Besides the presence of gas bubbles, and the result of segregation in a steel ingot, there are other defects which result from the pouring and cooling of the ingot in the mould.

A mass of molten metal naturally begins to cool at the surface, and as this chills, it forms a solid envelope about the molten mass in the interior. The contraction which results from cooling causes the metal to be drawn to the solid part as it cools, and in this way the central part of the ingot finally cools in a honey-combed state. The formation of the cavity at the center of the ingot is called piping. By the action of gravity on the molten metal this cavity is formed well toward the upper end of the ingot, and for this reason, the ingot is always cast on end. The piping should be cut off in the discard.

Surface cracks will appear if the ingot is taken hot from the mould and exposed to air sufficiently cold to make this surface contract enough to disrupt. These cracks may ruin steel otherwise good, because in rolling the ingot, cracks simply close up but do not weld together, and in this way the material is more or less weakened.

In pouring, globules of steel are apt to splash against the sides of the mould and become chilled into shot. These fall into the molten metal but may not be wholly re-melted, particularly if they rest against the sides of the mould. When the ingot solidifies these shot are more or less separate from the metal surrounding them. These defects are called cold-shuts.

Also in pouring, a film of metal from the ladle may strike on the inside of the mould and become chilled, sticking to the mould. This forms a lamination, as molten metal rising in the mould does not entirely re-melt it.