DE1508965B1 - Method and device for the continuous casting of aluminum and aluminum alloys - Google Patents

Description

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generic methods and devices (see. Ren, in an economically optimal way

Dr. Erhard Herrmann, manual of the Stranggie- to unite with each other.

Bens, 1958, Aluminum-Verlag GmbH, Dusseldorf, The process provides a solution to this problem P. 322, Fig. 1075), in which a so-called according to the invention before that at the beginning of the Gießvor- If a “short” mold is used, there is a 5-aisle casting cup at such a distance Difficulty with a relatively low meniscus too pouring from the lower edge of the mold that is set ßen, but in the fact that the meniscus height results in a meniscus height at which freezing of the Therefore, it cannot fall below a certain lower limit, avoiding a float in the solidifying melt because otherwise the float when starting the will that then the continuous casting process that concludes the mold freezes inside the mold. io drive floor if the metal feed is continued was one reason why it was customary up to now to be lowered considerably, and that after the start of Abmit the relatively high lowering required for starting the further pouring with a through Verrin meniscus height to continue pouring. When lowering casting, the distance between the inflow nozzle (s) of the casting is reduced Aluminum rolling ingot with a cross-section of a cup Mevon lowered from the lower edge of the mold 800 x 150 mm and above as well as from a press bolt height of 25 to 40 mm above the bottom of the mold (Round bars) with a diameter of 200 mm rand takes place.

and there is hardly any meniscus heights above this. This path taken by the invention to

by about 50 to 60 mm. Utilization of an effective cooling section of the

It is true that it has been around for a long time in the continuous casting strand from only 25 to 40 mm above the bottom of the mold known from aluminum (e.g. French margin accepts that during the tentschrift 1398 526) that an optimal grain structure approach of continuous casting on the strand still has a return of the strand can then be achieved if relatively thick outer layer with relatively long the strand only arises in a very short area of columnar crystals, as has been the case up to now knows about 25 to 40 mm, measured from the lower edge of the mold, even with float-controlled molds, upwards, through the mold is cooled, whereby the 25 This edge layer is however already behaving additional Cooling of the moderately short continuous casting length emerging from the mold through the over-strand in this area during the solidification of the course to continuous casting with a relatively low menis strand contributes. Continuous casting with meniscus height in the sense explained at the outset drastically increase In this area, therefore, improvements have already been made, in that only columnar crystals are distributed viewed, but due to different 3 ° relatively short length in a thinner edge technical difficulties (see, for example, the zone arise. In any case, you get over The risk of freezing the float, as explained earlier, is the vast majority of the length of the cast mers when starting the mold) as practically un- strand compared to casting with a long mold feasible discarded. Instead, you have so far a significantly improved surface quality, and the mold was above the area mentioned if it was interspersed with columnar crystals lined with insulation, if you want to remove the edge areas afterwards, you get called a shorter cooling range for improvement, on the whole significantly less waste. The surface wanted to use the surface of the strand, quality of the strand produced according to the invention and with a constant conventional meniscus height tot is at least as good as with one with worked within the lined area. 40 thermal lining of the mold

However, this known technical route can lead to the strand, with the risk of additional harmful training of surface damage caused by the impact of the lining material on the the lining on the strand. Wide surface of the strand prevented from the start the thermal lining is a secondary closure. There are no difficulties lubricate with a conventional lubricant of 45 more, the strand perfectly along the entire conobes, As is the case with the continuous casting of long bars and a cycle path of the metal with the inner wall of the from ingots with a large solidification interval, it is advisable to lubricate the mold and, if necessary, to because a mold lubricant that is used to replenish the flow lubricant in a known manner from above Metal facing side of the heat-insulating lead, especially since the inner surface of the mold is from the lining would be applied, there the metal temples 50 can be formed evenly and without a set. Also not applicable temperature and is therefore exposed to the equipment and maintenance of a thermally fast decomposed. Furthermore, the lining wears out when the lining of the mold is connected to the mold relatively quickly and must often be objected to with every mold; rather, it is just a one-time investment zein to be replaced. If you also consider the relatively small extent required. Lining only in a given mold 55. The method according to the invention can also be used inserts, it comes to a paragraph on the lower edge without difficulty at the same time with multiple-strand lining. But if you use the lining in the pour.

