EP3077138B1 - Method for producing castings from a metal melt by means of casting - Google Patents

Description

The invention relates to a method for the casting-technical production of castings from a molten metal according to the preamble of claim 1.

Such a procedure when casting castings is from the US 5,704,413 A known.

A fundamental problem when casting castings from a molten metal is to perform the mold filling with the molten material so that it comes as little as possible air and Oxideinschlüssen in the casting. In addition, in many applications, a particular course of solidification is sought in order to achieve a structure formation which satisfies the respective requirements for the distribution of the mechanical properties.

Especially when casting Al alloys is added here that the melt should get as quickly as possible from the melting tank or the casting container into the mold. In this way, alloy components are prevented from reacting with the ambient oxygen and forming hard oxides. At the same time, temperature losses during casting should be minimized in order to ensure optimal microstructure formation. These requirements are offset by the risk that during rapid filling of the melt considerable turbulence in the melt flow and gases are included in the casting, causing the Training an optimized structure in the casting is obstructed.

Particularly in the field of casting of parts required for the construction of internal combustion engines, such as cylinder heads or crankcases, from a light metal melt, in particular an aluminum-based melt, a low-turbulence "quiet" filling of the respective casting mold is particularly important. This will minimize the amount of oxides and other contaminants that will float on the melt volume to be filled into the mold and otherwise enter the mold during casting. In order to achieve this, a large number of variants of the so-called "tilt casting" have been developed in the past.

A common feature of the known Kippgießverfahren is that the mold is filled via a docked to them melt container by being rotated with the melt container from a starting position in which the melt container is filled with the melt to be cast, about a pivot axis in an end position, so that as a result of this pivoting movement, the melt flows into the mold.

At one of the EP 1 155 763 A1 known variant of Kippgießens a mold is constructed with upward facing sprue on a base plate and then rotated with the base plate by about 180 ° about a horizontal pivot axis until the sprue side of the mold facing down. Subsequently, a casting container, which is filled with a sufficient to fill the mold melt portion, with its spout opening docked close to the sprue side of the mold. The casting mold is then rotated together with the casting container adjacent to it by about 180 ° about a horizontally oriented pivot axis, so that the melt flows from the casting container into the casting mold. Once the inflow process has been completed, the casting container can be removed from the casting mold. Processes of this type are also referred to as Rotationsgießverfahren because of the wide pivoting path.

From the DE 10 2004 015 649 B3 Another method for tilting is known, are cast with the components of light metal, in particular of aluminum alloys. In this method, the melt is poured in the head casting in a located on the longitudinal side of a mold cross run. The mold is first tilted at an angle of 45 ° to 70 ° about its horizontally oriented longitudinal axis. Thereafter, the filling of the liquid melt in the cross-flow begins until about one-fifth of the melt required for the casting of the component is filled in the cross-section, without the melt already flows into the mold cavity of the mold. Then, with continuous refill of melt, the mold is rotated from the tilted position to the vertical such that the melt flows into the mold cavity along a mold wall.

From the DE 10 2008 015 856 A1 is another variant of a method for casting light metal components according to the Kippgießprinzip known. In this method, the melt is poured into an assembly associated with the mold. From this module flows during a tilting movement of the mold melt in the mold cavity. By the casting mold is pivoted starting from an end position by means of an associated casting machine in a starting position of up to 90 ° about a horizontally oriented pivot axis and by the mold is then displaced in a range of 0 ° to 90 °, geometrically demanding components with good Forming the structure during short cycle times during solidification.

