WO2013010663A1 - Mould for continuously casting long metallic products - Google Patents

Abstract

A mould for continuously casting long metallic products is provided with a round or polygonal cross section. The mould (10) is manufactured from a multiplicity of sheet-metal elements (11, 12, 13), which are layered one on top of another, over the entire height thereof. The sheet-metal elements (11, 12, 13) as parts are joined together tightly without gaps by a joining technique, preferably by friction stir welding and/or by a soldering process. With this formation of the mould, it is possible for the closed cooling ducts to be easily integrated in the mould, and the mould can nevertheless be formed with thin walls.

Description

 Mold for continuous casting of long metallic products

The invention relates to a mold for the continuous casting of long metal products with a round or polygonal cross section, which is at least partially made of a one-piece tube or of several pieces.

Conventional molds for continuous casting of long metal products, such as billets, billets, round, double T-Vorprofile or the like

CONFIRMATION COPY are made either from a one-piece, round or polygonal tube or from assembled panel elements.

Is also known molds, which are made of a solid block and near the Kokillenhohlraumes have cooling holes.

These one-piece, mostly made of copper molds are known to produce consuming, but offer casting advantages, since they are gap-free and dense. Such molds must be produced in several operations by first cast, then with appropriate thorns first warm and then cold formed and pulled or pressed. Due to these many complex operations and the required high-performance forming units and order-specific tools, which are required for a sufficiently accurate production, long delivery times arise when a mold for a particular casting format is ordered.

In a mold for continuous casting of blooms, slabs or billets according to the document EP-A 2 014 393 a one-piece mold tube is provided, which is surrounded in each case by a support casing or support plates. Between the mold tube and the support casing or the support plates limited cooling channels for guiding cooling water are arranged by support profiles and / or connection profiles. However, the production of such with a high life and best cooling effect distinctive Kokillenrohres is associated with relatively much and accurate processing and the delivery time is long, since the one-piece base pipe must first be prepared by conventional means. Are also known Kokillenrohre with closed cooling channels in the form of round deep holes, which emanate from one or both faces of the mold tube. Such cooling holes are expensive to manufacture, and since they can only be rectilinear, their precise and cool optimal placement with respect to the mold cavity is difficult.

The present invention was the object of the present invention to provide a mold according to the type described above, by means of which the production of the same simplified and, accordingly, the entire manufacturing process in a shorter period of time is possible.

Furthermore, cooling channels in the mold in different, cooling technically optimal versions with respect to cooling channel cross-sections and arrangements with respect to the inner surface of the Kokillenhohlraumes can be provided without this being associated with a significant increase in manufacturing costs. Furthermore, it should be possible to place the water inlet and outlet not only separately at both pipe ends but together at one of the pipe ends.

The object is achieved according to the features of claim 1.

According to the invention, a plurality of stacked sheet metal elements are provided as joined sections either over the entire or at least over a certain height of the mold. hen, wherein the remaining part of the mold is formed from a one-piece pipe section, one or more flanges or other assembled sections, wherein the sections preferably by stirring friction welding and / or electron beam welding, soldering, electrodeposition and / or similar methods are inseparable zusammenfügbar , The sections mentioned may have cutouts, channels or holes for cooling water flow. The aforementioned plate-shaped sections can preferably be produced on a numerically controlled water-jet cutting system.

Alternatively, in the context of the invention, the mold may be formed from joined pieces extending in its longitudinal direction, preferably in the form of cut-to-length and, if necessary, bent extruded solid or hollow profiles. These sections can also be attached to the outside of a one-piece round or polygonal mold and jointly designed such that between these cooling channels for the guidance of water cooling are formed, the sections again by stirring friction welding and / or by a soldering and / or similar are joined together.

With this inventive design of the mold, the closed cooling channels can be integrated in a simple manner in the mold and they can still be formed thin-walled. The cooling channels can, depending on the mold area in cooling technically optimal distance to the inner mold surface, which favors the solidification conditions and extends the life of the mold. Depending on the mold area, the individual sections can, if required, be made of different types of copper or else of other materials, such as stainless steel, in order to reduce the production costs or to improve the service properties.

