Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
~læ~7~
~IETIIOD AND ~PPA~'l`US FOR POURING MOLTEN MET~L
IN ~ N~UTR~L ~TMOSPIIER~
Background o r the Irrvention
Technical Field:
This invention relates to a method and apparatus for pour:ing
molten metal into a receiving vessel while excluding atmospheric
air there-from.
~escrLptlon of the PrLor Art:
No prior art tnethods or devices are known whereby a relative~y
simple and inexperlsi.ve closure with or without a pouring sleeve
posi-tioned there-through enable a receiving vessel to be charged
with an inert gas and structurally preven-t the entrance of
atmospheric air thereinto.
Summary of the Inven-tion
~ metlhod and apparatus :Eor pouring molten metal in a
neutral atmosphere are disclosed wherein sl.mpLe and :relat-.Lvely
inexpensLve apparatus placed on a receiving vessel :eo:rms a
closed passageway from a ladle,converter or simiLar source of
molten metal to the receiving vessel and is moved to a position
on the molten metal in the receiving vessel when -the same is
filled to main-tain the closure with respect to.the atmosphere
~LZ297~;
while the mol-ten me-tal is discharged :Erom the receiving vessel.
~ powdered hot top compound may be and preferably is
applied to the surface o-E the mol-ten metal to insure sealing
of the same wi-th respec-t to -the atmosphere and -the movable
closure and closed passageway.
Description of the Drawings
Figure 1 is a fragmentary vertical section through a
portiorl of an ingot mold and illustra-ting -the a-tmosphere
excludlng apparatus in a firs-t position;
Figure 2 is a ver-tical sectional view similar to Figure 1
showing the atmospheric excluding apparatus in a second
position in an ingot mold;
Figure 3 is a top plan view o~ the apparatus seen in
Fi.gure 1~
L5 Figure 4 i.s a perspec-tive view showing the apparatus of
Figures ~L and 3;
Figure 5 is a fragmentary vertical section through a
por-tion of an ingot mold and a modified atmospher;.c excluding
apparatus in a first position thereon;
Figure 6 is a vertical sectional view similar -to Figure 5
' ~
~LZX9'7 3L~i
showing -the atmospheric excluding apparatus in a second
position in the ingot mold; and
~ igure 7 is a perspective view on an enlarged scale showing
a ceramic sleeve which is also seen in ~igures 5 and 6 of -the
drawings.
Description oi the Preeerred Embodimen-t
By re:Eerring to the drawings and Figure 1 in parti.cular
a :Eragmetltary view o:E -the upper por-tion oE a receivin~ vessel
10 which may be an ingo-t mold or a -trumpet -Cunnel O-e a bottom
poured ingot mold or a tundish box -Eor a continuous caster
will be seen -to be substantially filled wi-th molten metal
M which has been introduced in-to -the receiving vessel 10 ~rom
a ladle 11 or o-ther source o:E molten metal. The molten metal
M is introduced in-to the rece:Lving vesse] 10 through an opening
12 located in a closure 13 positioned on the open upper end
o:E the receiving vessel 10. The closure 13 may be a sheet-
like sec-tion o~ insu:Lating fiber board or the like. The opening
12 in the closure 13 is fo:rmed subs-tantially centrally -thereoE
as may be seen by reEerring to Figu:re 4 o-E the drawings.
Mol.ten metal is introduced into the opening 12 of the closure
~L229~7~;
13 from the ladle or other source Oe mo:Lten meta]. by way o:E a
-tubu].c~r nozzle 1~ the lower end po:r-tion Oe which is providecl
with an air lock gaske-t 15 Iormed Oe suitable refractory fiber
materials and the like which is of an overall tapered shape
and thereby capable of registering in the opening 12 in the
closure 13 and -forming an airtigh-t closure.
A pair O e pipes 16 and 17 may be positioned through the
horizontal wal.l of -the closu:re 13 the pipe 16 being connected
by a Ilexible hose 18 wi-th a source of inert gas such as argon
and the pi.pe 17 provides a sui-table lead-in for an alloy wire
19 which can be introduced into -the molten me-tal therethrough
as desired.