From the DE 10 2010 022 343 A1 Finally, a method for Kippgießen of components is known in which in a first step, a mold defining a mold cavity for receiving a molten metal and having at least one Gießtümpel, from a basic position with upwardly facing sprue in a first pivoting direction about a first pivot angle in a first pivot position is pivoted. Then the mold is prepared for pouring a new casting, where it is cleaned, optionally sized and finally filled with casting cores. Then, the mold is pivoted in a second, the first pivoting direction opposite pivoting direction. It passes through the basic position and is pivoted to a second pivot position in which the mold has a second pivot angle with respect to the basic position. Then, the at least one pouring basin is filled with a liquid molten metal intended for casting a component. Subsequently, the one mold is pivoted together with the pouring basin in the opposite direction in the basic position such that the liquid melt between the second pivot position and the basic position laminar flows into the mold cavity of the mold. One advantage of this variant of tilting casting is that the pouring basin is arranged relatively far away from the operator and thus the heat radiation acting on the operator is comparably low. At the same time, this well-known method for tilt casting with shorter cycle times and thus higher application rates should allow the casting technology production of components in high quality.

Against the background of the above-described prior art, the object of the invention was to provide a method for the casting production of castings, in which a further optimized mold filling and a concomitant optimized solidification process, an optimal quality of the castings is guaranteed.

According to the invention, this object has been achieved by completing the steps specified in claim 1 when casting castings from a molten metal.

In a method according to the invention for the casting-technical production of castings from a molten metal, a casting mold is accordingly used, which is pivotally mounted in a casting machine about a horizontally oriented pivot axis and thereby defines a mold cavity respectively forming the cast part to be cast and a mold cavity delimiting on one side thereof A cover, on which at least one filling opening is provided for introducing molten metal into the mold cavity, a reference side wall, which collides with the cover, which surrounds the cover Mold cavity bounded on its one side with wall surfaces in which an axis parallel to the pivot axis extending main plane of the reference side wall is set so that their orientation is approximated the means of orientations of the wall surfaces, each extending in a direction parallel to the pivot axis direction, and a Floor having its bottom surface associated with the mold cavity images the bottom end of the casting.

In addition, a tundish is used according to the invention, which is at least partially open on its sprue for pouring the molten metal into the tundish and a colliding with the sprue side and a bottom of the tundish over which the filled in the tundish molten metal in the casting from the tundish in the mold flows off.

According to the invention, the tundish is then arranged on the mold in a first step such that its spout side abuts the lid of the mold and the bottom of the tundish is associated with the reference side wall, wherein the sprue of the mold and the open portion of the spout face at least intersect each other.

Then, the mold is pivoted to a pouring position in which the main plane of the reference side wall with the bath level of a molten metal portion to be filled into the tundish forms an angle β1 which is smaller than 180 °, and the bath level of the into the Tundish to be filled molten metal portion is located below the filling opening of the mold.

Subsequently, the tundish standing in the pouring position is filled with the metal melt portion which is sufficient for filling the casting mold.

Finally, the casting mold with the tundish arranged on it is pivoted about the pivot axis into a pivoting direction, in which molten metal flows from the tundish into the casting mold as a result of the pivoting action and the gravity effect, wherein the pivoting is continued until an end position is reached in which the mold is filled with molten metal, and wherein between the main plane of the reference side wall and the bath level of each contained in the tundish metal melt portion each included angle ß1 is at least always smaller than 180 ° until the melt flowing into the mold meets the bottom of the mold.

With the method according to the invention, a considerable shortening of the pivoting path is achieved compared with conventional rotational casting methods, in which a pivoting travel of 180 ° is usually covered. This leads to a significant time savings compared to these methods.

At the same time compared to the conventional Rotationsgießverfahren as well as compared to the conventional Kippgussverfahren in which between the starting position, in the docked to the mold from the melt container still no melt in the Casting runs until the end position in which the mold is completely filled, usually a pivoting of up to 110 ° is covered, achieved a significant improvement of the mold filling process and, consequently, the casting result. Thus, in the case of the procedure according to the invention, the kinetic energy which is supplied to the melt contained in the tundish in the course of the pivoting movement is reduced to a minimum. Turbulences in the melt contained in the tundish are thus avoided. Accordingly, the number of oxidic and other inclusions that reach the melt in the tundish via the surface is minimized.

