DE3424457A1 - DEVICE FOR CONTINUOUS METAL CASTING - Google Patents

Abstract

1. Device for continuous casting of metals with a continuous casting mould more particularly coolable by cooling medium and with a thermally insulating head (hot top), wherein separating media can be fed into the region of the inner wall, laterally bounding the poured stream, of the mould or of the insulating head, and a separating medium supply channel at the boundary faces between two parts of the device which are disposed in axial alignment with one another in the region of the inner wall, more particularly between the mould and the insulating head, opens at the inner wall, characterised in that the separating medium supply channel (18) is provided with an insert (7) which is of granular form on at least one surface (7a).

Description

O / O / / rr Π Hans-Jürgen Müller

O 4 Z 4 4 O / .Lf-- Gerhard D. Schupfher

Te, e, on: (O 89.4 70 60 55/56

Telex: 523016 P.O. Box so 13 69

Telegram / cable: Lucile-Grahn-Straße 38 European Patent Attorneys

Zetapatent® Munich D-8000 Munich 80 mandataires en brevets europeens

HJM / Sa

Kaiser Aluminum Europe Inc. Cecilienallee 6-9
4000 Düsseldorf 30

Device for continuous casting of metals

Q / O / / C 7 CT Hans-Jürgen Müller

OM-ZMM-O / -Ο- Gerhard D. Schuofn

Gerhard D. Schupfner

Τβ, β, οη: (089) 470β0 _55/5 β

Telex: 5 23016 P.O. Box 8013 69

Telegram / cable: Lucile-Grahn-Straße 38 European Patent Attorneys

Zetapatent® Munich D-8OOO Munich 80 mandataires en brevets europeens

description

The invention relates to an apparatus for the continuous casting of Metals with a continuous casting mold that can be cooled in particular by coolant and with a thermally insulating insulating attachment.

Such a device is already known (US Pat. No. 4,057,100). the Use of an insulating attachment has the advantage that an axially shorter mold can be used, which in addition to saving space quality improvements of the cast strand also result. Compared to conventional casting technology without a hot head, there are also procedural aspects Benefits can be exploited.

In the case of such continuous casting devices, it is the one that cools the mold Coolant is often also used to be directed against the outer jacket of the cast strand in order to provide for accelerated cooling of the same. In addition, it is also known to use one or more feed channels to provide separating means between the cast strand and the inner wall of the mold or the insulating attachment, whereby a fluid separation between the cast strand and the inner wall takes place. In particular in the case of release agents which are also used as lubricants, this results in an even better continuous casting or ingot surface quality achieved. It has been shown, however, that the release agent is very within very narrow limits is to be supplied in a metered manner. For this purpose, on the one hand, it is already known, the interior of the mold through which the cast strand or the ingot passes, to connect with a separating agent storage chamber by wick-like cloths, which the separating agent from the storage chamber to the inner wall and therefore forward to the outer surface of the cast strand.

However, it has been shown that this wicking effect in the range of hot Inner wall leaves something to be desired after a short time, so that the wipes used as wicks have to be changed frequently. Also another known measure, according to which pronounced channels in the form of Gaps, grooves or machining grooves between each other axially abutting device parts are formed, requires special metering devices in the form of additional pumps or due to the inherent pumping action of the rising and falling melt level. before Problems arise especially when changing from one system to another.

The invention is based on the object of the device with simple To improve means in such a way that a simple and optimal dosage of the supply of release agents according to the respective application purpose he follows. In addition, it is desirable to convert existing continuous casting molds into such a hot head mold in a simple manner, which is provided with a thermally insulating insulation attachment.

The invention consists in that the release agent supply channel or Separating agent feed channels are formed in that the unevenness and depressions of a granular form on at least one surface Insert to feed the release agent to the effective point. For this purpose, it is advisable to use a sandpaper or sandpaper as an insert or emery paper that is resistant to release agents, i.e. in which the grains do not move from their base when release agents are added be replaced. This insert can, for example in the manner of a washer, simply axially between two abutting parts of the Device can be inserted. The one through the "labyrinth" of bumps Feed channels formed between an interface of such a device part and the insert conduct the separating agent, in particular beneath it Gravity at the decisive point between the inner wall and the cast strand. By choosing different grain sizes, it is possible to to change the dosage, for example, an insert with a large grain size

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to be replaced by another insert with a smaller grain size. With others In other words, the dosage is primarily based on the grain size of the granular insert.

A very fine micro-grain is recommended for low release agent requirements of grain 1000 (18ium) and a grain size for larger release agent requirements of, for example, grain 180 (75 / jm), while often sandpaper a grain size of 320 (46 µm) allows good optimization. When using this measure, the consumption of release agents is per cast Rope of 200 mm 0 and 7,500 mm in length when using rapeseed oil only 2 gr great.

It is advisable to cover the insert on one side with a release agent Glue to provide. It is useful to have this adhesive-coated back of the insert face upwards, while the granular one The surface in the installation position points downwards so that the release agent runs through the "labyrinth" on the underside.

According to another embodiment of the invention are in particular ceramic Isolating rings stacked axially one behind the other to form the insulating insert. The insulating rings are radially within a substantially tubular transducer held. As a result, the insulating rings are prevented from expanding radially during operation substantially, whereby the risk of cracks can be counteracted without this resulting in significant additional costs. On the contrary: the longer service life of the Insulating insert reduces the total costs not insignificantly «In addition This also enables insulating rings to be changed quickly.