Embeds the mold, which leads to the different heat- After the method according to the invention let expansion of the heat-insulating material of the rolling billets and pressing bolts made of aluminum lining and the thermally conductive metal of the 60 minium and aluminum alloys (e.g. from AlMn Mold when the mold cools down to shrink and low-alloy AlMg) with a smooth surface gaps between the mold and the thermal lining. to water. The aluminum rolling bars can thus to

The invention is therefore based on the object, sheets of anodized quality are rolled, since the

the two goals, on the one hand a freezing of the stem crystal zone is thin and even and so-

A float in the watering head can be reliably avoided with a relatively low milling depth.

and on the other hand, continuous casting is removed for improvement.

tion of the structure in the edge layers of the cast- Another advantage of the inventive method

nen strand with a low meniscus height is that the tolerance range for

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the casting temperature can be selected further than NEN types of metal, e.g. B. to different buoyancy so far without cold welds or thicker ratios of the swimmer in different Me-stem crystal zones. In pure aluminum tallegierungsschmelzen, be able to adapt, for example, the tolerance range of the casting temperature A particularly simple design of the Mitnehnach 10 5 mereinrichtung is the be extended to 15 ° C of a plurality of the edge above about 10 ⁰ C and down, corresponding to a doubling of the float attacking brackets formed, this area corresponds. Also z. B. with AlMn and when the low-alloy AlMg in a multi-strand caster a smoother surface reduction of the inflow nozzle distance to the bottom as a result of a strong reduction in exudation on the fixed edge of the mold can be set by lowering the inflow nozzles. io compared to the respective fixed mold in front of the casting cup distance to the lower edge of the mold, it is advantageous that the mold can be reduced as soon as the pouring cup carrying the inlet nozzle (s) of the individual floor opposite the lower edge of the mold around Continuous caster was lowered on a common abutment about 50 mm. Support, which can be moved in a timely manner by lowering the casting cup in relation to the vertical direction by means of the lowering of the casting cup distance to the lifting devices distributed along the support, which can be actuated synchronously from a zen lower edge of the mold, alternatively or at the same time. the fixed mold and / or by lifting If, according to the above-mentioned alternative of the mold compared to the fixed pouring cup, the distance between the pouring cups is not reduced. 20 lower edge of the mold by lifting the mold ge-When continuous casting of aluminum or aluminum compared to the fixed casting cup vorgenomumlegierungs-rolling ingot of large cross-section, it is preferably provided, for example, with a meniscus height that allows vertical displacement of the To approach several molds from 60 to 80 mm and to continue casting with such a lifting device that supports the mold from 25 to 40 mm. 25 hen that are from a central control device

In the known device for continuous casting can be operated synchronously.

of non-ferrous metals, from which the invention is based - The invention is shown below with reference to is the pouring cup that carries the inflow nozzle (s), matic drawings on several execution stationary explained in more detail on the co-examples serving as a carrier for him. It shows Killenrand superimposed. 30 Fig. 1 shows a rectangular cross-section Execution of the method according to the invention, a mold filled with liquid metal rens is provided that the float on a continuous caster in plan view, with within Carrier-attached driver device with the mold cross-section an unfavorable solidification longitudinal play is arranged, and that one pulled out between the margin limit 11 and a cheap solidification mold and the lifting device 35 arranged on the carrier are shown in dashed lines, for setting different vertical distances F i g. 2 a side view, partly in section, between the pouring cup and the lower edge of a device for carrying out the mold of the invention is provided. according to the method in the direction of view parallel to the It is already known per se to have a Gießbe narrow sides of a rectangular cross-section container opposite the upper edge of a floating mold,

merless, working without a free metal mirror, at- F i g. 3 the device according to FIG. 2 in plan view, close to the nozzle and with an un- F i g. 4 one in the device according to FIG. 2 pre-interrupted from the nozzle into the mold continued- seen swimmers in side view in a geten Fused artery fully filled mold different from that of FIG. 2 slightly reduced representation, set high; However, this is used, unlike in 45 Fig. 5, the float according to Fig. 4 in plan view, of the invention, to the annular gap between Gießbe- Fi g. 6 one in the device according to FIG container and upper edge of the mold on alternating and 3 provided lifting device in side view Operating conditions throughout the course in the direction of view parallel to the long sides of the codes Continuous casting to adapt (German patent specification kille of the device according to Figs. 1 and 2, 1 140 675). 50 Fig. 7 the lifting device according to Fig. 6 in view