For example, the individual height regions of the mold can be produced in accordance with the thermal load during the casting process from layers with different levels of thermal conductivity in order to achieve better thermal stability of the mold body. The individual stacking plates can also be made of different materials, e.g. Copper materials in the heat-conducting inner area and the outer edges of stainless austenitic steel to improve the magnetic permeability. In order to reduce the eddy current losses when using magnetic fields, the stacking plates can be provided with a thin electrically insulating layer.

These sections can be assembled very precisely and very efficiently by means of a suitable joining technique, preferably stirring-friction welding and / or by a soldering method and / or the like. The mold cavity can be machined, preferably processed by longitudinal planing or milling. Subsequently, suitable coatings can be applied to the inner surface, such as hard chrome and / or nickel. Also conceivable are coatings, for example copper or nickel, which are preferably applied galvanically before mechanical processing. Another advantage is that it is possible to resort to a stock material produced by the copper manufacturer in stock in the form of rolled plates or extruded hollow or pre-profiles.

Embodiments and other advantages of the invention are explained in more detail with reference to the drawing. Show it:

1 is a perspective schematic representation of a mold according to the invention with stacked sheet-metal elements;

 Fig. 2 is a plan view of a single sheet metal element for a mold;

 3 shows a perspective schematic view of an alternative mold according to the invention with elongate sections of extruded hollow profiles and end flanges made of plate material arranged lengthways next to each other;

 Fig. 4 shows a cross section of a thin-walled, one-piece smooth

 Mold with at its outer periphery attached profiled sheet metal elements or mold profiles for the formation of cooling channels, wherein the part shown on the left of the mold has larger corner radii or other variants of sheet metal elements as shown on the right;

5 shows a cross section of a thin-walled, one-part mold, which are shown in four different variants each one quadrant of the cross-section illustrative; 6 is a longitudinal section through an inventive mold with stacked sheet metal elements, in which in the left half above and below each a flange, while in the right half only above a flange is illustrated;

7 shows a cross section through the mold of Figure 6 at the height of the connecting flanges ..; and

 Fig. 8 is a section of another variant of a mold partially shown with an upper flange.

Fig. 1 shows a mold 10 for a mold assembly, which has in conventional manner a mold cavity 15 having an approximately square cross-section and is provided for the production of billets. However, the mold 10 could also be designed differently in cross-section, for example as a mold tube for a billet with a rectangular, octagonal, trapezoidal, double-T-shaped or round shaped hollow cross-section. This mold 10 is also bent in the direction of the plane formed by the strand course in a known manner, which is therefore not explained in detail. At least the outer circumference could also be straight in the longitudinal direction.

According to the invention, this mold 10 consists of over their entire height stacked sheet metal elements 1 1, 12, 13 as joined sections, the respective adjacent sheet metal elements are joined together by a joining technique, very advantageous by stirring friction welding, and / or by a soldering and / or the like , The sheet metal elements are welded in each case over their entire, with the adjacent sheet metal element in contact annular surface. The other sheet metal elements 1 1, 12 are each shaped, for example, punched or cut by means of water jet that they have transverse to their longitudinal openings 16 which form cooling channels 17 in the assembled state of the mold for the cooling thereof. The arrangement and the number of openings 16 are optimally adapted to the casting parameters, wherein such openings 16 are advantageously arranged distributed on all four sides of the mold. At the upper and at the lower end of the mold 10 inlets and outlets 18 of the cooling channels are provided, which are formed by corresponding recesses in the sheet metal elements 12.

These stacked sheet metal elements 1 1, 12, 13 have an approximately identical shape, wherein at least the two located at the top and bottom end sheet metal elements 13 form a conclusion and therefore contain no openings 16.

Advantageously, the mold cavity 15 forming inner surfaces 15 'after the welding together of the sheet metal elements 1 1, 12, 13 machined by milling or planing, so that these inner surfaces 15' can be provided with sufficient accuracy. These inner surfaces can be coated galvanically or by other methods before and / or after the machining.