This is achieved in that for carrying out the method according to the invention, the pivot position of the arranged from casting mold and arranged at her, serving as a melt container tundish combination is selected in the starting position so that after the required for filling the mold metal melt portion is filled, the bath level of the molten metal portion with the main plane of the reference side wall includes an angle ß1, which is smaller than 180 °.

According to the invention, this angle β1 is respectively measured between the main plane of the reference side wall and the free surface of the virtual bath level until the molten metal portion is filled. As "reference side wall" while the side wall of the mold is referred to, which, when the tundish is docked to the mold, is adjacent to the tundish next. "Main plane" of the reference side wall is then an imaginary plane passing through a parallel to the pivot axis of the mold extending direction vector and a second direction vector is spanned, which is aligned on the one hand normal to the pivot axis and its alignment on the other hand corresponds to the means of orientations of also to the pivot axis normally positioned vectors, which are applied to those wall surfaces which extend in each case parallel to the pivot axis.

The angle ß1 is selected according to the invention by a corresponding pivoting of the mold / tundish combination for the Eingussstellung so that it during the filling of the required molten metal portion in the serving as a melt container tundish pivoting of the combination formed from the mold and tundish so long smaller than 180 ° remains until the melt hits the bottom of the mold. This means that in the process according to the invention, the melt to be cast in the course of pivoting and its associated inflow into the mold as long rising flat against the determining the position of the main plane inner wall surfaces of the reference side wall until it reaches the bottom of the mold. Similar to a gently rising against a shallow rising beach swell thus occur in the reaching into the mold melt at most minimal turbulence.

Consequently, in the course of the pivoting according to the invention, the casting mold is flooded particularly smoothly and quietly by the melt entering the casting mold as a result of the pivoting movement and the force of gravity. The casting is built according to the invention with increasing pivoting starting from the reference side wall in Mold cavity of the mold gradually until the end position of the pivoting path is reached and the mold is completely filled with melt.

Surprisingly, it has been shown that the flooding of the casting mold as a result of the procedure according to the invention takes place so quietly that oxides and other impurities present on the melt bath in the tundish remain as far as possible outside the mold cavity of the casting mold, without the need for special measures. In such molds, in which a recess is provided in the region of the cover for receiving a serving as a feeder for the casting casting melt portion, the oxides and impurities accumulate accordingly in a near-surface region in which they pose no danger in terms of the quality of the casting , In this way, the occurrence of inclusions in castings produced according to the invention is reduced to a minimum. Structural or apparative measures, such as the arrangement of a restraining sword, a filter or a sieve in the region of the filling opening of the mold, or the like, it is therefore not necessary. The invention thus leads not only to a significant time savings over conventional Rotationsgießverfahren, but also to improved product properties of the resulting castings over such castings, which are produced by conventional Kippgussverfahren.

Another advantage of the invention is that as casting a open to its sprue side during the filling and panning process tundish of simplest geometric design can be used. This results in respect of the specifications according to the invention in each case a well achievable pouring position, in which by means of a conventional ladle the respectively required melt portion can be filled into the tundish.

The filling opening provided in the cover of the casting mold can be designed for the method according to the invention so that the filling can also be effected in each case in a direct flow from those sections of the casting mold which are far away with respect to the filling opening. D. h., The filling opening is optimally not limited to a small surface portion of the lid, so that the melt enters the mold in a concentrated, fast-flowing flow, but rather designed so that they seen in plan view of the lid from the Covers parallel to the lid-oriented cross-section of the mold cavity of the mold as far as possible. This can also be achieved by allocating each individual fill opening or a specific section of a large common fill opening to the individual sections of the casting mold distributed over the cross-sectional area. For this purpose, a plurality of filling openings can be superimposed on one another in such a way that they merge into one another in their cutting areas and thus form a filling openings branched into two or more sections. The aim here is that the filling opening is maximally large, to allow the simultaneous entry of a large volume of melt into the mold in a quiet flow while avoiding local flow velocity peaks.

