Abstract: The disclosure relates to apparatus for applying a hot top lining in an ingot mould or ingot mould head box. The apparatus comprises a pair of slab support members each having two faces adapted to support an L-shaped slab of hot top lining material such that the L-shaped slabs are supported outside the members in the form of a rectangle, means for moving the members towards one another and apart to decrease or increase the size of the rectangle, supports for corner wedges located above the gap between supported L-shaped slabs when the members are in their most separated position, means for releasing corner wedges from such supports, and means for applying pressure to the tops of the corner wedges to urge them into the gaps between the L-shaped slabs.