Still referring to Figure 1 of the drawings, i-t will be
seen -that the :Lower sur-face of -the closure 13 Oe insula-tillg
fiber board or the like is provided with fold or score
lines 20 defin:Lng a rectangular o:r o-ther shape sLightly smaller
than the inner rectangular or other shape oe the rec.eiving
vessel 1() and by :reeerring to Fi.gure 3 of -the drawings, a
top plan view of -the appara-tus enabling the pouring of molten
metal in a neutral atmosphere will be seen to include broken
~Z~7~S
e representatiorls Oe the eolcl lines or score l:ines 20
together with diagonal extensions thereof at -the -four corners
of -the closure 13 and connecting with -the cu-t ou-t corners
thereof as indicated by the numerals 21.
At such time as the receiving vessel 10 is filled to a
desired level and the inert gas flow con-tinues, an ed~e por-tion
22 oE ~he c].osure 13 and/or -the ladle 11 and nozzle 1~ is lifted
atld a covering coa-ting o~ powdered ho-t -top compound 23, as
knowrl in the art, is applied to the surface of the mol-ten metal.
10. The horizon-tal sheet-like sec-tion o-f -the cl.osure 13 of insulating
:Eiber board or -the like is -then pushed downwardly so as to bend
the longi-tudinal edge portions 22 thereof in angular relation
-there-to and form four angularly disposed edge sections resembl.ing
wipers, each attached to the sheet-l.ike closure 13 o~ insulating
~5 eiber board or the like and each continuously engaging the
inner walls oe the receiving vessel 10 so as to :eorm an
a:irtight closure.
,Vhen -the horizon-tal sectlon of the closure 1~ is pushed
downwardly to contact either the mol-ten metal M or the
powdered hot top compound floating thereon, a secondary closure,
Z,C.3~
no-t shown, may be placed in the opening 1" to ef-fectively seal
the sur-face o:f the molten metal in the vessel 15. At the same
-time the pipes 16 and 17 may be disconnected -from -their respec-
tive sources of gas or metal antl/or removed comp]etely and as
the molten metal ~ in the receiving vessel 10 is fed -therefrom,
as :Eor example into a con-tinuous caster, the entire sealing
apparatus descencls w~th the level o:E the molten metal M and
maintains the atmospheric seal.
In orde:r -to insure the existence of a desirabJe neutral
atmosphere in the receiving vessel. 10 when the first mol-ten
me-tal is poured therein, a smal] quantity of hexamethylene,
also known as cyclohexane, or any o-ther similar readily
vaporizab:l.e liquid having sim-ilar properties is introduced
:Lnto the receiving vessel 10 Wtlell the closure apparatus is first
instal].ed so that the introduction Oe the f-irst molten metal
into the receiving vessel will immediatel.y vapo-rlze the same
and create a suitable gaseous environment that will expel all
of the usual atmosphereic air from -the recei.ving vessel 10
and thus prevent contamination by the reoxiclation of the
molten metal and the undesirable products -thereof.
--8--
.... .... . . . . , ~ :
~ ZZ~37~
?~lodifications in the apparatus ~or pouring molten me-tal
in a neutra~ atmosphlsre will occur to those skilled in the art
and one such modi:eication may comprise -the addition oE exothermic
material as known.in the art into the closure 13 o-E insu]ating
~iber board or the like and/or a-ttaching sections of exothermic
materlal 23A to the lower sur-faces o:f the closure 13 oE insulating
E:Lt)t?r board or the l:lke so that the reac-tion o-E the exothermic
material will add additional heat to the metal in the receiving
vessel and avoid -the usual piping probl.ems -that occur, :Eor
examp~e when mol.ten metal soldiEies in an ingo-t mold or
the like.
Another modi-Eica-tion comprises the use O e a ceramic sleeve
2~L positioned in the opening 12 o:f the closure 13 as seen
in Figures 5,6 and 7 oE the drawings. By re:Eerring thereto
i.t will be seen that this modi:Eication uses an annula:r meta~
band 25 having ver-tically spaced hori~ontally extending annular
Elanges 26 at-tached to the ceramic sl.eeve 24 by suitable
Easteners and receiving -the edges o:E the closure 13 de-Eining
the opening 12 therein. If desired, the closure 13 may be Eormed
in two pieces abutting one another as shown by a broken line 27
' ~I ' ' ! ,
~Z~ 7~L~
in Flgure ~ oE tlle drawings, -to simplify the placement of -the
annular band 25, the :Elanges 26, and the ceramic sleeve 2~ in
the opening 12 of the closure 13. In this modification, the
pipes 16 and 17 he.rei.nbefore described may be relocated in
the ceramic sleeve 24 as seen in Figures 5 and 6.