The device according to the invention makes it possible, direction from the right,

not only to change the meniscus height in the sense of the invention, FIG. 8, the lifting device according to FIG. 2, end of continuous casting the float together with F i g. 9 one in the device according to FIG. 1 and 2 the casting cup from the molten metal inside 55 used mold in plan view and to dig a somewhat disguised mold and thus also at the end of the nerter representation together with an associated continuous casting a freezing of the float safe cooling device to prevent. FIG. 10 is a section along line BB from FIG

The lifting device is preferably discrete. 9,

adjustable. This offers the advantage that the operator 60 F i g. 11 shows a section along the line CC of

people of the mold no specific setting dimensions F i g. 9,

need to measure, but only on certain Fig. 12 an embodiment of a lifting device, device assigned to the respective operating situation in a side view for a multiple continuous caster settings need to orientate. able to carry out the inventive

It is advisable to drive between the carrier and 65,

13 the lifting device according to FIG. 12 in

Intermediate member provided to enable the device to be viewed from above,

different operating conditions with different Fig. 14 one for actuating the lifting device

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according to FIGS. 12 and 13 serving central control arrangement broad sides 18 against the narrow sides 16 out

tion in block diagram, 2Vi ⁰ Io the length of the broad sides, no holes

15 shows a further embodiment of a lifting device. The first holes towards the middle

equipment in sectioned side view, have 8% of the broad side length on both sides

FIG. 16 shows the lifting device according to FIG. 15, in FIG. 5 a diameter of 2 mm, the remaining bores

Look over it and find one (in the middle part of the broadside)

17 shows one for actuating the 2.5 mm lifting device. The narrow sides 16 of the mold are

15 and 16 serving central control arrangement designed as L-profiles and cast _{from AlMgSi 5,}

in a block diagram. They are cooled by spray tubes 48.

A feed device 13 rests according to FIG. 2 10. These have two rows of injection holes,

and 3 by means of a cranked carrier 14 and one which are arranged so that the cooling water

Lifting device 15 on narrow sides 16 on one rolling side to the L-profile (indirect cooling), on the other

Ingot mold 17. An approach floor 20 is connected to the exiting mold just below the edge of the mold.

Lowering piston 21 connected. The inside dimensions of the tend strand (direct cooling) is injected. That

In this example, mold 17 is 1020 and cooling water is fed in through a connection 49.

265 mm, so that rolling ingots of about A valve 50 enables the regulation of the cooling water

1000 x 260 mm can be cast. The internal feed.

surface 19 of the mold 17 is smooth here (but can be due to the cooling of the co-

also be vertically grooved) and has a height of kille 17 is achieved that a solidification of the in the

115 mm. ao mold 17 located liquid pouring head in

A casting, an edge region with a rectangular profile covered on the inside with a mold coating according to FIG

_k cup 22 made of gray cast iron can by means of an inflow dashed circumferential line 12 of FIG. 1 and not

ψ channel 23 are charged with molten metal - which would be unfavorable - according to the elliptical

and has two inflow nozzles 24. A float 25 perimeter 11 takes place.

with baffle plates designed as raised points 26 35 The narrow and broad sides of the mold 16, 18 are

regulated in cooperation with inflow nozzles 24 screwed and pinned together. The interior

the metal inflow and closes the nozzles when surface 19 is machined smooth. By means of fastening

the metal mirror in the mold 17 a fixed pen 51, the mold 17 is installed in the device

Peak reached. When moving off, the vehicle is closed.

River channel 23 is expediently arranged horizontally. In the case of the float 25 according to FIG. 4 and 5, cry so that after lowering the pouring cup it consists of 1.5 mm thick black sheet metal and 22 is not too steep. is covered with mold coating, the measuring takes place

With end sections 27 of the float 25 rests on tallaustritt horizontally against the narrow sides.
Brackets 28, which are connected by intermediate members 29 with Before the start of casting with the in the F i g. 2 a cranked carrier 14 by means of a screw device 35 to 11, the casting quake bolts 30 are connected with nuts. Thanks to 22 and the pouring channel 23 expanded and the slots 31, the intermediate members 29 and floats 25 can thus be adjusted in height by moving the support bracket 28, the bracket 28. to the distance between

