DE2005626A1 - Process for the continuous casting of metal - Google Patents

Description

3 HANNOVER, ST 6

3rd February 1970

TELEPHONE (OSII) I * 8I

Chemical Corporation

Unier's characters:

276/63

Process for the continuous casting of metal

The invention relates to a method for the continuous casting of metal, such as light metal, in particular Aluminum and magnesium. The invention is particularly applicable on a horizontal and vertical continuous casting from a metal reserve with continuous lubrication and direct chill casting of such metal blocks.

Casting molds of this general type are known per se. It is also known that a certain control the heat transfer rate in the mold for successful continuous casting is required. The control of the rate of transition in the casting mold was previously on the change in the thickness of the message agent film by changing the conveying medium flow rate limited. Such control is often ineffective or

009836/1353 ~ ² ~

or even so, because of a great flow of compassion of the oil, which is believed to have made the walls of the The casting mold is better insulated and thus the tendency to form limestone joints is reduced, a deformation the thin screen-forming embiyonalon blook bowl causes resulting in ribbing or scarring in the surface leads. A control of the heat transfer rate The casting mold is necessary because of the overwhelming opinion, because of the high heat transfer rates in the mold to cold folds on the surface Blockes can lead. As it turned out that a

Controlling the flow rate of the lubricant being ineffective, a technique has evolved to reduce cold wrinkles which consists of accelerating the continuous casting puffiness so that the angle of formation of the resulting shell becomes larger. Very often, however, the casting speed must be limited in order to avoid the formation of porosity due to cracks or shrinkage, and in particular to a speed which favors cold inclusions. In US Patent 2,983,972 a Y _e lot rfabren described for determining the casting speed, so that cracking or cracking does not occur. Separation is another very serious problem that occurs with directly cooled ι (DC) casting and is obviously due to insufficient noise

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BAO ORIGINAL

Transition is caused as well as by an inadequate upstream cooling above the wetting line of the cooling liquid.

The present invention relates to horizontal and vertical continuous casting, with which it is possible To produce blocks that have both high internal and surface quality, in other words, it is oöglioh to manufacture blocks that are essentially free ▼ on are cold locks and free from segregation.

According to the invention that is achieved that a axially aligned to the casting mold insulated feed container is used, which no longer has an overhang than about 3 mm over the inner wall of the mold, and that a casting speed of the metal to be cast is set in such a way that the upstream heat conduction distance, measured from the wetting line of the absorption liquid, is up to about 2.5 μm towards the container extends.

In this way, the speed of heat transfer in the conductive casting mold during casting by controlling the casting speed in one area

regulates that the solidification line of the surface of the ingot from the upstream conduit in the Have the meeting between the conductive casting mold and the insulated container is.

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This has been found to be achievable if the casting speed and the upstream lei The spacing is derived from the following equation:

uot - ^ cm (I Op (Vt ₁ ) + qJ / fc _p (t ₀ -t _q ) + q]]

In the UCP »upstream line

distance In FuB, «i,« = temperature control table to

casting alloy in feet / b, U * speed in feet per hour, C s heat capacity of the alloy to be cast in

Btu / lb ° F,

t * quenching temperature in the cooling zone ⁰ F, t ^ β initial temperature ⁰ F,

t _Q «temperature of the liquid metal in the upper

Part of the container ⁰ F, Q = latent sonic warmth in stu / lb. is.

It is desirable to sieve the upstream located conductor spacing up to about 12.5 mm to extend to the storage container. The optimum would be achieved if the upstream conductor spacing substantially equal to the length of the casting mold plus the distance between the end

the casting coke and the liquid wetting line of the Absobreokflttselkelt would be. A precise control of this

009836/1353

However, the point could be difficult and should be the upstream conductor spacing scattered into the storage container, problems could arise. For this reason, the process is practically controlled in such a way that that the upstream conductor spacing is on a Value of about 2.5 cm is maintained, preferably at a value of about 12.5 mm.

