DE1583565A1 - Method and device for the continuous production of castings from molten metal - Google Patents

Description

Η981

ALUMINUM COMPANY OP AMERICA »Pittsburgh, Penno / USA

"Method and device for the continuous production of castings from molten metal" _o

The invention relates to a new and improved apparatus and method for the continuous casting of metals and metal alloys. It is particularly concerned with the continuous casting of mechanically and metallurgically sound aluminum and aluminum alloy castings for subsequent processing in the manufacture of forged products "The term" aluminum and aluminum laws "includes aluminum metal and alloys which contain at least 65 $> aluminum"

■■■■■■ «. ■ 1«.

OUUθ 3 8/0 29 8 ⁽

In the case of continuous watering, so far steady gesohaolzenea Metal is introduced into one end of an open-ended, axially relatively short cooling mold, while cooling medium directly against the outside of the cooling mold in sufficient Amount was applied to heat from the neighboring to pull off molten metal and around circumferential solidified walls and outer surfaces of a Srnbryogießling of sufficient mechanical strength and thickness to produce a molten phase or crater of generally conical shape or T-shape can carry in itself, at the same time the casting continuously withdrawn from the exit end or the end of the cooling mold which is opposite the end where the melted Metal is fed continuously »Bs was previously common, cooling media, directly on the outer surface

stepping on the baby caster

from the short cooling form in the axial direction / aneu turn », whereby in the continuous casting process it was applied in such quantities that the inner molten phase of the embryo castings cast in this way was fully * - constantly and essentially in the transverse direction in one plane was solidified, which axially a distance from the exit end the cooling pan had "

Published in the published directed to continuous pouring Literature has also been suggested to

00983870298

Sätzllohe noise ventilation devices must be provided that are calibrated

axially into the interior of the generally conical crater extend the molten phase of the embryo casting to promote heat dissipation from the inside and the rate of internal solidification of the molten phase to accelerate in the crater of the embryo casting · In such proposals, cooled nuclei or Containers made of relatively highly conductive materials recommended moving into the crater of the molten phase of the continuously cast Sabryo cast. stretched *

The invention relates to a method for continuously casting castings from molten metal, which is carried out by

Ca) continuous metal to the sinlafiende an open ended Supplies cooling mold »which is temporarily locked on the opposite find,

(b) the molten metal cools through the walls of the cooling mold and the temporal Sndversohlusses to a SmbryogleSling in the form of a solidified shell generate, the continuous solidified outer side walls and an outer band wall connected to it which rests against the temporal end cap, and in the shell an inner crater old melted

0091 ^ 8/0298

BATH

Has metal phase,

(c) a heat insulating core portion axially in the crater of molten metal phase at a lateral and axial distance from the solidified side wall and Arranges the binding wall of the embryo casting envelope,

(d) continuously the temporal end spaling and the first part of the embryo casting envelope that is therewith is in contact, pulls out in a known manner while continuously introducing molten metal between the core part and the cooling mold, and

(e) continuously supplies coolant against the cooling fora in sufficient quantity to allow a progressive growth of the embryo casting shell and solidification of the molten metal in the crater Bio-manufacture in the vicinity and without contact with the heat-insulating core part and the cooling mold under continuous casting extraction conditions.

According to the invention, a device for continuous casting of castings from molten

- 4 -.
009838/0298

BAD üf.iia.i-.r.