The quiet mold filling can also be supported by the fact that the pivot axis about which the casting mold is pivoted extends through or near the bottom of the casting mold. By this with respect to the mold eccentric, offset in the direction of Gießformbodens arrangement of the pivot axis of the slope and, consequently, the kinetic energy is further reduced, with which the melt enters the mold.

Due to the optimized casting results and minimized casting times, the inventive method is particularly suitable for mass production of cylinder heads and crankcases for internal combustion engines, the highest demands are placed on their mechanical and thermal suitability. This shows the advantages of the procedure according to the invention, in particular, when an aluminum-based light metal melt is used as the casting material.

The tundish can be either permanently connected to the mold or held releasably by means of suitable pressing on the mold to carry out the method according to the invention. The latter embodiment has the advantage that the tundish, for example, for cleaning or replacement can be easily separated from the mold. At the same time by a sufficient holding force secure sealing of the joints, at which the tundish abuts against the mold, ensured and even if due to heat or wear the mating contact surfaces of the mold and tundish no longer fit perfectly with each other. As a device for holding the tundish at the Mold are particularly suitable hydraulically operating pressing devices that can generate high Anpresse- and holding forces in a small space.

As in view of the desired evenly calm inflow of the melt into the mold, it proves to be particularly effective if the tundish has a bottom which is flat on its surface facing the molten metal. Optimally, the flat bottom surface is aligned such that it is in a horizontal position at the earliest at the time when the melt flowing into the casting mold meets the bottom of the casting mold.

When casting castings having a well-defined, optimally flat top and bottom surfaces, such as cylinder heads or crankcases for internal combustion engines, where the mold accordingly has two parallel outer surfaces on the outside of the lid and bottom, this can be ensured in that the bottom surface of the tundish forms a right angle with the bottom of the mold.

The tundish can be arranged and aligned in a particularly simple manner on the casting mold if the outlet side is open over the height and width of the trough space delimited by the tundish. This embodiment has the additional advantage that the pending in the tundish in a mold in which a plurality of sprues or gates are present in the lid to be distributed over the melt in the mold Metal melt portion during pivoting over a large width runs evenly against the lid of the mold and accordingly flows evenly into the existing there openings of the mold.

The amount of oxides and other contaminants that are drawn when pouring into the molten metal portion filled into the tundish can be minimized by also pouring in the stream which is as calm as possible. This may be assisted by forming on one of the molten metal facing sides of one of the closed sidewalls of the tundish a rising starting from the tundish bottom in the direction of the upper free edge of this side wall starting surface against which the molten metal is directed when pouring the molten metal into the tundish , The melt of melt which strikes the thus formed inclined surface is deflected with the removal of kinetic energy in such a way that it spreads over a widened front onto the melt already present in the tundish, so that the intensity and depth of the turbulences inevitably arising therefrom are minimized. Depending on the way in which concentrated the pouring stream meets the run-up surface during pouring, it may be expedient to make the run-up surface concave, concave or curved in a concave manner.

Taking into account the above summarized proposals of the invention has been found to be particularly suitable, a tundish whose tub space has a cuboid basic shape, wherein the Mold associated pour spout and the top of the tundish are open, while the run-up surface is formed on the opposite side to the spout side inner surface of the tundish.

Practical experience shows that optimum casting results are obtained, in particular when casting cylinder heads and crankcases for internal combustion engines, if the angle β1 included between the surface of the bath level of the melt portion filled in the tundish and the main plane of the reference side wall is between the surface of the bath level before pivoting. 160 °.

The filling of the casting mold can take place via a distributor channel system formed on its lid or upstream of the lid, if this is considered to be expedient from a pouring or fluidic point of view. However, the particular advantages of the method according to the invention are particularly evident when two or more gates open on the cover as sprues, through which the melt flows during pivoting directly into the mold cavity of the casting mold. Here it has been found that due to the particularly quiet filling, which is ensured by the invention, it is also possible without any problems to directly flow to the lid when it is formed as a lost mold core from a molding material.