FIG. 2 illustrates a variant of a sheet-metal element 21 as a section of a mold which, in contrast to that of FIG. 1, has rounded corners. The sheet metal elements have openings 16 on the entire circumference, which form water-bearing channels after stacking of the elements. By providing sheet metal elements 1 1, 21 there is the further advantage that such openings can be made in a simple manner practically in any shape and arrangement.

In contrast to the mold 10 according to FIG. 1, according to the invention, at the upper or lower end of the mold 30, end flanges made from plate material or from a plurality of stacked sheet-metal elements 31 are provided. Between these flanges, a plurality of longitudinally extending portions 32, 33, 34, 36 are preferably used and extruded from extruded hollow sections.

There are four elongated, the corners of the mold forming sections 32, 34 and four elongated sections 33, 36 are provided, which are each arranged in the central region of the mold. Furthermore, cooling ducts 37 are contained in these sections 32, 33, 34, 36, for the purpose of which these sections are designed in each case as square-shaped, shaped profiles. In addition, inlets and outlets 38 are provided for the cooling liquid at the top and bottom.

It is also possible to provide these inlets and outlets on one of the two mold ends, preferably on the upper part. In this case, the cooling water flow at one of the ends is reversed and directed either via cooling channels or separate, underlying return channels to outlet channels at the other end. The adjacent sections and the sheet metal or plate elements are according to the invention by stirring friction welding and / or connected by a soldering process tightly, such that the sections 32, 33, 34, 36 welded over its entire length or sheet metal elements 31 around and / or soldered.

In a mold 40 according to FIG. 4, larger corner radii or other variants of sheet metal elements are shown in the part shown on the left than shown on the right. This mold 40 is characterized in that it is composed of a one-piece, thin-walled inner tube 41 and from this surrounding sections. These sections are shaped as wave-shaped sheet-metal elements 42 and joined together with their webs 43 extending along the mold 40 by stirring friction welding or the like with the mold, whereby cooling channels 44 are formed on the cross-sectional circumference, each with an inlet and outlet not shown in detail are provided.

Furthermore, a metal jacket 46 surrounding the mold 40 in the half shown on the left is indicated, which in turn is attached to the sheet metal elements 42 via friction friction welding. In this case, additional cooling channels are formed and the rigidity of the thin-walled mold is thereby increased. Since the requirements for the cooling of the corner areas are different depending on the size of the corner rounding.

In a thin-walled one-piece mold 60 according to FIG. 5, four quadrants with different design variants with and without a metal jacket or in the left half are large and in the right half small corner radii 61, 62 indicated. On the outer periphery of the mold 60 incorporated cooling channels 65 are provided, which are closed by illustrated in different variants flat or curved sheet metal elements 66, 67 or hollow profile sections 68 and so supply or return channels 65 '65 "form.

FIGS. 6 and 7 show a further embodiment of a mold 50 according to the invention, which, similar to the one according to FIG. 1, is assembled from sheet-metal elements 51 stacked on top of one another and provided with openings 56 for the cooling channels. In this mold 50 is in the left half at its upper and lower end depending a flange 53, 54 arranged as a conclusion, which radial openings 53 ', 54' are assigned, with which the cooling liquid, for example, at the lower flange 54 and at upper flange 53 is again led away. Thus, the mold 50 can be easily and quickly connected to the cooling water inlet and outlet. The connection openings of the flanges can also be arranged vertically or horizontally and the connection can be made in the case corresponding to a horizontal or vertical Wasserleitplatte. The flanges 53, 54 are preferably produced in several parts and, in turn, joined together in the context of the invention, in particular by stirring friction welding, with the sheet metal elements 51.

In the right-hand half of Fig. 6, as an alternative, only a flange 58 is shown at the top, in which the cooling-water inlet or outlet 58 ', 58 "are assigned. The envisaged cooling channel 59 is deflected upward again on the underside of the mold then leads to the sequence 58 ". The- This flange 58 could for example also be arranged on the underside or in the middle of the mold.

As shown in Figure 7, individual areas of Kokillenkühlung, in the case of corner surface areas, but also, for example, curved and straight Kokillenseiten be sewn separately with cooling water and controlled cooling. It is also possible to guide the cooling channels so that at the pipe end, a reversal of the flow direction takes place. In this case, the inflows and outflows of the cooling water can be integrated into the flange at the upper mold end.

