INDUCTION STIRRER/CONTINUOUS CASTING MOULD ASSEMBLY

Abstract: An induction stirrer/mould assembly for use on a continu­ ous casting machine, comprising: a coil assembly (2) having an outer frame (5) securely fastened to a vibrating table (1) of the casting machine and comprising induction stirring coils (4) mounted in the outer frame (5); and a continuous casting mould assembly (3) detachably mounted on said outer frame (5) of said coil assembly (2), the four sides of the mould assem­ bly (3) being provided by separable mould walls (9) each having a copper facing plate (10) securely joined to a reinforcing backing plate (11).

Description: This invention relates to an induction stirrer/mould assembly according to the precharacterising portion of claim 1. Such an induction stirrer/mould assembly is known in the prior art. The known induction stirrer/mould assemblies provide some problems with alignment of the mould assembly. Therefore there is a need to reduce these alignment problems. To solve this problem the subject matter of claim 1 is proposed. The dependent claims 2 to 5 relate to special embodiments of an induction stirrer assembly according to claim 1. The invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings which show by way of example some preferred embodiments of the invention. In the accompanying drawings: Figure 1 is a schematic plan view of an induction stirrer/mould assembly for a continuous moulding apparatus, embodying the present invention ; Figure 2 is a schematic side view of the induction stirrer/mould assembly of Figure 1 ; Figure 3 is a sectional view taken on line III-III of Figure 1 ; and Figure 4 is a sectional view taken on line IV-IV of Figure 3. Hereafter, the invention is described more particularly by way of a preferred embodiment shown in the drawings. The mould assembly according to the invention includes a coil assembly 2 mounted in a vibrating table 1 of a continuous casting machine, the vibrating table 1 being substantially in the form of a rectangular frame, and a mould assembly 3 received in a frame of the coil assembly 2. The coil assembly 2 which includes coils which act as electromagnetic inductors 4 for imparting rotary motion to the molten metal has a rectangular frame 5 of L-shape section, which is open on the inner side and receives therein the electromagnetic inductors 4 in such a way that the operating sides of the inductors 4 face inwards. The frame 5 is securely fixed to the vibrating table 1 by bolts 7 at mounting portions 6 which are formed in the upper part thereof. Further, cotter pins 15 are mounted on the frame for mounting the mould assembly 3, and the frame 5 is provided with a terminal box 8 for connection to a supply of power or cooling water which are to be fed to the electromagnetic inductors 4. In the particular embodiment shown, the mould assembly 3 is arranged to provide, for example, a mould for casting blooms. The respective mould walls 9 are each basically of the same construction and are assembled by bolts or other suitable fastening means to form longer and shorter sides of the mould and have dimensions corresponding to the dimensions of the bloom to be cast. The mould walls 9 each have a facing plate 10 of copper or copper alloy on the inner side which contacts the molten metal, and a backing plate 11 which is securely fixed to the copper facing plate 10 to provide the required strength of the mould. The backing plate 11 is formed of a non-magnetic metal like stainless steel, for example, in order to reduce the attenuation of the electromagnetic force of the inductor 4. For mounting the mould assembly 3 on the frame 5, the backing plates 11 on the longer sides are formed with brackets 14 which extend onto the frame 5 and are provided with holes for receiving the cotter pins 15. These holes are preferably elongated slots to permit relative movement of the mould assembly 3 and frame 5 when adjusting the alignment of the mould assembly 3 as will be described hereinafter. For cooling the molten metal, the backing plates 11 and copper facing plates 10 are provided with cooling water passage grooves 12 extending between upper and lower longitudinal water passages 26 which are formed in the upper and lower portions of the respective mould walls. The longitudinal water passages 26 are connected to intercommunicating passages 25 which are formed through the backing plates 11 at suitable intervals. The facing surfaces of the backing plates 11 and copper facing plates 10 are sealed together by an O-ring 13. A water jacket 22 made of a non-magnetic metallic material is formed on the rear side of each backing plate 11, the water jacket 22 being divided into two chambers by a partition wall 24 which is provided in an upper portion of the water jacket 22. One chamber of the water jacket 22 serves as a cooling water supply passage 27, while the other chamber serves as a cooling water discharge passage 28. These cooling water supply and discharge passages 27 and 28 communicate with a water box 29 which is formed in the backing plate 11. Although cooling water may be supplied to and discharged from the mould walls of the longer and shorter sides independently of each other, it is preferred to connect the cooling water supply and discharge passages of the longer sides to the shorter sides by means of connectors 30 so as to simplify the piping of the cooling system. The piping for supplying and discharging cooling water to and from the cooling system of the mould assembly 3 can be further simplified by providing cooling water supply and discharge boxes 31 and 32 on the frame 5 and vibrating table 1, respectively, as shown in Figure 4. Foot rolls 17 are mounted at the lower end of the mould assembly 5 though they are not necessarily required. However, it is recommended to provide such foot rolls 17 to support and prevent break-out of a newly cast strip which is still a thin shell immediately beneath the mould assembly. Provided between the mould assembly 3 and frame 5 is a mould aligning means for adjusting the position of the mould assembly 3 on the frame 5 relative to a cast strip guide consisting of, for example, a number of guide rollers which are located in a secondary cooling zone immediately beneath the mould assembly 3. Thus, as illustrated in Figure 3, the mould aligning means comprises reference blocks 18 fixed to the underside of the mould assembly 3 by welding or by bolts in at least two different positions. The blocks are mounted on one of the backing plates 11 at a position opposite the bottom wall of the frame 5 (the end face of the bottom wall of the frame 5 providing a reference plane for determining the alignment of the guide rollers), and shims 19 are attached to the reference blocks 18 by bolts. When mounting a mould assembly 3 on the frame 5, the surfaces of the mould walls 9 with new or reground copper plates 10 are firstly aligned with the foot rolls 17, and then the thickness of shims 19 is adjusted in such a manner as to hold a predetermined distance between the end faces of the shims 19 and mould wall 9. Thereafter, the mould assembly 3 is fitted into the outer frame 5, pressing the end faces of the shims 19 of the reference blocks 18 against the end face of the bottom wall of the outer frame 5, and fixing the mould assembly 3 to the outer frame 5 by the cotters 13. Although the reference blocks 18 are provided on the mould assembly 3 in the particular example shown, they may be attached to the bottom wall of the outer frame 5 if desired. However, it is advantageous to provide the reference blocks on the mould assembly 5 to adjust the mould alignment promptly in a simple manner. For replacing the copper plates 10 of the mould walls, fresh copper plates are attached to the backing plates 11 of the longer and shorter sides, along with the necessary seal means for the cooling water passages, and then the mould walls are reassembled to provide a mould assembly 3 having dimensions corresponding to the bloom to be cast. At this time, the thickness of the shims 19 on the reference blocks 18 at the lower end of the mould assembly 3 is adjusted so that the end faces of the shims 19 and the opposing surface of the mould wall are spaced from each other by a predetermined distance, and, in a case where the mould assembly is provided with the foot rolls 17, the mould wall surfaces are also aligned with the toot roll surfaces. This mould assembly 3 is then mounted on the coil assembly 2 on the vibrating frame 1, the cotter pins 15 on the coil assembly engaging in the elongated slots which are formed in the brackets of the mould assembly 3. The mould assembly 3 is moved until the reference blocks 18 at the lower end of the mould assembly 3 are abutted against the end face of the bottom wall of the frame 5. The mould assembly 3 is securely fixed to the coil assembly 2 by fitting cotters 16 in the cotter pins 15, with the reference blocks 18 held in intimate contact with the end face of the bottom wall of the frame 5. Upon mounting the mould assembly 3 on the coil assembly 2, the mould is automatically aligned with the cast strip guide means which is located beneath the mould, simultaneously connecting its cooling water supply and discharge passages with the corresponding ones on the part of the coil assembly 2. As is clear from the foregoing description, the described induction stirrer/continuous casting mould assembly has a number of advantages as