The temperature of the wall of the casting mold can be measured to determine whether the casting speed and the like of the upstream conductor spacing meet the desired ratio. If the casting is liquid-cured aluminum, the conditions are generally satisfactory if the wall temperature of the casting mold is maintained at a value which is at least about 10O ⁰ P (56 ⁰ C) higher than the inlet temperature of the coolant and not higher than about 300 ⁰ F (168 ⁰ C) as the inlet temperature of the coolant. The coolant can be used as a quenching liquid or separate sources are available for coolant and quenching liquid. Not only can the casting resistance be regulated in order to keep the mold wall temperature within this range, but it can also be regulated in order to bind the temperature of the mold wall to temperature fluctuations that are more than about ί 25 ⁰ F (14 ⁰ C) Per

Fluctuation deviates when the speed of the temperature

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raturwecfasels is about 0.5 to about 10 variations per inch of length of metal being cast. A temperature deviation greater than H ⁰ C per temperature rise would indicate that there are cold blooms. Instead of regulating the casting speed to control the casting mold wall temperature and thus maintaining the desired ratio between casting speed and upstream conductor distance, it is also possible to use a special casting device by which the position of the liquid wetting line of the quenching liquid is changed, whereby the upstream conductor distance is regulated, and the wall temperature of the casting mold is prevented by more than - 25 ⁰ F (H ⁰ C) to fluctuate, when the rate of temperature changes per inch length of the cast material is in the range of about 0.5 to about fluctuations.

The invention will now be explained in more detail on the basis of exemplary embodiments which are shown in the drawing are.

Pig. 1 shows a side view similar to FIG

a continuous casting device according to FIG

present invention, Fig. 2 shows a longitudinal section of a continuous casting

Vorriobtung according to the invention, Fig. 3 shows a Grapbisobe representation that the

Relationship between casting speed and

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Tilt removal for a typical aluminum alloy,

Fig. 4 is a longitudinal section of part

a casting device showing the upstream conductor distance and the effect on the quality of the block if the casting speed is too low, «5 let a longitudinal section through one part a caster showing the upstream conductor distance and the effect on the quality of the block when the gas velocity is the minimum for bed results is. · 6 Is a longitudinal section duroh a <n, feil a casting device, woleber αie upstream conductor distance eeigi and the effect on the quality of the block if the pouring speed in the rake best quality reaches the maximum and

YLg. 7 is a lsngssohnitt by part

a Gieevozrlobtung showing the preferred stromau.fwftrte conductor distance and the effect when oils gas velocity is bocb on the quality of the block to.

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009836/13 S 3

The speed of the Värueübergangs ia the thermally conductive casting mold during casting is regulated by controlling the casting speed in a cd mode, such that the solidification liuie on the surface of the Block from the upstream line in the area of the collision between the heat-transferable casting mold and the insulated container. The upstream located conductor distance or distance UCD is the distance up from the wetting plane of the direct quenching serving coolant and the solidification line on the Obex surface dee block, which by the direct extension enter alone. Mathematical constraints have been taken to make UOD determinable, and in the process found that the heat transfer rate of about O,

* o 'IOD extends to the bottom of the tank, can be changed to a maximum, where UCD is about 12.5 to 25 tmn downstream of the Connecting parts between the container and the casting mold lies, oha <* that any noticeable adverse effects are to be determined in the quality of the bloke. The length ▼ on the crater front on the surface, which is caused by the Cooling takes place via the OieSkokille alone, up to the Connection point between casting mold and storage container, is the eieekokiilen length or MAL. A Temperaturüberwacbungselemeat or a Vandler can be arranged in the wall of the GIeS mold and connected to a Tbermoelernent

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so that the pouring consistency can be controlled in this way can that siob a constant heat transfer rate durob results in the wall of the casting mold and thus a uniform blook surface. Another or different control device is created by using a special quenching water that is separated from the cooling of the casting mold and which can be moved upwards as well as downwards, whereby the UGD solidification line in the casting mold can be changed. It has been found that casting devices, whose insulated reservoir has a large ring-shaped Has opening axially to the annular opening of the thermally conductive casting mold are aligned and at where the insulated gate container protrudes inwards from the inner surface of the casting mold between 0 and 3 mm, produce the best results. That is special wiobtig at casting speeds of around 15 era per minute Or less·

As already mentioned, the present invention is concerned with controlling the rate of heat transfer in the casting mold durob change in the upstream conductor spacing and the effect of the surface quality of the block on this transition speed and the upstream conductor spacing. In the figures the drawing, in which the same parts are identical is shown in Fig. 1 of the prior art.