Metal proposed, which has the following parts: an open-ended cooling mold; which are essentially the outer surfaces of a continuously poured and withdrawn from it Foundling defined; a heat-insulating form in direct connection with the cooling form and in a uniform manner Connection therewith and above the same} a core part of the insulating form and the cooling form can be introduced? a device for localization of the outer boundary surfaces of the core part with respect to the heat-insulating form and the cooling form and in axial expansion with it? wherein the outer boundary surfaces of the core part with the molten metal brought into contact v / ground, - which is introduced into the insulating form and the cooling fora, and wherein the Surfaces of the core part made of heat-insulating material exist"

In contrast to the older methods, the present invention is based fundamentally on the use of a heat-insulating means, such as _o B ', a core part - is preferably let movable <- ■ * in the molten metal crater of continuously cast products ^ as well as a mechanism and Process steps for operating and holding the same, which serves to »displace the molten metal in the crater and the solidification

'.-. ■■. 5 - ·. ■

009838/0298

speed to be thermally controlled. You selection and

the use of the heat-insulating device or the core instead of the previously used cooling core or cooling container, in combination with a device for moving the same during start-up and before steady-state Operation of the caster is essentially reversed isothermal solidification gradient inside the continuously cast molten metal crater Products. This replacement has been phenomenal Results achieved because of the use of a thermally insulated Essentially, according to the invention, an increased production output of continuously produced castings has the consequence which are mechanically and structurally sound and are fine-grained »

Further, the inventive continuous molding with the use of metal alloys and in particular in aluminum alloys and similar alloys which have a tendency ausβerθ under AEEN conventional continuous casting conditions and to form sub-oberflächliohe zones which are depleted in the normal constituents, a significant reduction in the depth such zones resulted, which is directly reflected in the depth of the required processing, in order to make an acceptable continuous casting and similar cast parts acceptable for subsequent processing

009838 ^ / 0298

create forged products.

An exemplary door direction for carrying out the casting method according to the invention will now be explained in more detail with reference to the accompanying drawings. This configuration, however, should not be understood in a restricted sense.

Se β eigen ι

Figure 1 shows the boiling end for the molten metal a continuous casting machine in a plan view, which explains an embodiment of the device according to the invention, with which the invention appropriate procedures can be carried out;

FIG. 2 shows a cross section on the plane 2-2 of FIG EU start of a casting process; and

FIG. 3 shows a cross section on the plane 3-3 of FIG SU at a later point in time during the continuous casting process.

It should be noted in relation to the drawings and the following description ₍ that the vertical arrangement and the substantially cylindrical shape of the casting device and the

BAD ORjC.

so that continuously produced castings are not limiting factors, but merely one of the possible devices and methods according to the invention explain"

According to the drawings, a conventional open-ended, Kurzachige cooling form 10, which consists of a relatively A highly conductive material, such as graphite or aluminum, is flanged or otherwise shaped at the inlet end at 12 and is in direct contact Connection with an open-ended, non-cooling, heat-resistant, heat-insulating, laterally closing molded part 14 «Bas commercially available material "Marinite" (heat-insulating Aebest / silicon dioxide composition) has been used successfully for the molded part 14. Other commercially available poorly heat-conducting and heat-resistant materials, such as. Bricks or the like, which are used for lining clay high-temperature metallurgical furnaces, can be used instead

of the "Marinite" part of the molded part 14 are used »

Per mold part 14 can consist of one piece, but it was designed for design and economic reasons found desirable to manufacture it from adjacent, thermally insulating plate points or layers 16,

~ 8 -00'98 38/0298

which are surrounded by a protective support frame or a sleeve 18 which is attached to the inlet end flange 12 of the cooling mold 10. The sleeve 18, which surrounds, delimits and encloses the non-cooling, heat-insulating mold part 14, preferably has a generally channel shape in longitudinal section and is provided with an outwardly directed Endflansoh 20, which as a bearing for. a base plate or a ring 22 made of steel or another metal is used, which is fixed to the flange 20 by means of an arranged around the circumferential series of bolts 26 '(FIG _o I) .. A pressure plate or ring 28 is preferably also at the The inlet end of the outer shell 18 is provided and rests in the vicinity of the flange 20 on the insulating plate or layer 16 =. Hand adjustable pressure screws 50 (FIGS. 1 and 3) which are threadedly engaged with the base plate or ring 22 exert pressure with their free ends against the ring 28 and provide a uniform, compact assembly of the plates or layers 16 within the Sleeve 18 of the non-cooling, heat-insulating molded part 14 safe _o

