GB1179739A - Improvements in or relating to Hot Tops or Feeder Heads for Ingot Moulds - Google Patents

Abstract

1,179,739. Ingot moulds; introducing molten metal. VALLAK (G.B.) Ltd. 4 June, 1968 [2 June, 1967], No. 25564/67. Heading B3F. A hot top 5 for an ingot mould 1 comprises a lining 6 fixed within the upper inner end of the mould and a central unit 12. The lining 6 extends flush with the inner surface 2 of the mould. The central unit 12, which may be premoulded, moulded in situ, or constructed of tiles, converges upwardly from a shape closely corresponding to the cross-section of the mould and is preferably a sliding fit within the mould. Tiles 9 may be wedged into the recess in the mould wall or fixed by studs to the mould wall to form the lining 6. Ledges 16 are provided in the lining 6 to support the central unit 12. Alternatively, a frame 18 may be attached to the central unit. The hinged arms 21 of the frame fit over lugs 4 of the ingot mould and the frame not only supports the central unit but prevents it from rising on the surface of the melt during pouring. Weights or straps can also be used to stop the central unit from rising. When bottom pouring the melt, molten metal must not escape by the gap between the central unit 12 and the lining 6, so pouring is halted when the level of the melt in the mould reaches the lower edge of the central unit and the metal is allowed to solidify in the gap; pouring being then recommenced. To aid solidification of the melt in the gap a metal strip may be provided around the base of the central unit to act as a chill, or a granular substance that frits under the heat of the molten metal may be included above the gap.