receives the threaded upper portion of the coolerbody and is arranged such that a portion of the coupling compresses the upper O-ring to effect a seal.
  • the cylindrical insert is press-fit to the coupling and extends into the interior of the coolerbody. To gain access to the interior of the coolerbody for maintenance, it is ' a simple matter to remove the mounting bolts holding the annular ring to the lower portion of the coolerbody, and then to unscrew the upper portion of the coolerbody from the coupling.
  • the structure as described herein is generally acceptable for production of a metallic strand having a diameter up to 2 1/2 inches.
  • certain operating parameters may vary such as, for example, the rate of flow of cooling fluid through the coolerbody, the length and total outer surface area of the coolerbody, and the thickness of the refractory material die.
  • a hollow, generally tubular die 11 is oriented in a vertical direction with its lower end lla protruding into a melt 12 of the particular metal being cast.
  • the melt is drawn upwardly through the die in any conventionally known manner, and is cooled into a metallic strand 14.
  • the upper portion of the die 11 is tightly contained within a cylindrical cavity 13 formed in the interior of a coolerbody 15.
  • the die is made of a refractory material, such as graphite, which can withstand the thermal shock generated by the casting process, while the coolerbody is made of a metal having exceptionally good thermal conductivity characteristics, such as copper, or a copper alloy.
  • the die 11 fits snuggly within the cavity 13 to provide maximum contact between the outer surface of the die-and an inner surface 15a of the coolerbody, across which interface extraction of the heat of solidification from the strand 14, through the die 11, is accomplished.
  • Insulating inserts or bushings 17, 17a surround the die 11 at the location where the die 11 enters into the coolerbody 15.
  • These bushings 17 are formed of a refractory material having a relatively low coefficient of thermal expansion such as, for example, cast silica glass (SiO 2 ). They prevent expansion of the die at this location and maintain a uniform cross-section of the cast strand.
  • the die would thermally expand, due to the extreme heat of the melt in which it is deposited, and would produce a strand having a diameter larger than the inner diameter of the rest of the die. Were this the case, this larger diameter strand could wedge within the narrower upper portion of the die causing blockage of the die and interruption of the casting process.
  • the coolerbody 15 In order to dissipate the heat extracted by the coolerbody 15 from the die 11, it is necessary to direct a flow of cooling water or other acceptable cooling fluid across an outer surface 15b of the coolerbody 15.
  • the outer surface 15b of ; the coolerbody consists of a series of thirty-two radially extending fins 19 of equal height, which are distributed at equal spacings around the outer periphery- of the coolerbody. It is intended that alternate heat dissipating surface configurations be used as well such as, for example, the configuration disclosed in the coolerbody of the above-mentioned U.S. Patent No. 4,211,270.
  • the coolerbody has two concentrically arranged groups of parallel cylindrical holes which extend down into the coolerbody.
  • the fin configuration of FIG. 1 is particularly suitable for the casting of larger diameter strands larger than 3/4 inch for which a significantly longer coolerbody is required to properly cool the larger mass strand.
  • the longer the coolerbody the more difficulty it becomes to drill long, straight, parallel holes through the coolerbody because of the tendency of the longer drill bit to vibrate and wander or deviate from a straight line.
  • the external fin configuration is preferable because it can more easily and quickly be machined on a milling apparatus and, therefore, is less costly to fabricate.
  • Two concentric annular passageways or conduits 21, 23, for transporting the cooling fluid which passes over the finned outer surface 15b of the coolerbody, are formed by a concentric arrangement of three coolant sleeves, an inner sleeve 25 (see . Fig. 1), a middle sleeve 27, and an outer sleeve 29, which fit one within another.'
  • Each of these coolant sleeves is attached at its upper end to a manifold (not shown) which constitutes the source of the cooling fluid to be circulated through the passageways 21, 23.