Accordingly, the method according to the invention is particularly suitable for casting cast parts in casting molds that are completely or at least partially so-called Core package of a variety of particular molding material preformed casting cores are composed. Such molds are particularly suitable for the production of filigree castings with a variety of internal channels, as they are needed for the construction of internal combustion engines.

The inventive method when pivoting the mold with the tundish disposed thereon between the Eingussstellung and the end position completed swing angle is typically in the range of at least 110 ° and up to 160 °, which turned out in practice pivoting angle of 120 - 150 ° as particularly probat to have.

Fig. 1

eine in Grundstellung geschwenkte Gießmaschine zum Gießen von Gussteilen in seitlicher Ansicht;

Fig. 2

die Gießmaschine gemäß Fig. 1 in einer Ansicht von oben;

Fig. 3

die Gießmaschine gemäß Fig. 1 in Ausgangsstellung mit an ihr angeordneter Gießwanne in seitlicher Ansicht;

Fig. 4

die Gießmaschine gemäß Fig. 1 in Eingussstellung in seitlicher Ansicht;

Fig. 5

die Gießmaschine gemäß Fig. 4 beim Eingießen von Schmelze in die Gießwanne in seitlicher Ansicht;

Fig. 6-8

die Gießmaschine gemäß Fig. 1 in verschiedenen Schwenkstellungen in seitlicher Ansicht;

Fig. 9

die Gießmaschine in der nach Abschluss der Schwenkbewegung erreichten Endstellung in seitlicher Ansicht.

The invention will be explained in more detail with reference to a drawing illustrating an exemplary embodiment. Each show schematically:

Fig. 1

a cast in the basic position casting machine for casting castings in a side view;

Fig. 2

the casting machine according to Fig. 1 in a view from above;

Fig. 3

the casting machine according to Fig. 1 in the starting position with arranged on her tundish in side view;

Fig. 4

the casting machine according to Fig. 1 in pouring position in lateral view;

Fig. 5

the casting machine according to Fig. 4 when pouring melt into the tundish in a lateral view;

Fig. 6-8

the casting machine according to Fig. 1 in different swivel positions in lateral view;

Fig. 9

the casting machine in the end position reached after completion of the pivoting movement in a lateral view.

The casting machine G has a bearing plate 2 mounted in a frame 1, which is pivotable by means of a pivot drive 3 about a horizontally oriented pivot axis HS. At home position ( Fig. 1 ) located casting machine G, the support plate 2 is aligned horizontally.

On a mounting surface 4 formed on the upper side of the carrier plate 2, a casting mold core 6 - 11 composite casting mold 5 is constructed as a core package of a plurality of well-known molds for casting, for example, a cylinder head, a crankcase or an engine block for an internal combustion engine. The molding material constituting the cores 6 - 11 is a mixture of a foundry sand, optional additives and a binder which is solidified by a chemical treatment or heat supply to provide the necessary dimensional stability. Of course, individual cores or parts of the mold 5 may also consist of other materials in order to use them repeatedly. Similarly, in the mold 5, not shown here cooling iron or the like may be present to a to cause directional solidification of the filled into the mold 5 melt.

The mold shown here for clarity only in a rough detailing comprises a bottom 6, side walls 7,8, which form the lateral outer end of the mold 5, a cover 9 and within the mold cavity 5 bounded by the mold cavity 10 casting cores 11, the depict channels and or cavities in the casting to be cast. The bottom 6 and the side walls 7, 8 may be produced, for example, as casting cores made of molding material or as a permanent casting molding made of a metallic material, such as a heat-resistant steel material or a copper material. However, in view of the releasability of the casting to be cast in the casting mold 5, only the cover 9 typically consists of molding material, whereas the base 6 and the side walls 7, 8 are designed as permanent moldings.