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From this it is assumed that 11 is an open ended isolated Reservoir is, which at 23 by a significant amount inward over the thermally conductive casting mold 14 protrudes. A SobmiermitteIzufUbrung 12 directs lubricant into the interior of the casting mold by means of a Slit or a wick 24 a. A suitable coolant, usually water, or some other liquid enters the casting mold at 13 and flows out of it out to hit the screen forming blook at 15. Liquid metal 16 is contained in the storage container 11 and is supplied via a line not shown.

Various surface shops are shown in Flg. 1, 21 examples of cold inclusions, 22 segregations and 25 ulfolds, grains and the like. Although there is no unanimous agreement among experts on how such damage occurs, the explanation given below is the generally accepted one. At low meal speeds is the liquid / Festgrenzfläobe 1 (if alloys are used, which have a temperature range between the Llquidustemperatur and the solidus temperature, then, this means that at this interface about 90 i> of the metal solidified) in Fig. By the line 17 indicated. Under these conditions there is a high

Heat transfer speed and a slow withdrawal speed of the casting a solidification sheet with

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an angle 26 of about 90 °, which is an offset bridging between the protruding TeS, 23 of the container and the giefiling forming front 17 causes, which creates cold insoles 21 along the entire length of the GIeQ-linga

If the Gieögesobwindigkeit increased, moves the SiOB Kratarrungsfront pseudostebilen in a condition in the position of "the line is indicated duroh 18, in which the surface of the block flatter Kalteinscblüase up i

can point, but the possibility that outsourcing 22

arise, increases. In many large-format blocks, cracks and cracks occur when the casting speed is higher than that which results from the solidification front 17. Attempts IaIteineoblasse by Erhöbung de · ölstroaes durob line 24 lu voreiligem. Bringeth ¹ · Generally eu deeper Ealtelnsoblüsaen, scars and! Wrinkle formation if dl · Internal quality good 1st of the block, the casting speed a Vert can be increased up eu {in which the solidification front wanders to eur line 19 vox. Under these conditions, however, there is a likelihood of very natural precipitations 22, because the thin solidification shell 27 is often at a temperature higher than the solidus temperature and is porous enough for liquid metal to heat up permanently through it. Normally, the heat transfer to the casting mold itself is not sufficient to form a shell that is thick and cold enough

1st to prevent outsourcing, even if for

009836/1353 -12-

βίαβα maximum heat transfer is ensured.

Flg. 2 inclines a sliding device according to the present invention.

The insulated container 11 is concentric to the casting mold 14 and has an inner annular wall, which runs parallel to the center line of the casting mold 14. Liquid metal 16 is fed to the container via an opening which is not shown. The solidified metal 20 becomes withdrawn from the sliding mold via known devices which are not shown. The edge 25 of the inner wall of the Beb & lters 11 extends sloh naob inside to the center line feu by an amount that is between 0 and slightly more than about 3 am. Sin Soblltz 24 is to initiate a Sobaiereittels 12 in the miniscus, which is in the local metal forms below the edge 23 of the container and on the inner wall of the continuous casting mold 14 is provided. A temperature converter 29 is used to measure the wall temperature of the GieSl'okille intended. The Upstream Conductor Distance (UOD) is shown as the distance that is from the plane direct water absorption of the block at 15 and dor Br- " sterrongsfront on the surface is limited when the ' Värveübe ^ gang O is. The solidification front of the upstream located heat conduction should niobt more than about 2.5 on streamed from the edge 23 of the insulated container and preferably in a range of about 12.5 mm from the Cant «23.