  • a fluid inlet (not shown) communicates with the inner passageway 21 while a fluid outlet (not shown) communicates with the outer passageway, so that the cooling fluid is pumped downwardly into the inner passageway 21, across the fins 19, thereby extracting heat therefrom, through a transverse passage 31, and upwardly through the outer passageway 23 to be discharged.
  • the rate of flow of the cooling fluid varies, depending on such factors as the size of the strand being cast, the wall thickness of the die, or the length of the coolerbody. However, the design objective sought is that the cooling fluid temperature increase from inlet to outlet shall be in the range of 10° to 15°F. The rate of flow is adjusted to achieve this objective.
  • the outer coolant sleeve 29 extends downwardly from the cooling fluid manifold and encompasses almost the entire coolerbody 15.
  • a positioning ring 33 secured by bolts 35 to a shoulder 37 machined in the coolerbody 15, anchors the bottom end of the outer coolant sleeve 29.
  • the positioning ring 33 has an upwardly extending central lip portion 39 which creates two recesses 41, 42.
  • the outer recess 41 accommodates the bottom end of the outer coolant sleeve 29; and, the inner recess 42 receives the bottom portion of the middle coolant sleeve 27.
  • the outer coolant sleeve 29 is welded or joined in any other suitable fashion to the positioning ring 33 to increase the structural integrity and stability of the assembly.
  • the middle coolant sleeve 27 is merely press-fit into the inner recess 42.
  • a small clearance space 43 is provided between the outer edges 19a (see FIG. 2) of the fins 19 to.maximize the surface area contacted by the cooling fluid.
  • the cooling fluid contacts not only the radially extending walls of the fins, but also the outer circumferential edge surfaces 19a as well.
  • the bottom end of the inner coolant sleeve 25 is welded at 44 to a coupling ring 45, which mechanically engages the upper portion of the coolerbody in a manner described hereinafter in greater detail.
  • the weld 44 provides a fluid-tight seal to prevent the passage of cooling fluid into the interior of the sleeve 25.
  • the inner coolant sleeve 25 form part of the inner passageway 21, but its bore 46 serves to guide the movement of the cast strand after emergence of the strand from the snug- fitting confines of the die 11. Within this bore 46 heat continues to emanate from the strand, is transmitted by convection to the inner coolant sleeve 25, and is dissipated by the cooling fluid passing over the inner coolant sleeve outer surface.
  • a lower and an upper O-ring seal, 48, 49 respectively, made of a resilient compressible material, are provided.
  • the lower O-ring 48 fits within a recess 51 provided in a projection 53 integrally formed within the-lower portion of the coolerbody 15. It can be seen that this projection 53 also provides a shoulder which determines the lateral placement of the positioning ring 33.
  • the lower O-ring 48 is compressed into a seal between an outwardly facing surface 51a of the recess 51 and an inwardly facing and oppositely directed surface 33a of the positioning ring 33.
  • the seal will prevent passage of the cooling fluid below the level of the O-ring 48.
  • the upper O-ring 49 similarly is seated within a circular recess 55 formed within an outward lobe 57 extending from an upwardly directed neck portion 59 of the coolerbody 15.
  • the neck portion is threaded directly above this lobe at 60.
  • the coupling ring 45 has a receptacle portion 63 with a mating thread 65 which receives the threaded neck portion 60 of the coolerbody.
  • the neck portion 59 is threadably engaged within the coupling ring 45 and is advanced to the fully seated position, as determined by the engagement of a top edge 67 of the neck with an inner surface 69 of the coupling ring. In this position, the O-ring is compressed between an outwardly facing surface 55a of the circular recess 55 and an inwardly ; facing surface of a vertical flange 71 integrally formed with the coupling ring 45.
  • a particularly suitable material used for the sealing 0-rings 48, 49 is Viton (a trade name of E.I. duPont de Nemours and Company, Inc. for synthetic rubber). In order for this material to maintain proper resiliency and other sealing qualities, the temperature to which it is exposed must not exceed 350°F. Unless compensated for, the extremely good thermal conductivity characteristics of the coolerbody may cause the temperatures at the O-rings to exceed the 350°F danger point during casting.