From its upper side, a trough-like recess 12 is formed in the cover 9, in the bottom serving as feed openings 13 ends, via which the mold cavity 10 of the mold 5 can be filled with melt.

The casting machine G additionally comprises a pivoting and positioning device 14 likewise mounted on the support plate 2. By means of the device 14, a tundish 15 can be located between a waiting position in which it is located outside the region which, prior to the casting process, builds up the casting mold 5 the support plate 2 or after completion of the casting process for removing the mold 5 is needed, and a Eingussstellung be pivoted, in which it is arranged with its spout 16 on the outside 17 of the lid 9 fitting.

The open on its spout 16 and top O, made of a refractory material tundish 15 defines with its bottom 18, two mutually parallel, along the bottom 18 extending longitudinal side walls 19,20 and a rear wall 21 a tundish space 22. The rear wall 21 extends it parallel to the open spout 16 between their associated ends of the longitudinal side walls 19,20 and has at its the tundish space 22 associated side a contact surface 23, starting from the flat, the tundish 22 associated bottom surface of the bottom 18 in the direction of the free upper edge of the Rear wall 21 rises obliquely.

In its use position, the tundish 15 is held by the device 14 on the casting mold 5 in such a way that the casting mold 5 bears tightly against the associated contact surfaces of the cover 9 of the casting mold 5 with the respective free end faces of the longitudinal side walls 19, 20 and the bottom 18.

During assembly of the mold 5 is the support plate 2 with the mold 5 constructed thereon in the starting position. The swivel angle ß2 about the pivot axis HS is equal to "0" in this position.

After the mold 5 is constructed on the support plate 2, the device 14 sets the tundish 15 with its spout side on the cover 9 of the mold 5 (FIG. Fig. 3 ). The Device 14 holds the tundish in this position on the mold 5 until the casting process is completed.

When placed on the mold 5 tundish 15 which is in this position to the bottom 18 of the tundish 5 next nebenbart arranged side wall 7 of the mold is the reference side wall, which is crucial for the determination of the pouring position in which the tundish 5 is filled with melt. On its side assigned to the mold cavity 10, the side wall 7 has wall surfaces 24 which depict molding surfaces on the associated lateral outer surface of the casting to be cast. Each of the wall surfaces 24 has a specific orientation with respect to the pivot axis HS, which can be indicated in each case by a vector VW applied to the respective wall surface 24 and aligned in a direction normal to the pivot axis HS.

In order to determine the pivoting angle β 2, by which the casting mold 5 with the tundish 15 must be pivoted from the initial position into the pouring position, a virtual main plane HE is laid in the side wall 7, which extends on the one hand parallel to the pivot axis HS and on the other hand is aligned, their orientation is approximated to the mean of the orientations of the wall surfaces 24 indicated by the vectors VW, each of which also extends in a direction parallel to the pivot axis.

The swivel angle ß2 to which the mold 5 after docking of the tundish 15 in the example shown here counterclockwise about the pivot axis HS from the in Fig. 3 shown starting position in the in Fig. 4.5 is shown pivoted, is now chosen so that between the top of the still at this time still virtual bathroom mirror BS of the filled into the tundish 15 molten metal portion S and the main plane HE of the reference side B included angle ß1 is less than 180 °. In the exemplary embodiment illustrated here, this angle β1 is, for example, 135-165 °, whereas the swivel angle β2 is in the range of 110-160 °, in particular 120-150 °.

In this case, when determining the swivel angle β2, it is additionally taken into account that, when the casting mold 5 and the tundish 15 are pivoted in the pouring position, the bath level BS is below the throat 13 of the casting mold 5 which is located deepest in the lid 9 in this position.