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The following mathematical relationship for UCD, or upstream conductor distance, was derived using unidirectional heat transfer . Eb can be shown that for a certain. Alloy and Absobreoktemperatur the UOD is a puncture of the casting speed and the casting temperature. For different alloys, a change in the thermal diffusivity or in the melting point will also change the UOD. The temperature conductivity is directly proportional to the thermal conductivity of an Ä

Alloy and inversely proportional to the product of the diobe and the heat capacity of an alloy, consequently

the theoretical upstream conductor distance

UOD given durob UOD * -oC In (jo_ (t -O + Q / C „(t -O + QH

^ fT IL P ° 'JLP ⁰ H JJ

upstream conductor distance in the UOD is in puss

J ^ u temper a door leit "abl eu cast alloy

in Puö ² / h,

U »Oie8gescbwittdigk0.it ia Puss per hour, I

The thermal capacity of the alloy being cast in Titu / lb ° P,

t «Absohreoktemperatur in the Küfclzos.e ⁰ P, t-j_ η SiskarruQg Temperatur ⁰ P ₉ t ₀ β The temperature of the liquid metal in the upper

Part dee Bebaltere ° f,
Q. * latent enamel mass in Btu / U> is ·

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This ratio is plotted in FIG. 3 using the properties of typical aluminum alloys. It should be noted that the length of the mold and the upstream conductor distance are not identical are. The upstream conduction begins where the direct Absobreok water hits the surface of the Blookes wetted. When the water flow is low, it develops often a steam bath that connects the water to the blook wetted to 2 1/2 cm or more beyond the actual point of impact of the drainage water. It is therefore important maintain a steady flow of water so a constant level of solidification to the upstream .Conditions with sufficient volume and sufficient Speed is maintained so that formation eiues steam exposure is reduced to a minimum. Vereuobe have shown that the diet of the upstream Heat conduction is independent of the block size.

The Pig. 4, 5, 6 and 7 show in partial sections (It is only the inner wall of one half of the casting mold according to FIG. 2 grjzei / jt) as the heat transfer rate through The wall on the desk is controlled according to the present invention can be. Fig. 4 shows conditions under which the heat transfer rate 3ebr is low, because the upstream pitcher distance (UCD) did that Solidification frozen text by direct cooling at 30 shifted upward beyond the edge 23 of the container. This The condition is that the casting speed for a certain alloy is too low, the casting temperature is too low.

009836/1353

door and a wetting line of Absobreok liquid at 15. These conditions cause giants and wrinkles and cold inclusions 21 on the surface of the GIeB line. The wall temperature of the mold measured by the Stampers turwandler 29 In Pig. 2 is within 10O ⁰ F

C) the inlet temperature of the coolant. The location of the Solidification front 50 due to direct absorption in the upper one Heat conduction increases progressively in the PIg. 4, 5, 6 and 7

below, which illustrates the effect of progressively higher glide rates.

Pig 5 shows the maximum value for the upstream heat conduction at which a block with a good surface can be produced The solidification front in these pigures is caused by changing the casting speed. The Vandt temperature of the mold in Pig. 5 measured by the transducer 29 is typically 100 to 150 ⁰ P (56 to 34 ⁰ O) above the inlet temperature of the coolant.

Pig · 6 shows the minima! Value upstream Wärmeleitentfeirnung, with which Blöoke good surfaces can be produced · The solidification front 30 has also In Pig. 5 saturated position due to an increase in the casting

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eo speed moved further, so that the mold length alone (MAI *) is not more than about 2.5 cm, preferably not more than 12.5 mm. The Vaadteaperatur of the mold reaches its maximum with about 30O ⁰ F (168 ⁰ O) above the inlet temperature of the coolant measured with the converter 29 in Flg. 2. Any gas velocity that creates an upstream thermal conduction distance equal to or between the positions in Figures 5 and 6 will produce surfaces with very shallow perturbations. When aluminum is cast the surface-borne faults have a depth of about 3 fflm and mostly less than 1.5 mm. Casting processes of a still known type produce surface defects of 12.5 mm and deeper. The wall temperature of the mold increases continuously to the value for Flg. 5 is given to the value given for Fig, 6 is when <-] le casting speed increases. Since there is a constant thermal resistance between the temperature converter in the wall of the mold and the coolant in the mold, the difference between the converter temperature and the water inlet temperature in the mold is directly proportional to the heat transfer rate through the W / j and the mold at this point.