Claims: 1. An induction stirrer/mould assembly for use on a continuous casting machine, comprising: a coil assembly (2) having an outer frame (5) securely attached to a vibrating table (1) of said casting machine and comprising induction stirring coils (4) in said outer frame (5) : a four sided continuous casting mould assembly (3) mounted on said outer frame (5) of said coil assembly (2) comprising separable mould walls (9) each comprising facing plates (10), each of which is securely joined to and reinforced across its back surface by a reinforcing backing plate (11), each facing plate (10) and its respective reinforcing backing plate (11) forming therebetween cooling water passage grooves (12) for cooling the rear surface of the facing plate (10), the mould assembly (3) being detachably mounted on said outer frame (5); a cast strip guide means located in a secondary cooling zone immediately beneath said mould assembly (3), characterised by; the end face of the bottom wall of the frame (5) providing a reference plane for determining the alignment of the guide means: mould aligning means (19), (18) for adjusting the position of said mould assembly (3) with respect to said frame (5) which comprise; at least two reference blocks (18) adjustably fixed at a lower end of said mould walls (9), said reference blocks being abuttingly engagable with an end face of a bottom wall of said outer frame (5) of said coil assembly (2); and a shim (19) attached to at least one of said reference blocks (18) for providing a predetermined distance between the end face of the shim (19) and the mould wall (9), whereby the mould assembly is then fitted into the outer frame (5) so that the mould assembly (3) is positioned in alignment with the guide means. 2. The induction stirrer/mould assembly as claimed in claim 1 characterised in that the mould walls (9) on the longer sides of said mould are provided with brackets (14) at the upper ends thereof, said brackets (14) being detachably attached to said outer frame (5) of said assembly (2). 3. The induction stirrer/mould assembly as claimed in claim 1 or 2, characterised in that each one of said mould walls (9) is provided with cooling water passage grooves (12) between the facing surfaces of said facing plate (10) and backing plate (11), which grooves (12) extend between longitudinal water supply and discharge passages (26) formed in upper and lower portions of said mould wall (9), and a water jacket (22) is formed in the rear side of said backing plate (11) communicating with said cooling water supply and discharge passages (26) through intercommunicating passages (25) formed thorugh said backing plates (11). 4. The induction stirrer/mould assembly as claimed in claim 3, characterised in that said water jacket (22) is divided into two chambers (27, 28) to form a cooling water supply passage (27) and a cooling water discharge passage (28) and connectable to cooling water supply and discharge passages on the part of said coil assembly (2) upon fitting said mould assembly (3) in said outer frame (5) of said coil assembly (2). 5. The induction stirrer/mould assembly as claimed in any of claims 1 to 4, characterised in that foot rollers (17) are mounted below said mould assembly (3).

Inventors: OKAMOTO, HIROSHI
Applicants: KABUSHIKI KAISHA KOBE SEIKO SHO
Application year: 1985
Main classification: B22D11
IPC codes: B22D11