According to FIG. 6 to 8 are the pouring nozzles 24 and the baffle plates 26 in the lifting device 15 curved by actuating the lever 32. The lifting device 15 is by means of the crank disks 33 rotated, whereby the support disks 33 are brought into the upper position via rollers 34, so that the zen 35 and a table 36 a support 37 of the cast-on to prevent freezing of the cranked carrier 14 is raised or lowered. Hül- float near the bottom of the mold in pants 38, which are firmly connected to the table 36, hem meniscus takes place. As soon as the swimmer and bolts 39 are used to guide the table 36 45 has detached from the support brackets 28 and is thus free and the support 37. The lowering of the feeder can be done by the approach floor 20 or the lowering device 13 must of course be lowered onto secondary piston 21. After the strand done evenly across the sides. This is caused by respectively rolling slabs by about 50 mm, a locking device 40 is reached, which can be used with the feed device 13, i.e. carrier 14, a series of holes 41 forming a scale together with 50 pouring cups 22 and floats 25 with inflow nozzles acts. Before actuating the lever 32, a 24 is slowly lowered until the desired Lever 42 is pressed, whereby the tip of a BoI meniscus height is reached for further pouring. the zens 43 pulled out of one of the holes 41 lowering must be done evenly, what with the help in which she is currently sitting. After the holes 41 have been reached, they can easily be carried out. Is the one you want Position, the lever 42 is released, 55 desired meniscus is reached, the lever 32 is locked. and the tip of the bolt 43 is animalized under the pressure.

a helical spring 44 into the corresponding hole. At the end of casting, the feed device 13

41 inserted and the lever 32 locked thereby. lifted up again to prevent them from freezing

The in the Fi g. 2,3,9 to 11 shown mold can. This happens in one go with the help of the

comprises broadsides 18 from an extruded 60 at 32, which is also the excavation of the float

Hollow profile made of AlMgSi. Cooling water is made possible by connecting 25 from the liquid watering head. By

Keys 45 are fed to a cavity and when the lift leaves the remaining in the channel 23

this through holes 47, which return the cooling water to the residual melt in the furnace or the crucible.

against the broad sides of an exiting strand.

Zen. Due to the water connection on both sides, the system shown in FIG. 2

in the middle creates a jam, which increases the pressure and the device shown in FIG. 3 has the disadvantage that

and thus a stronger cooling in the middle to have to regulate in four, six or more places.

Consequence. In addition, at both ends of the This disadvantage is

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direction of Fig. 12 to 14 avoided. This can be raised or lowered in any direction at will on a frame 52 of a continuous casting can. The watering cup 62 rests by means of a holding rod device put on. The various metal trains 68 on fixed beams 69. The hydraulic guiding devices 13 rest on a single see lifting devices 67 and the beams 69 are designed as a regulating frame support 53 from FIG. 5 carried by a frame 70, which is on the upper Angle iron that rests with the help of four hydraulically actuated part of a housing 71. The pouring channel is that activated pistons 54, which run in cylinders 55, are not shown for the sake of clarity. The Einben and is lowered. The stroke is, for example, directions 67 allow, for example, a stroke of 100 mm. By means of a pump 56 (a hand 100 mm. By means of a pump 72 (a hand pump pump is sufficient) via a synchronizing valve 57 ίο is sufficient) via a synchronizing cylinder 73 the the pistons 54 lifted synchronously. The lowering piston of the lifting device 67 is lifted synchronously, followed by the load on the piston 54, which controls the mold 60 in the desired relative of the oil return into an oil reservoir 58 through a re-high position to the outflow nozzles 63 of the pouring cup regulating valve 59. The frame-shaped support 53 is brought. The mold is lowered can in this way be controlled from a single location by the load on the pistons in the stroke mechanism and can be fixed at any height. lines 67 and controlling the oil return in a

The device according to FIGS. 15 to 17 has an oil reservoir 74 through a regulating valve 75.

Continuous casting mold 60 with variable height, the strand is usually poured into water.

a float 61 and a watering cup 62 with lowers, the water level up to about 100 mm

two outflow nozzles 63. The mold 60 rests on 20 the lower edge of the mold can be brought up. It

two bars 64, the ends of which come with a frame 65, of course, other coolants

are connected. This framework, in turn, is in question as water. It can also be atomized

Lugs 66 with hydraulic lifting devices 67 Use water for direct cooling of the strand.

connected, so that by operating the Hubein- zen.