  • a thermal barrier, in the form of a circular channel 73 cut into the coolerbody 15, is provided to protect the lower O-ring 48.
  • the channel 73 which forms an extension of the inner passageway 21, is intermediate the O-ring 48 and the die 11 from which the heat of solidification is being extracted.
  • the channel 73 interrupts the direct metallic path between the die and the O-ring 48 but, by extending so close to the recess 51, it also provides for_localized cooling of the coolerbody immediately adjacent the O-ring 48.
  • the channel has a dual effect on the temperature experienced by the O-ring 48.
  • the cooling water after passing through the fins 19, circulates within the channel 73 before continuing through the transverse passage 31 into the outer annular passage 23, and then finally out through the outlet (not shown).
  • the outer diameter of the insert 77 is smaller than the inner diameter of the recess 78, so that an air gap 79 separates the outer surface of the insert 77 from the coolerbody 15.
  • the heat shield insert 77 has an inner diameter which is larger than the diameter of the strand so that there is provided a second air gap 81 separating the strand from the insert.
  • the air gaps form discontinuities in the highly thermally conductive path provided by the coolerbody between the casting and the O-ring 49, and thus retards the heat flow.
  • an even more significant amount of resistance to the heat flow is provided by the presence of stagnant films of air which form on each of the surfaces defining the air gaps. Absent the shield insert 77, there would be only one such air gap, namely between the outer surface of the strand and the inner surface of the coolerbody, and therefore only two such air films on the respective surfaces.
  • two additional intervening surface films are created, namely on the inner and outer surfaces of the shield insert 77. Doubling the number of surface films effectively cuts in half the heat flux passing between the strand and the coolerbody.
  • a typical material, out of which the insert may be fabricated, is #304 stainless steel, having a heat conductivity of about 0.036 cal-cm/cm 2 /°C/sec, considerably lower than the heat conductivity of a copper coolerbody, which is about 0.94 cal-cm/cm 2 /°C/sec.
  • the upper end of the heat shield insert 77 is press-fit within a mating recess in the coupling ring 45, so that when the coolerbody is unscrewed from the coupling ring 45, the insert 77 remains within the coupling ring. Therefore, the total thermal protection provided to the upper O-ring 49 is the combination of the inner air gap 81, the low-conductivity heat shield insert 77, the outer air gap 79, the four stagnant surface air films and the cooling fluid passageway extension 75.
  • the upper and lower O-ring seals are cheaper and easier to fabricate than the previously used brazed seals, but they also facilitate disassembly of the casting apparatus for maintenance.
  • it is a simple matter after removing the outer ceramic protective cap 47 (see FIG. 1), to unbolt the series of bolts 35 extending around the periphery of the lower portion of the coolerbody, to detach the coolerbody from the positioning ring 33, to unscrew the coolerbody from the coupling ring 45 and remove it as an integral unit from the interior of the coolant sleeve 27.
  • a space 91 shown between the bottom of the heat shield insert 77 and a lower lip 93 of the recess 78 is of such a magnitude that the thermal expansion experienced by the shield insert 77 during operation of the casting apparatus will close up this gap and provide a barrier against contaminating vapors such as, for example,.the zinc vapors which are by-products of the brass-casting process. Containment of the gaseous vapors minimizes the possibility of their condensation within the casting apparatus and facilitates their evacuation therefrom.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Continuous Casting (AREA)
  • Molds, Cores, And Manufacturing Methods Thereof (AREA)
  • Moulding By Coating Moulds (AREA)
  • Thermotherapy And Cooling Therapy Devices (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)
EP82100365A 1981-01-26 1982-01-20 Refroidissement par liquide d'un arrangement de coulée ayant un joint d'étanchéité à fluide Expired EP0056976B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT82100365T ATE12900T1 (de) 1981-01-26 1982-01-20 Fluessigkeitsgekuehlte giesseinrichtung mit verbesserter fluessigkeitsdichtung.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US22854981A 1981-01-26 1981-01-26
US228549 1981-01-26