Opposely arranged brackets 32 made of steel or a similar material are attached to the outer surface of the base plate or the ring 22 with bolts 34 (Figo 1} ,

009838/0288

and parallel spacer bars 36, preferably at least two, each of which carries a pair of Klemmutte.rn 38 and 4-0 on the opposing threaded endons _p create, together with said brackets 32, a unitary structure which is integral with the base ring 22 Connection is »

A cross shaft 42 is rotatable in aligned bearing openings stored in the holders 32 and carries a pinion centrally 44 »which is attached and with the help of a locking screw or otherwise attached. This pinion meshes with a rack to be described later 46ο An exact position of the cross shaft 42 between the brackets 32 is secured by a pair of rings 48 fastened with screws ensured which are attached to the shaft 42 and on the inwardly facing surfaces of the brackets 32 ο A hand wheel 50 (Fig. 1 and 2) is on one Extension of the cross shaft 42 attached and has a Disc 52 with a through opening 54 (Fig. 2), which is concentrically aligned with each of a series of similar openings 56 (Figs. 2 and 3) which extend through the adjacent bracket 32, which is spaced therefrom. In FIG. 2 it can be seen that an angled blocking pin 58 can be inserted through the opening 54 into one of the openings 56

'' - 10 «
009838/0298

can, via the handwheel 50, the transverse shaft 42 and the pinion secure against movement relative to the axially aligned mold parts 10 and 14 au. Let a support frame on the transverse spacer chains 36 attached and consists of i «spaced transverse bars or Rahnenteile 60 »the bit protruding mounting pins 62 are equipped »which open into entepreohende openings extend in the rods 36 (Pig. 2). The protruding Find the pins 62 may nit threads for the reception of nuts (they are not sloped and at the vertical Arrangement of the casting device shown not essential) be provided "which would allow an attachment of the holding device to the spacer rods 36" The side parts 60 of the holding device are firmly in the Level of their outermost and from the spacer bars surfaces facing away from Bueammenhalten »and swar« it With the aid of a transverse rail or plate 64 'which carries a low friction bearing plate 66 which see in sliding contact It the side of the rack 46 facing away from the pinion 44 is located (flg. 3). It is clear that in the case of the Meohanienue described so far, a rotation of the transverse shaft 42 duroh operation of the handwheel 50 a reciprocating motion the rack 46 results.

Figures 2 and 3 explain the implementation of the

009838/0298

BATH ORIGINAL

inventive method essential parts of the structure. It can be seen that a roughly cylindrical or box-shaped container »the core part or displacer and is designated in its entirety by the reference numeral 68, is firmly attached to the end of a port set of the rack 46, namely to the the side opposite the pinion.

The heat insulating core or displacer 68 is concentric or central to the common longitudinal axis of the cooling mold IO and the heat-insulating molded part 14 attached to it are subordinate to »by precise adjustment and Fixing of the transverse shaft 42 and the pinion 44 arranged thereon in relation to the plane and axis of the rectilinear movement of the rack 46 »that with the pinion combed

The heat-insulating core or displacer also preferably has a hollow part made of steel or a other metal on "the one at both ends and also transverse plates or stiffening parts 70" 72 or "in between. 74 which are attached, for example, by levers or the like, to the inside of an uninterrupted wall or side walls of the drum-shaped or box-shaped sleeve of the displacer 68 ", you

- 12 -009838/0298

Toothed rack 46 is arranged feet on the displacer and preferably has a cross-section reduction below the teeth, this cross-section reduced part extending through aligned openings in the intermediate plates 72 and. 74 extends (Figo 2 and 3)? where they are welded or otherwise mechanically fastened. There are also guide rods 76, which are fastened to the external plate 72 and extend upwards from there, and extend into correspondingly arranged openings in the spacer rods 36 and adjusting screws 78 (FIG. 2) wear at the end of the bursting, threaded end »with which the amount of axial displacement of the displacer 68 within the mold parts 10 and 14 can be limited»