If the release agent is supplied on the outside of the transducer, the transducer also protects the thermally insulating insulating rings from being "impregnated" with separating agents, so that the cracks develop even further and unnecessary release agent consumption is avoided.

If, according to a further embodiment of the invention, below the hot head If a graphite insert is arranged, the friction between the mold wall surface and the solidifying metal reduced; about that In addition, the indirect cooling is also reduced in that area, which results in an even better surface quality of the cast strand affects.

An exemplary embodiment of the invention is shown below with reference to the drawing explained in more detail. Show in it:

FIG. 1 shows, in partial cross section, a structure of a device according to the invention;

FIG. 2 shows the sub-area circled in FIG. 1 on an enlarged scale.

According to Figure 1, the device is designed for casting round bars. The cast strand, not shown, slides along the inner jacket surface la of the mold 1 before it comes into contact with the coolant KM, which emerges from the mold 1 through the coolant supply channel 16 from a coolant storage chamber 15. The coolant storage chamber 15 of the mold 1 is also limited by the device parts 12, 13 and 14; the annular device part 14 is with an opening 17 for Supply of coolant KM provided.

In this design, the mold 1 is above the inner jacket surface la turned out, namely for receiving a shrink-fit annular insert 2 made of graphite and for receiving the insulating attachment serving as a hot head or use. This insulating attachment is formed by the essentially tubular receiver 4, which has a collar 4a at the bottom has on which the lower of the four insulating rings 3 is supported. The insulating rings 3 are put together between this collar 4a and the clamping ring 9.

held with the help of a torque wrench in the axial direction on the insulating rings 3, which are made of ceramic material, is clamped. After turning off the clamping ring 9, the insulating rings 3 can be removed from the tubular receptacle 4 and exchanged. The outer circumferential surface 4b of the transducer 4 is located in the radial direction Distance from the inner surface Ib of the mold 1, so that an annular connecting line 10 results between the separating agent chamber 6 and that area which is between the lower part the connecting line 10 and the lower part of the lowermost insulating ring 3 or the upper part of the insert 2 made of graphite. In This area is the feed channel 18 - in reality consisting of an abundance of individual labyrinth-like channels - formed by the Bumps and depressions on the underside of the granular surface 7a of the insert 7 made of emery paper, which by means of the The adhesive located on the rear side 7b is also glued to the underside of the transducer 4 in the area of the collar 4a. The release agent, which in particular should also have lubricant properties, is filled into the separating agent chamber 6 via the opening 5, so that the gravitational force of the liquid column of the separating agent above the insert 7 doses the separating agent through the feed channel 18 radially drives inward. The insert 7 therefore serves at the same time as a kind of "distributor ring" for the uniform supply of separating agents to all lateral surfaces of the cast strand. About the leakage of release agent in the tilted state of the mold 1 from the release agent chamber 6, i.e. during the casting breaks To prevent the opening 5 is closed and prevents the sealing ring 8, in particular an O-ring, the passage of release agent from the gap between the sensor 4 and the mold 1.

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Claims (9)

Claims 1. Device for the continuous casting of metals with a particular Continuous casting mold that can be cooled by coolant and with a thermally insulating insulating attachment (hot head), with the release agent in the Area of the inner wall of the mold or of the insulating attachment laterally delimiting the cast strand can be fed, and a separating agent feed channel at the interfaces between two device parts arranged axially one behind the other in the region of the inner wall, in particular between the mold and the insulating attachment, opens out on the inner wall, characterized in that, that the release agent feed channel (18) is provided with or through an insert (7) which is granular on at least one surface (7a) the bumps and depressions of the granular surface (7a) is formed. 2. Device according to claim 1,
characterized in that the insert (7) consists of sandpaper, sandpaper or emery paper. 3. Device according to claim 1 or 2,
characterized in that the insert (7) is provided on the rear side (7b) facing away from the granular surface (7a) with an adhesive that is resistant to separation. 4. Device according to one of the preceding claims, characterized in that daG a sand bzvi /. Sandpaper with a micro-grain size between approx P 240 and etu / a P 1000 (in grain numbers according to DIN 69176 part 1). 5. Device according to one of the preceding claims, characterized in that that the insert (7) axially to / ischen the insulating insert and the mold (1) is arranged. 6. Apparatus according to claim 5,
characterized in that the mold (1) is provided with an insert (2) made of graphite and the insert (7) is arranged in relation to this insert (2) and the insulating insert. 7. Device for continuous casting of metals with a particular through Coolant coolable continuous casting mold and with a thermally insulating insulating attachment (hot head), in particular according to claim 5 or characterized in that the insulating rings (3) of the insulating insert from one substantially tubular sensor (4) are surrounded. 8. Apparatus according to claim 7,
characterized in that the tubular receiver (4) has a radially inwardly projecting collar (4a) at the lower end on which the insulating rings (3) are supported and which optionally serves to support the insert (7). 9. Apparatus according to claim 7 or 8,
characterized in that at least part of the outer jacket surface (4b) together with. at least a part of an inner, but opposite to the continuous casting serving strand-forming lateral surface (la) opposite the Cast strand set back shell surface (Ib) of the mold (1) a Connecting line (10) between the separating agent feed channel (18) and the separating agent chamber (6).