Publications (2)

Publication Number Publication Date
EP0056976A1 true EP0056976A1 (fr) 1982-08-04
EP0056976B1 EP0056976B1 (fr) 1985-04-24

Family

ID=22857637

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82100365A Expired EP0056976B1 (fr) 1981-01-26 1982-01-20 Refroidissement par liquide d'un arrangement de coulée ayant un joint d'étanchéité à fluide

Country Status (10)

Country Link
EP (1) EP0056976B1 (fr)
JP (1) JPS57175060A (fr)
AT (1) ATE12900T1 (fr)
AU (1) AU542870B2 (fr)
CA (1) CA1183322A (fr)
DE (1) DE3263197D1 (fr)
DK (1) DK22882A (fr)
FI (1) FI68180C (fr)
NO (1) NO820187L (fr)
ZA (1) ZA82334B (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE1000430A5 (fr) * 1985-10-22 1988-12-06 Vertic Oy Combinaison d'ajutages de coulee pour couler des produits du genre de barres et tubulaires verticalement vers le haut.

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6319947U (fr) * 1986-07-22 1988-02-09
US5404932A (en) * 1990-10-17 1995-04-11 Outokumpu Castform Oy Apparatus and method for intensifying cooling in the casting of metal objects

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2124424A1 (de) * 1970-05-19 1971-12-02 Outokumpu Oy, Outokumpu (Finnland) Verfahren und Vorrichtung zum kontinuierlichen aufwärtsgerichteten Gießen von Rohren, Stangen, Platten u. dgl
DE2060451B2 (de) * 1969-12-15 1974-01-31 Outokumpu Oy, Outokumpu (Finnland) Vorrichtung zum aufwärtsgerichteten Stranggießen von Profilstücken
BE815738Q (fr) * 1970-12-14 1974-09-16 Procede en continu pour la coulee ascendante de barres
US4211270A (en) * 1978-07-28 1980-07-08 Kennecott Copper Corporation Method for continuous casting of metallic strands at exceptionally high speeds

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2060451B2 (de) * 1969-12-15 1974-01-31 Outokumpu Oy, Outokumpu (Finnland) Vorrichtung zum aufwärtsgerichteten Stranggießen von Profilstücken
DE2124424A1 (de) * 1970-05-19 1971-12-02 Outokumpu Oy, Outokumpu (Finnland) Verfahren und Vorrichtung zum kontinuierlichen aufwärtsgerichteten Gießen von Rohren, Stangen, Platten u. dgl
US3746077A (en) * 1970-05-19 1973-07-17 Outokumpu Oy Apparatus for upward casting
BE815738Q (fr) * 1970-12-14 1974-09-16 Procede en continu pour la coulee ascendante de barres
US4211270A (en) * 1978-07-28 1980-07-08 Kennecott Copper Corporation Method for continuous casting of metallic strands at exceptionally high speeds

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE1000430A5 (fr) * 1985-10-22 1988-12-06 Vertic Oy Combinaison d'ajutages de coulee pour couler des produits du genre de barres et tubulaires verticalement vers le haut.

Also Published As

Publication number Publication date
JPS57175060A (en) 1982-10-27
ATE12900T1 (de) 1985-05-15
FI820225L (fi) 1982-07-27
JPS6121740B2 (fr) 1986-05-28
FI68180B (fi) 1985-04-30
DE3263197D1 (en) 1985-05-30
EP0056976B1 (fr) 1985-04-24
AU7959282A (en) 1982-08-05
ZA82334B (en) 1982-11-24
CA1183322A (fr) 1985-03-05
NO820187L (no) 1982-07-27
FI68180C (fi) 1985-08-12
AU542870B2 (en) 1985-03-21
DK22882A (da) 1982-07-27

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