The main structural feature and the pivot of the success of the invention lies in the use of a non-cooling heat resistant and largely thermally insulating outer wall at the core portion or displacer 68 _o This outer casing or wall consists vorteilhafterweisβ from an end plate 80 from "Marinite" or a similar nloht-cooling heat-insulating material »which is attached to the adjacent end plate 70 of the displacer 68 in a suitable manner, such as zi), by a central» externally operated bolt 82 _o a case

- 13 Q0S & 39 / Q298

washer 84 is under the head of the Bolsen 82, in order to distribute the contact pressure between the central lowered part of the plate 80 and the near outer facing surface of the end plate 70 of the inner neck of the displacer 68, which is in contact therewith »exercised will.

The end plate 80 is preferably designed in such a way that it protrudes laterally beyond the inner, uninterrupted side wall of the core part or displacer 68, to create a possibility of contact with an outer, non-cooling, heat-insulating side wall 86 surrounding the inner sleeve, which has a pressure ring or a plate 88 made of steel or the like carries on the side facing away from the end plate 80 _o The plate 88 is preferably in contact with the free ends of the bolt 90, through which a bridge can be exercised and which is in a threaded connection with a to the outside extending flange 92, which in turn is attached to the side walls of the displacer sleeve 68, whereby a uniform structure of the heat-insulating outer side and end surface of the concentrically arranged displacer 68 is created »thermocouples 94 (? ig _o 2) or similar temperature sensing and / or - measuring devices are in at least three axially separated nth planes parallel

, _: , U. * 009938/0298

sur transverse plane of the end plate 80 of the displacement 6Θ provided? thereby reducing the thermal conditions within the Can be announced before.

In the case of preventive operation of the so far described continuous operation of the invention, a movable ßndTersohlusskühlblock 102 within the otherwise open stepping end of the KUhIfom 10 in the latter sealing arranged »as indicated by the dashed line in figure» if the Schwlmer 68 either rolls constantly is sucked out of the isolated Fomenteil 14 or sweok's space saving is in an intermediate position »as shown in Figure 2 (this position is called The initial position is taken into account) »is consummated» su pouring metal through the open end of the heel part 14 » that the cooled fora 10 is turned away "from a suitable source from sugef" for example by an or ■ Several feed channels 96 »around the KUhIfor« 10 above the dashed position of the Kndversohluöplatte 102 (Fig. 2) to su a beatinate height within the isolated fore part Tem by means of the feed channel or feed channels 96 on Ullen.

KUhlaittel »as s.B. Water or something like that »is against that KUhI-shape 10 tone Xussere of a perforated main

15 -

BATH

away

98 is supplied in a sufficient amount to dissipate heat from the molten metal supplied in this way within the mold parts 10 and 14 and to solidify an embryo casting 100, which is defined by a circumferential and self-supporting sleeve within the axial length of the cooling mold 10 and a end plate 102 communicating with the sleeve; this sleeve contains a substantially centrally arranged liquid "crater" phase made of non-solidified material, which sloh axially into the ferments !! 14 extends where the Metallbesohickung remained fluid

A movement of the end plate 102 from the seal with the cooling mold 10 to an axial distance, as shown in the figure with solid lines, with uninterrupted regulated supply of molten metal to the insulated mold part 14 and a controlled flow of coolant against the cooling mold 10 and the now exposed The solidified shell of the embryo casting 100 corresponds to the conventional continuous casting practice _e

The preferred implementation of the method according to the invention is that in an otherwise conventional continuous casting operation as described above, the displacer 68 is axially through the crater