The temperature of the tfanö of the mold is not only within the specified range, but is stable within - 25 ⁰ F (H ⁰ C) the equilibrium tempera door, which forms in this area. The Glelcbgeviohtetemperatus can

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Blob naob and after In the range of low frequency, db with 5 vibrations per foot of blook length or less «Sonical changes that are characteristic of cold folds, db 0.5 to 10 changes per 25 mm blook length, must be within - 25 ⁰ F. (16 ⁰ C) lie so that the KaItfaltangetiefeη at most 3 mm, preferably less than 1.5 mm, make up.

If the sieve speed is increased further, it moves the solidification front 30 closer to the water wetting line 15, as shown in FIG. In this case

the embryonic or thin shell 27, which was formed by the cooling in the casting mold, shrinks back from the V / and the mold and moves through a zone in which a slow cooling takes place before the solidification guide 30 is reached . In this case, the length of the mold alone is MAL longer than the zone of good heat transfer between the blooksobale and the wall of the mold, because the shrinkage has occurred. The thin shell 27 is often at a temperature which is higher than the solidus temperature of the alloy to be cast, and it is therefore porous, and segregation and exudation 22 take place. The thin base 27 is also deformed very much because of the accumulation of the lubricant and sometimes also by mechanical means, so that bioboil coatings or corrugations 25 form. The wall teuperatuxea of the mold measured by the Fandler 29

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Iq 71g. 2 are typically not higher than 30O ⁰ P (168 ⁰ C) above the blooming temperature of the water in Flg. 6 »In other words, the wall tempering door of the mold reaches a maximum when the speed increases and then runs out when the speed increases.

As stated above, the position of the solidification front 30 can be controlled by controlling the wetting line of the Absobreok flttesigkelt can be controlled, either by a movable pipe for the absorption water or by controlling the discharge angle of the liquid from a water pipe. if This is done, you can get a constant upstream thermal conduction distance, which is never determined by the fact that the casting accuracy, which would have to be kept constant, is maintained and the thermal conductivity of the alloy is maintained

and the GIe8'temperaturen. The following examples explain the inventor.

Example I.

A rod of round cross-section made of the alloy 6063 and with a length of about 23 µm was cast vertically using a thermally conductive Gleßkolrille of 25 mm length and a wall dioke of approx. 9 mm made of aluminum and / a container made of the insulating material Marlnite,

009836/1353

Trademark of the company-Johns-Maαν11le Company, which a stiff plate material made of asbestos fibers and an inorganic binder and which protruded 1.27 mm approximately inward beyond the thermally conductive recess of the mold. Alloy 6063 is made up of $ 0.20-0.6> silicon, $ 0.35> iron, 0.10 i> copper, 0.10 1> manganese, 0.45-0 0.9 # magnesium, 0.10 % Chromium, 0.10 # zinc, 0.10 56 titanium and other elements of 0.05 # each »but a maximum of 0.15 #,

Bast aluminum. The coolant water had a temperature of about 12 ⁰ C and flowed at a rate of 26 gallons per minute. The CrieBtemperatur of the alloy was 680 ⁰ C. The liquid metal was oingoletiet via a lateral öffnuug into the container. At a casting speed of about 89 mm per minute it resulted in a corrugated and torn surface. Me Vendtemperatür the mold was 51-101 ⁰ P (about 28 to 5J ⁰ C) above the Eirlaßtemperatur of water. The calculated upstream heat-conductive refinement was about 34 mn., Weighed. at a distance of about C ₉ 5 c / m between the outlet opening of the casting mold and the wetting line through the cooling water, the length of the mold is about 2.5 mn. The poor surface is therefore based on too little heat transfer in the mold, which is due to the fact that the upstream WLrleitentfernunf; was too big.

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009836/1353 ßAD ORIGINAL

At the same gas flow rate with an increased gas velocity of about 10 on per minute and with all other factors left unchanged, the wall temperature of the oil rose to 111 to 126 ⁰ P (62 to 90 ⁰ C) above the inlet temperature of the water. The surface of the casting was smooth with extremely fine protrusions. The calculated upstream heat conduction distance (UCD) for these conditions was about 31 μm, while with a distance between the exit of the mold and the water wetting line of about 6.5 mm the calculated position of the solidification front on the surface of the block due to the direct cooling 1, 2 mm below the 3-point of contact. If the casting mold and the container were twelve o'clock, which in turn resulted in a mold length of about 1.2 m? results. These conditions correspond approximately to those in FIG. 5, where the thermal conduction route located upstream is approximately its maximum

has useful value.

