Three Important Points on Grey Iron Castings – Part 1

By vr foundries on 17-February-2020

There are three important features of designing with Grey Iron castings. Often what comes as an after-thought is the use of Shrinkage while designing. In comparison with Steel or Ductile Iron for castings, Cast Iron or Cast Iron can be easier and simpler to work with. This is due to reduced solidification shrinkage rate compared to DI or Steel. Since Grey Iron does not need as much heat to reach melting point, therefore it is simple to work with and exhibits increased fluidity in the mould.

Sparing a few exceptions including unusual wall thickness or very large castings, there is not much focus on the problem of feeding metal to heavier sections. So this means the low shrinkage profile results in castings not affected by hot tears as seen in other foundry metals including Steel or Ductile Iron. This enables increased freedom to the design of complexity and size/thickness of features compared to other foundry metals.

Do you face stress issues with Grey Iron castings? This is what inexperienced castings manufacturers go through when designing sand castings. Usually, a casting will come out of fabrication where the designer has been overly influenced by the quality of flat plates and other wrought shapes. The usage of these shapes and surfaces will be indicated by a lack of long radius fillets, tapered sections and sections of variable sections that are readily available in castings. There is no clean design, the casting is an assortment of small radii, bosses, ribs and plates resulting in poor castings that could crack when subject to stress.