16 00 983 8/0298

bath

158356b Λ *

the molten phase of the embryo casting 100 is guided to a position shown in FIG. 3, which corresponds to the position which is maintained during the continuous casting according to the preferred implementation of the invention. A comparison of FIGS. 2 and 3 shows that the solidification curve 104-, the molten metal crater limited radically altered by the lowering movement of the displacer 68 in the position shown in Figure 3 position wirdj the displacer now extends axially through the insulated mold part 14 in the cooling mold 1O ₉ and by an amount which is approximately half as large as the axial length of the cooling mold 10 is ₀

By the use of the core member or displacer 68 _f as described above, _s is provided a substantially scaled or narrow feed channel 108 ,, which is defined by the Quersehnittsflache between the inner wall of the heat insulating mold 14 and the outwardly wärmeiBOlierenden wall of the displacer 68, which are both above and mostly within the cooling mold 10 (Fig. 3). This is in contrast to the flat cross-section of the mold parts 10 and 14 in the absence of a displacer 68 “It is precisely this reduced cross-sectional area of the feed channel 108 in connection with the the insulated walls of the insulated

= 17 ..
001838/0298

Λ1

Form 14 and the displacer 68, which increases the Casting speed as described above allowed

example

The one described above and in the accompanying drawings illustrated device was for continuous casting

of 63 9 5 om thick castings made from the 2214 aluminum alloy

^ Wherein a casting speed reached for use, which was twice eo large as it was obtained with the same but Gießlingzusammenßetzung and with the same device without displacer 63 "Me composition of the 2214-Aliminiuial8glerung is 0.8 wt. ~ £ silicon, 4 ₈ .4. GeWo -Φ copper _P 0.8 wt .- ^ Manganese, 0.4 wt _o - # Magnesiumi the rest consists of aluminum ,

It is'zu-observed that the solidification line substantially to the shape dee immersed end block 80 of the wärmeiaolierenden Verdrängere 106 (Fig _{3: 0)} follows, which is in contrast sur hardening curve 104 dea lower crater of Figure 2 is _β, it is in figure 3 at the Point 110 you can see * that the feed channel 108 widens slightly at the point of entry into the embryo casting at 110! this position © lies approximately in the contact plane between the

.18 00 38 38/029

KUhIfons 10 and the heat-insulating mold 14ο It is assumed that the molten metal dissolving pad fed to the feed channel 108 is subjected to a maximum drastic cooling and a maximum heat extraction at an elevated temperature, namely in the case of it borrowed simultaneously with the feed surface 110 with an enlarged cross-section, and the molten metal cooled in this way follows the surface of the heat-insulating displacement blook 80 ": whereby a uniformly falling temperature gradient to the center is created over the outer surfaces of the sling to be divided

Am cast from 2214 aluminum alloy with 65.5 cm, the It was poured on this quietly and continuously, was mechanically and structurally sound; a fine grain structure and a reduced depth of superficial and sub-surface ions lined zones and was essentially free tone faulty spots (cold bhuts). All these Properties are a more uniform and directional heat dissipation ssuzuschreihen that transversely over the Broad or perpendicular but usual longitudinal axis of the forms 10 and 14 of those continuously cast according to the invention Products also take place essentially within the axial length of the Küalfosra 10. The shortened axle length the seized metal phase within the crater of

'. 19 009838/0298

to

Figure 3 also indicates the fact that the temperature of the molten metal is in the transverse plane through the crater is more uniform and the solidification is noticeable takes place more uniformly inwards towards the center of the thus molded products than it does with longer conical ones Craters is the case, which have so far been encountered in the usual continuous casting process, as shown in Figure 2 were at least partially explained.

Sio implementation of the continuous casting process and the operation of the device described above can thereby interrupted that the supply of the molten Metal interrupted to the isolated molded part 14, the displacer 68 out of contact with the one in the crater of the just cast products brought remaining molten metal and the axial withdrawal of the cast product 1OO continues, while preferably continuously pouring coolant against the cooling mold 10 until the molten metal is completely solidified in the crater, whereupon the coolant flow is interrupted and the product 100 from the pouring device according to the invention is completely can be pulled out.