Thereupon the walking speed was increased to about 10.5 cm per minute. All other factors were kept constant. The Wandtenrperatur the casting mold rose n zwieohen 73 and 81 ⁰ C above the inlet temperature of the water euf door tempera ture *. The surface was smooth with extremely fine protrusions. The calculated upstream heat exchanger for this Geechwinc'igVreit was about 25 mm and the calculated mold length alone was about 6 mm. The

009836/1353 BADOR ₁₆ -NAU

speaks of a case that »wipes out the maximum useful Heat conduction treoke (Fig. 5) and the minimum useful heat conduction treoke (Fig. 6).

Example II

A rod about 31 cm long, square in cross section, was cast vertically from 7079 aluminum alloy at a casting rate of about 5 µm per minute. The alloy has the following composition: $ 0.30 silicon, $ 0.40 Elsen, 0.40 to 0.80 # copper, 0.10 to 0.30 # hanger, 2.9 to 3.7 & magnesium, 0 , 10 b? .S 0.25 # Chrcir, 3.8 blB / ,, 8 # zinc, 0.10 f> titanium, other elements each ru 0.03 # »iötotal but not more than 0.15 #» remainder aluminum, length of the casting mold was 5 cm and the casting temperature

was about 698 ⁰ C. The calculated upstream WärmeleitMtreoke was about 43 mm, the water wetting ^ line was about 6.5 mm below the GießkoklllenaustL'itts, so the calculated mold length DVSS alone etwn 14 mm long was. The container protruded from the inner wall of the casting mold by an amount of about 1.5 mm. The resulting block surface was extremely smooth, free from any cold folds and had only very little segregation. The temperature of the casting mold Ward was up eüwa 170 to 1QO ⁰ C above the Einlaßtemperatuj? of the Y / acisers. This example corresponds to the? of Fig. 6, in which the upstream

009836/1353

located conductor distance or conductor path in the hub dee
acceptable minimum! value.

Example III

An ingot was cast as in Example II above, but using a casting mold length
about 83 am and a calculated mold length alone
* v; n about 46 am. This results in a surface that is very

showed strong segregation and was unbrewable for further processing. This course is shown in FIG. 7. The upstream conductor distance is too short and the length of the cable alone is too long. The wall temperature of the mold amounted to 174-203 ⁰ C above the EialaBtemperatur of Yasser.

Example Γ7

A block of alloy 7039 about 13,000 in length and with a diameter of? of about 13.4 mm became horizontal using a * thermally conductive GieOkok.llle of a length of about 18 mu and one arranged concentrically to it Cast container from marinite. The container e: cstreokte over the inner edge of the mold by about 1.2 am into the GieSV.okille. The KUbimstrom was 60

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009836/1353 ORiGINAL BATHROOM

Gelions per minute, and the pouring temperature is 676 C. The following table shows the calculated upstream conductor distance, the calculated mold length alone and information about the top and bottom conditions at the top and bottom for several pulling speeds.

Table 1

Qitegesobvin- calculated calculated diuity UOD IUL ooi / min. on cm

surface

above

below

8.9 5.5 - 0.5 SE * and
Corrugation severely cracked 10.1 2.5 + 0.5 SE SE 11.4 2.5 + 0.8 SE S3 12.7 2.0 + 1.0 SE SE ♦ 5.2 1.8 + 1.5 ΓΕ corrugated 20.5 1.5 + 1.8 SE corrugated

♦ SE »Light scratches

In the case of horizontal continuous casting, the upper surface is normally less easy to cast than the lower surface, and this was also the case in this case. In a Gie3gescbwia <3ig- kei t of 8.9 per minute on the lower Fläabe was heavily cracked · In a OieBgeschvindigkeit 10.1 to 12!, 7 ctn per minute were the upper and lower surfaces in jeOetn