After the combination formed from the casting mold 5 and the tundish 15 is pivoted into the pouring position by the angle β 2 determined in the above-described manner, the molten metal portion S is filled into the tundish 15 by means of a conventional ladle 25. The molten metal used here is an aluminum casting alloy, as is customarily used for casting parts for internal combustion engines. In order to ensure a quiet, low-vortex filling of the tundish 15, the casting steel 26 emerging from the ladle 25 is directed against the contact surface 23 of the tundish 15. The incident there beam 26 is redirected with the withdrawal of kinetic energy in the direction of the bottom surface of the tundish 15 and thus meets in a comparatively gentle, distributed over a greater width Flow on the already existing in the tundish 15 melt S.

After the end of the filling of the tundish 15, the mold 5 is pivoted with the tundish 15 in the clockwise direction back toward the starting position. With increasing pivoting flows more and more melt S in the mold cavity 10 of the mold 5, until finally when re-reaching the end position (= initial position), the molten metal portion S is completely filled in the mold 5. Excess melt volume is absorbed by the recess 12 in the lid 9. The melt volume collected there at ready pivoted mold 5 serves as a feeder to compensate for the material shrinkage occurring in the course of solidification of the melt.

The selected for the Eingussstellung swivel angle ß2 has been adjusted in accordance with the invention that the angle ß1 between the bath level BS and the main level HB of the side wall 7 is always less than 180 °, until the flowing into the mold 5 melt S against the ground 6 of the mold abuts. This adjustment ensures that the melt S runs at an acute angle flat against the wall surfaces 24 of the reference side wall (side wall 7). In this way, a smooth, layered filling of the mold 5 is achieved, which forms optimal conditions for the formation of a uniform structure in the finished casting. Foaming on the melt is prevented as much as possible. Also due to the quiet filling process, the resulting casting is largely free of inclusions or other damaged areas. Soiling and Oxides which could cause such inclusions accumulate in an upper layer of the feed volume SV formed in the recess 12 of residual melt S, whereas in the tundish 15 at best small remnants remain, which can be easily removed.

REFERENCE NUMBERS

ß1

Angle enclosed between the top of the bath level BS and the main plane HE

ß2

swivel angle

BS

Bath level of existing in the tundish 15 molten metal S

G

casting machine

HS

swivel axis

HE

Main plane of the reference side wall (side wall 7)

S

molten metal

SV

Speiser

O

Top of the tundish 15

VW

the orientation of the wall surfaces 24 indicating vectors

1

frame

2

support plate

3

Rotary actuator

4

mounting surface

5

mold

6

ground

7

Side wall (reference side wall)

8th

Side wall

9

cover

10

mold cavity

11

casting core

12

recess

13

gates

14

Pivoting and positioning device

15

tundish

16

Ausgussseite

17

Outside of the lid 9

18

Bottom of the tundish 15

19, 20

Longitudinal side walls of the tundish 15

21

Rear wall of the tundish 15

22

Gießwannenraum

23

Contact surface of the tundish 15

24

Wall surfaces of the side wall 7

25

ladles

26

pouring stream

Claims (14)

1. Method for casting cast parts from a molten metal using

   - a casting mould (5) pivotably mounted about a horizontally aligned pivot axis (HS) in a casting machine (G), the casting mould (5) defining a mould cavity (10) shaping the cast part to be cast in each case and having

   - a lid (9) delimiting the mould cavity (10) on its one side, on which at least one filling opening (13) is provided for feeding molten metal (S) into the mould cavity (10),

   - a reference side wall (7) abutting on the lid (9) and delimiting the mould cavity (10) on its one side with wall areas (24), into which a main plane (HE) of the reference side wall (7) running axially parallel to the pivot axis (HS) is placed in such a way that its alignment is approximated to the average of the alignments (VW) of the wall areas (24), which also in each case extend in a direction aligned parallel to the pivot axis (HS), and

   - a bottom (6) whose bottom areas assigned to the mould cavity (10) shape the bottom end of the cast part,
   and using