- 20th & QS838 / 0298

Claims (1)

ZA Claims Process for the continuous casting of castings from "a molten metal" in which one continuously feeds metal to the inlet end of an open-ended cooling mold, which is temporarily closed at the opposite end, so that the molten metal cools down through the walls of the cooling mold and the lateral end connection around an embryo 3? orm of a solidified shell to produce 'the circumferential solidified äuasere side walls and an associated outer end wall ₉ has abutting against the temporal end closure, and having in the shell an inner crater with geschmolze ner metal phase, characterized in that _p reacting a wärnieisolierendes core part axially in the crater of molten metal phase at a lateral and axial distance from the side wall and end wall of the solidified Embryogießlingshülle _f continuously arranges the temporal end closure and the first part of Embryogieß "· 1ingahülle, the thus exploiting in contact friend pulls out in a known per se Yfeise while kontinuier-Iic5h molten metal is introduced between the core part and the cooling mold "and continuously sufficient coolant to the cooling mold in a manner known per se in βloh 0 09833/0298 ÖAD Amount leads to a progressive growth of the embryo casting sleeve and a solidification of the molten metal in the crater in the vicinity and without contact with the heat-insulating core part and the cooling mold to ensure under continuous casting conditions _a 2. A method according to claim 1, characterized in that the molten metal is fed through an inlet to a thermally insulating Jmold part which is arranged adjacent and in unit with the open-ended cooling mold, the molten metal being supplied in sufficient quantity to fill the cross-section of the cooling mold ,, and that said heat-insulating part axially out of the heat-insulating mold part in the cooling mold and into the molten aluminum crater of the embryo casting sleeve ₉ so that it laterally and axially from the side and end walls of the erabryo casting sleeve to the heat-insulating lorment part and the cooling mold has a distance " 3 η method according to claim 1 or 2 »characterized in that the molten metal used is aluminum or an alloy which contains at least 65 $ aluminum" - 22 "
^ '§138 / 0288 Zl 4o Torrlohtung for carrying out the method according to claim 1, "calibrate an open-ended cooling mold, the iq essentially the outer surface of a continuous defined castings to be poured and to be withdrawn therefrom, a device for the supply of molten metal into the cooling mold and for the withdrawal of the continuously cast casting, characterized by a wämeleolierende form (14) in direct connection with the Kühlfora (10) and in uniform connection therewith and above the same, a core part (68) which can be inserted into the heat-insulating mold (14) and into the cooling mold (10) is «a facility for the localization of external Limiting surfaces of the core part (68) with respect to the Cross-section of the heat-insulating form (14) and the cooling form (10) and in the axial direction so that the outer limiting surfaces of the core part (68) with the molten metal (108) are brought into contact can, which of the insulating form (14) and the KUhI form (10), is removed »with the surface of the» core parts consists of insulating material » 5ο device according to claim 4, characterized in that that devices (44, 46) for the relative axial back and reciprocation of the core member (68) with respect to the heat insulating mold (14) and the cooling mold (10) is provided - 23 - (709838/0298 it a mü am *. die MtmtfaM & m (Ίβ)% & * on the outer boundary surfaces of the above-mentioned displacer Whom axial BmtvmUwg T & Gfimaet, «ö au« f «fltopt -lm% daee outer ajciale I ^ treekwsg
before ^ em JSintrittseiicl « ¥ orriciitmig after a ^ ter examination 4 <> ä # r 5 t that a fuel supply (fS) for im the Jiitie of the Kiüilform (10) and 7, before vt oatung naoii one of the AnaprUcJie A ₉ 3 or 6 _t 4a * by means of knowing that the core part {68) has a smaller cross-sectional area than the transverse surface of the cooling mold <10) "and in all exceptions of the same , whereby they are arranged in a uniform manner axially within the heat-insulating JNsrm, (14) XBt <.