It will be unders-tood by those skilled in the ar-t tha-t
the ccramic sleeve 2~ Oe the modi:elcation is Iormed of
re:L'ractory materials that readily withs-tand the -tempe:rature
of mol-ten metal and that -the closure 13 is formed Oe refrac-tory
fibers such as aluminum silica-te in a mixture which may include
dolomite, sodium silica-te, pink clay, mineral wool, e-tc. and
a suitable binder material such as a phenol formaldehyde resin.
The closure :13 may be provided with a transverse fold line
so that il; may be Eolded for Shippitlg . See F in Fi.gure 3.
The appa:ratlls disclosed herein makes possible a method o:E
pouring steel o:r other metal in a receivitlg vesse.l such as
an ingot mold, trumpe-t iunnel mold for bottom poured ingots
or tundish boxes for continuous cast,ers without subjecting
the molten me-tal to the normal a-tmosphere and thereby reduces
or eliminates the possibility of products of reoxidation -Eorm-
ing in the molten metal as would otherwise occur. The method
comprises the introduction into the receiving vessel of a known
--10--
,, . . ~ . .. . : .
3L~2~37~
quantity of hexamethylene capable of formlng a gaseous cloud
upon subjection to mol-ten metal ini-tially contacting the same
and acting to purge the normal atmosphere from the receiving
vessel,providing a closure of insulating fiber board or the like
with an opening therethrough which may have a ceramic sleeve in
the opening in the closure and positioning the closure with or
without the ceramic sleeve on the -top o:E the receiving vessel,
sealing the edges of -the closure to the upper surfaces of the
receiving vessel, bringing an outlet port nozzle o-f a ladle
or -the like source of molten metal into engagement wi-th the
opening in the closure or against the upper end of -the ceramic
sleeve, d:Lrecting molten me-tal through said opening or the
ceramic s:Leeve into said receiving vessel to a desired height
therein, addillg a topping of powdered hot top compound, such
as acid t:rea-ted graphite or a similar mate:rial. to the sur:eace
of the molten metal and moving the closure with o.r without the
ceramic sleeve downwardly onto the surface of the molten me-tal
and the hot topping compound thereon and permitting said closure
to move downwardly in the receiving vessel with -the molten metal
when the same is withdrawn therefrom so as to maintain a continuous
seal with the receiving vessel and prevent the in-troduction of
atmospheric air into the receiving vessel and its con-tact with
-the mol-ten me-tal therein.
~z9~s
The horizontally disposecl hea-t resis-tant closure 13 is
preferably -Eorme~ oE low -thermal conductivity re:fractory material
such as inorg~nic fibrous ma-terial, particula-te material and an
organic binder; the inorganic fibrous ma-te:rial being selec-ted
-Erom the group consisting of asbes-tos, calcium silica-te
fiber,aluminosilicate fiber and alumina fiber; the particulate
refractory material belng selectecl from a group consis-ting o:f
.sllicia, alumina, ~ircon, olivine, magnesia, aluminosilicates
and carbonaceous materials; and the organic binder being
selected from -the group consisting o~ syn-thetic resins, natural
resins and carbohydra-tes.
It will thus be seen that a method and appara-tus for
pouring mol-ten metal into an ingo-t mold or a -tundish box or a
continuous caster has been disclosed which is relatively
simple to perform with the use of a relatively inexpens:Lve
apparatus and i.t will be observed that -the apparatus is
formod o~ mater:lals including inorganic :Eibrous materLa:L,
particuLate refractory material and ceramic material which may
be easily discarded and replaced wherl e:roded by contact with
the mol-ten me-tal protec-ted -thereby.
Having -thus described my invention, what I claim is:
-12-
'