For this purpose 3 sheets of drawings

Claims (10)

1 2 claims 'Iage' characterized in that the casting F "rather (22) of the individual continuous casting devices 1. Method for vertical continuous casting of resting on a common support (53) Aluminum and aluminum alloys under conditions that are distributed along the support by means of Use of one or more Zuflußdü- 5 lifting devices (54, 55), which of a sen having pouring cup, one in the central control device (56, 57, 58, 59) syn- can be operated simultaneously with the inflow nozzles as flow regulators, in the vertical direction interacting float to be automatically slidable. see regulation of the metal supply, and an 11th device for carrying out the process bottom of the mold at the beginning of the final io rens according to claim 5, characterized in, start-up floor, and with direct cooling of the strand emerging from that for vertical displacement of the mold (60) of the mold , characterized in that several devices supporting the mold are provided at the beginning of the casting (67), which is set synchronously by a central process of the casting cup in such a control device (72, 73, 74, 75) from the lower edge of the mold, 15 are feasible. that there is a meniscus height at which a
Freezing the float in the solidifying
Melt is avoided that then the approach floor closing the mold when continuing the metal supply is continuously reduced, so and that after the start of lowering the further Casting with a reduction in the distance of the inflow nozzle (s) of the pouring cup from the The invention relates to a method for 25 to 40 mm above the lower edge of the mold. 25 vertical continuous casting of aluminum and aluminum 2. The method according to claim 1, characterized in that genium alloys using a one or indicates that at the beginning of the casting process several inflow nozzles having pouring cups, a meniscus height of at least 60 mm above one in the mold with the inflow nozzles as the lower edge of the mold is set. river governing cooperating swimmer for 3. The method according to claim 1 or 2, there- 30 automatic regulation of the metal supply, and characterized in that the further casting of one of the bottom of the mold takes place at the beginning, as soon as the strand is about 5 cm out of the approach floor, and with direct cooling of the out The mold has leaked. strand emerging from the mold. 4. The method according to claim 1 or 2, characterized in that the invention further relates to a pre-identified, that reducing the meniscus direction to carry out this procedure, kushöhe by lowering the casting cup against- During continuous casting of rolling ingots and press bolts the fixed mold is made of aluminum or aluminum alloys will. one strives to have the smoothest possible surface and 5. The method according to claim 1 or 2, characterized in the thinnest possible columnar crystal layer on the Umgekenn, that the reduction of the meniscus 40 fang of the cord is preserved, including an incus height by lifting the mold, intensive cooling of the strand produced is necessary the watering cup is made. is. The thickness of the rolling ingot in particular by 6. Device for carrying out the process machining treatment, z. B. by milling, too rens according to claim 4 with a removing edge layer on a carrier and the amount of it held pouring cup, characterized in that 45 chips should be reduced to a minimum the float (25) can be placed on one on the carrier. In the case of metal with so-called (14) attached driver device (28) anodized quality, which is in the form of metal sheets is arranged with longitudinal play, and that a between or profiles can anodically oxidize without see the mold (17) and the carrier (14) on stripes, spots and the like orderly lifting device (15) for the setting 50 appear, it is also very desirable ment of different vertical distances between that when removing the edge layer of the area of the the pouring cup (22) and the lower edge of the stem crystal zone after a mold that is as little deep as possible (17) is provided. pending machining will be eliminated with certainty. 7. The device according to claim 6, characterized in that this can in principle, for. B. characterized by a high pouring, that the lifting device (15) is dis- 55 speed, i.e. by a high level of lowering secretion is adjustable. speed of the resulting strand, or through 8. Apparatus according to claim 6 or 7, pouring with a relatively low meniscus height in the characterized in that mold can be achieved between the carrier. (14) and the driver device (28) a casting with high lowering speed longitudinally adjustable intermediate member (29) provided 60 easily leads to the strand tearing, in particular is. if it is a rolling ingot. These 9. Device according to one of claims 6 mode of operation is therefore only applicable to a limited extent, namely up to 8, characterized in that the entrainment borrowed for strands of relatively small transverse device (28) of several at the edge of the cut dimensions, e.g. B. from bars or plates. Swimmer (25) attacking brackets (28) 65 formed with a relatively low meniscus during casting is. there is no risk of tearing, even if there are two 10. Device for carrying out the procedure, for example, to produce aluminum rolling bars of a transverse bar according to claim 4 as a multiple continuous casting section of 800 x 150 mm and above. at