Patent GB-1459494-A (GB)
Title: Continuous ingot casting machine
IPC: B22D11/14
Filed: 1974-01-28
Abstract: 1459494 Continuous casting; rolling URAL ORDENA TRUDO KRAS ZNAM POLITEKHNICHE INST IM SM KIROVA and NIZHNETAGIL ORDENA LENINA METALLURGICHE KOMBINAT IM VI LENINA 28 Jan 1974 03875/74 Headings B3F and B3M [Also in Division F1] Molten metal 55 from a vessel 1 is fed by a device 2 (incorporating an induction pump, or pneumatic feeder (see Division F1) wherein the metal may be heated) up into a curved mould 3 from the top of which the east strand 57 with solidified shell 56 is withdrawn by a dummy bar (4) and two curved metal side plates 5, Fig. 3, for which there are drives 16 for pressing them against the sides of the shell 56 (by way of rollers 18), the plates 5 being connected at one end to the bar (4), at the beginning of the withdrawal, and at the other end to the top of a curved descending section 19 of a beamsupported cooling, guiding and withdrawing arrangement, which section has a reversible drive 39 with a gear 21 on which it rests; a separate ascending section extends up to the section 19 and includes supporting rollers 8 mounted on a fixed structure and pairs of inductors 7 which, when activated, counteract the weight of the molten core and prevent backflow and which are mounted on beams 11, some swinging and some short and fixed. The inductors are clamped against the strand 57 for a stage of each withdrawal stroke of the intermittent extraction of the strand and have shoes which are cooled for protection and to cool the cast strand; the side plates 5 are also cooled for the latter purpose. The descending section 19 (where the strand is cooled by any well known secondary cooling arrangement) is swung down about a shaft 12 (which also supports, pivotally, the beams 11 supporting the lower inductors 7) by the gear 21, through an arc somewhat less than a mould length for withdrawal of the strand, borne on flanges 38, Fig. 8, of paired rollers 25 in the section 19 and gripped by the side plates 5 projecting from the descending section 19 into the ascending section, where they are guided by slots in the rollers 8. As indicated in Fig. 8, instead of a slab casting 57 as shown in Fig. 6, a number of smaller strands 57 may be produced, in a multicavitied mould. The pairs of rollers 25 are then in an offset arrangement as indicated. The rollers 25 rotate only when the section 19 is swung back up to its original position ready for another withdrawal swing. They are mounted in slideways and the spacing in the pairs is adjustable by blocks. Some of the rollers 25 have brake shoes (37) pushed against them and so are forced against the strand, during the withdrawal swing, to assist the extraction. In the case of a slab casting, e.g. of 400-2000 mm. width, each time the descending section 19 is swung back to its original position, discs 29, Fig. 6, on spring-mounted cooled spindles 27 at the top of the section, depress the faces of the strand 57 to prevent bulging at the bottom of the section, because the middle of the strand solidifies and connects the face walls. Before withdrawal of the strand(s) 57, the inductors 7 are drawn apart by hydraulic rams (14, Fig. 2, not shown) and the lower two pairs are raised by a further ram 13 away from the mould 3 for a distance equal to the expected shrinkage-back of the strand 57. After the initial withdrawal stroke, the dummy bar (4), which is connected to the descending curved section 19 and has a vent bore and may be coupled to the side plates 5 at three places, is detached from the plates and they are unclamped from the strand and lowered to their original position and then reclamped to the strand 57 by rams 16 and rollers 18, Fig. 3. Withdrawal is facilitated by dropping the pressure in the liquid core, backflow being prevented by the inductors 7. The next withdrawal relies on frictional grip of the plates 5 and inductors 7 initially, but when the latter reach the rollers 8 they are separated and the electromagnetic forces they induce in the strand shell aid the withdrawal. Rolling.-From the withdrawing arrangement the strand 57 passes to a roll mill stand 40 movably mounted on rollers 41 arranged in an arc so that rolling and withdrawal speeds need not be correlated. Shears 43 follow the stand.