FIG. 8 shows a further variant of a partially illustrated mold 80 with an upper flange 81, which according to the invention is attached to the pipe. In addition, cooling channels 83 and inlets or outlets 84 are again provided. The mold 80 may be made in one or more parts, as provided for example in Fig. 3.

The invention is sufficiently demonstrated with the embodiments explained above. Of course, it could also be clarified by other variants. Thus, for example, the layered sheet-metal elements could be provided with a thicker wall thickness and the openings serving as cooling channels could be guided horizontally in these partially or all around. As a variant, the mold according to FIG. 4 or 5 could also be joined together, instead of in one piece, of sheet metal elements stacked on top of one another and / or of elongate sections.

Adhesive bonding or adhesive bonding could, in principle, also be used as the joining technique, for example with a high-tempering dimensionally stable epoxy or silicone adhesive, a two-component adhesive, wherein the thermal conductivity of the adhesive may be increased with metal additives.

It is likewise conceivable to build up the mold in layers by means of a beam melting process, such as, for example, SLM selective laser melting or DMLS direct metal laser sintering, starting from the metal powder, or to connect this with sections.

Claims

1. mold for continuous casting of long metal products with a round or polygonal cross section, which is at least partially made of a one-piece tube or of several pieces, characterized in that as joined sections, a plurality of stacked sheet metal elements (11, 12, 13, 21, 31, 51) are provided either over the entire or at least a certain height of the mold (10, 30, 50), the remaining part of the Mold (30, 50) is optionally formed from a one-piece tube or from joined pieces (32, 33, 34, 36), or that pieces (42) are attached to the outer side te a mold (41) and thereby cooling channels (44 form) for the leadership of the water cooling, the sections are by a joining technique, preferably by stirring friction welding and / or by a soldering method gapless tightly joined together. 2. mold according to claim 1, characterized in that the aufei- nernergeschichteten sheet metal elements (1 1, 12, 31, 51) each have openings (16, 56) through which the cooling channels for the guidance of the water cooling are formed. 3. Mold according to claim 2, characterized in that the sheet metal elements (1 1, 12, 31, 51) each have a plurality of circumferentially distributed openings (16, 56). 4. mold according to claim 2 or 3, characterized in that at the upper and / or at the lower end of the mold (10, 30, 50) inputs and outlets (18, 38) of the cooling channels (37) are provided. 5. Mold according to one of the preceding claims 1 to 4, characterized in that at least the uppermost and the lowest sheet metal element (13) are formed as a conclusion without openings (16). 6. Mold according to one of the preceding claims 1 to 5, characterized in that in the longitudinal direction of the mold (30) extending portions (32, 33, 34, 36) are joined together. 7. mold according to claim 6, characterized in that the sections (32, 33, 34, 36) as shaped profiles, preferably hollow profiles, are formed and cooling channels (37, 38) contain or form after joining. 8. mold according to claim 1, characterized in that the sections (42) on the outside of a mold (41) wave-shaped and are joined together with their projecting webs (43) with the mold. 9. Mold according to claim 1, characterized in that at the upper or lower end of the mold (50) depending on a flange (53, 54) is arranged as a conclusion, wherein the flanges radial openings (53 ', 54' ) are assigned, with which the cooling liquid is introduced at one flange, passed through the mold and the other flange. 10. mold according to claim 1, characterized in that the mold (50) is associated with a flange (58), said flange (58) has openings (58 ', 58 "), with which the cooling liquid introduced at the flange through which Chill through and deflected end and back to the flange (58) is guided. 1 1. Mold according to claim 1, characterized in that the mold cavity (15) forming inner surfaces (15 ') after the stirring friction welding of the sheet metal elements (11, 12, 13) are machined, preferably machined by milling or planing, so this Inner surfaces (15 ') can be produced with sufficient accuracy 12. mold according to claim 1, characterized in that on the outer periphery of the mold (60) incorporated cooling channels (65) and these closing flat or curved sheet metal elements (66, 67) or Hohlprofilab sections (68) to form Zu- or Return channels (65 '65 ") are provided.