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Fall well. Bel (HeSgeeobwindigkeiten of 15.2 and 20.3 cm per minute, the lower surfaces were slightly corrugated, which is due to the thinness and the length of the sieve-forming Blocksobale during quenching, and to the inclusion of lubricants In the previous practice in this 1st. Type of alloy and blook size with a long casting bowl and a closed storage container with various speleological holes and slits, the bottom surface of the block is always very heavily affected by cold folds when the casting speed drops below 15 * 2 cm per minute

15t2 otn per minute, the cold inclusions in the conventional prairie are smaller, but then inner leaps set limits. The aluminum alloy 7039 θntbat1 0.30 # Sl.Ii-3lum, $ 0.40> Elsen, £ 0.10 copper, 0.10 to 0.40 # manganese,

J:, 3 to 3.3 tons of magnesium, 0.15 to 0.25 £ chromium, 3.5 to 4.5 $ '& ink, 0.10 i » Ti.tan, other elements each 0.05 ^, at most £ 0.15 total »Heat Aluminum.

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Claims (1)

Claims 1. A method for continuous casting of metal and for controlling the heat transfer during casting in a directly cooled continuous casting mold with an insulated supply container for the metal »characterized in that an axially aligned container 11 is used which is no more than about 3 mm over the VJan3 the casting mold ä vorotebt and a casting speed is maintained, such that the upstream Wärraeleiterentfernung measured from the BenetsungsLinie "5er quench off up to a distance of about 2 1/2 cm of the container to extend. 2. The method according to claim 1, characterized in that 6eß Gießgösohwiadigkeit and upstream Y / ärmeleitorentfarnung correspond to the following equation: (a) TJOX. - ^ m J ^ p (Vt ₁ ) ₊ g] / [o _p (vy + Q] J Elder distance in feet in aer TJCD strooaufwSrto,
a Thermal coefficient of the to be cast Alloy in feet per hour, a casting speed in feet per hour, -26 · 009836/1353 C »heat capacity of the alloy to be cast in Btu / lb ° F, t μ Absobreokt temperature in the cooling zone ⁰ F, t ^ a solidification ^{temperature 0} F ₉ t _Q - temperature of the liquid detail ita upper Part of the container, Q, latent heat of fusion in Btu / lb. is. 5. The method according to claim 1, characterized in that siob the upstream four-way ladder distance to stretched to about 12.5 mm towards the container. 4. The method according to claim 1, characterized in that the upstream heat conductor distance is essentially equal to the length of the casting mold and the distance between the end of the casting mold and the wetting U.nie the liquid that is used to quench. 5 · Ve 7. · Fahr en according to claim 1, characterized in that the temperature of the wall of the Oießko ⁿ -ille is measured in order to determine whether the casting flexibility and the upstream heat conductor distance correspond to the desired ratio. 009836/1353 BAD 6. Method na oh Anepxuoh 5 _f daduxob characterized because the Oleßkllle consists of fltteelgkeltegektthitem Aluolalum and the Lokiiienwand is at a temperature which is at least about 56 ⁰ C higher than the inlet temperature of the coolant. 7. The method as claimed in claim 6, characterized in that the temperature of the wall of the glass mold is kept at a stroke which is not ^{more than about 168 0} O above the temperature of the coolant. 8. Method naob Anepruoh 6, daduxob characterized that the Küblflüeeigkeit then as Abeobxeokfltteaigkeit is used. 9. The method according to claim 5, characterized in that the Crießgesoh Speed is controlled so that the temperature of the wall of the casting mold does not ^{fluctuate more than -25 0} F (H ⁰ C) when the speed of the temperature fluctuations per inch length of cast material in the range from about 0.5 to about 10 fluctuations . 10. The method according to claim 5, characterized in that the position of the wetting line of the quenching liquid is controlled to adjust the upstream gel- -28- 009836/1353 genes Wärmeleiterstreoke that the temperature of the mold wall F (14 ⁰ C) varies no more than about + 25 ^0, if the rate of temperature fluctuations door per inch length is cast material in Bereiobe from about 0.5 to about 10 swings. 009836/1353 Blank page