   - a tundish (15) which on its pouring-in side for pouring the molten metal into the tundish (15) and on a pouring-out side abutting on the pouring-in side and on a bottom of the tundish (15) is at least in sections open in each case, via which the molten metal filled into the tundish (15) in casting operation flows out of the tundish (15) into the casting mould (5),

   wherein:

   - the tundish (15) is arranged on the casting mould (5) in such a way that its pouring-out side (16) butts against the lid (9) of the casting mould (5) and the bottom (18) of the tundish (15) is assigned to the reference side wall (7), wherein the pouring-in opening (13) of the casting mould (5) and the open section of the pouring-out side (16) at least overlap one another,

   characterised by the following production steps:

   - pivoting the casting mould (5) into a pouring-in position, in which the main plane (HE) of the reference side wall (7) encloses an angle β1 that is less than 180° with the bath level (BS) of a molten metal portion (S) to be filled into the tundish (15) and the bath level (BS) of the molten metal portion (S) to be filled into the tundish (15) is located below the filling opening (13) of the casting mould (5);

   - filling the tundish (15), which is in the pouring-in position, with the molten metal portion (S) which is sufficient for filling the casting mould (5);
   and

   - pivoting the casting mould (5) with the tundish (15) arranged on it about the pivot axis (HS) into a pivot direction, in which as a result of the pivoting molten metal (S) flows out of the tundish (15) into the casting mould (5), wherein the pivoting is continued until an end position is reached, in which the casting mould (5) is filled with molten metal (S), and wherein the angle β1 enclosed in each case between the main plane (HE) of the reference side wall (7) and the bath level (BS) of the molten metal portion (S), which is contained in the tundish (15) in each case, is at least constantly less than 180° until the melt flowing into the casting mould (5) hits the bottom (6) of the casting mould (5).
2. Method according to Claim 1, characterised in that the bottom (18) of the tundish (15) is flat on its side facing the molten metal (S).
3. Method according to any one of the preceding claims, characterised in that a bottom area formed on the inside of the tundish (15) encloses a right angle with the bottom (6) of the casting mould (5).
4. Method according to any one of the preceding claims, characterised in that the pouring-out side (16) of the tundish (15) assigned to the casting mould (5) is open.
5. Method according to any one of the preceding claims, characterised in that the filling opening (13) of the casting mould (5) extends over the side of the lid (9) of the casting mould (5) assigned to the tundish (15).
6. Method according to any one of the preceding claims, characterised in that a recess (12) is formed into the lid (9) of the casting mould (5), which when the casting mould (5) is completely pivoted takes up a melt volume which serves as a feeder (SV).
7. Method according to any one of the preceding claims, characterised in that an inflow surface (23) is formed on the side of one of the closed walls (21) of the tundish (15) facing the molten metal (S), this inflow surface (23) being inclined starting from the bottom (18) in the direction of the upper free edge of this wall (21) and at which the molten metal is directed when the molten metal is poured into the tundish (15).
8. Method according to any one of the preceding claims, characterised in that the angle β1 is 120 - 160° when the casting mould (5) is in the pouring-in position.
9. Method according to any one of the preceding claims, characterised in that two or more ingates (13) open out onto the lid (9) as pouring-in openings, via which the melt flows into the mould cavity (10) of the casting mould (5) when pivoting into the end position.
10. Method according to any one of the preceding claims, characterised in that the molten metal (S) when pivoting into the end position runs directly against the lid (9) of the casting mould (5) and flows into the respectively available pouring-in opening (13) there.
11. Method according to any one of the preceding claims, characterised in that the pivot angle covered by the casting mould (5) with the tundish (15) arranged on it between the pouring-in position and the end position is 110 - 160°.
12. Method according to any one of the preceding claims, characterised in that the pivot axis (HS) runs through or close to the bottom (6) of the casting mould (5).
13. Method according to any one of the preceding claims, characterised in that the molten metal (S) is a light metal melt.
14. Method according to any one of the preceding claims, characterised in that the cast part to be cast is a cylinder head or a crankcase for an internal combustion engine.

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