What are the procedures to be followed by the ductile iron castings manufacturers?

By vr foundries on 5-June-2019

To deploy the perspective of ductile iron casting completely, manufacturers of ductile iron castings should follow the below procedures available for Ductile Iron, and how to respond to this procedure:

Heating treatments:
When ductile iron is subjected to heat treatment, its ductility is increased to even higher scale. Ductile iron treated with heat can improve the below factors: increase ductility, corrosion resistance, strength and toughness; wear resistance; enhance the consistency of properties and reduce internal pressure. 

Hardening treatments:
Hardening treatment is carried out by the castings manufacturers to enhance the abrasive resistance and surface hardening of ductile iron. This is a key trait of any ductile casting that is required to be quenched-hardened as it ascertains the depth of the casting, either fully or partially, to which it can be produced, as well as the harshness of quench needed to harden castings of various section sizes.

Difference in designs:
As ductile iron is not free from shrinkage, the foundry requires to sustain higher amount of metal into the shrinking zone. The foundry needs to design a part whose proportions increase consistently towards a location where feed metal is supplied through a riser sleeve. 

There is uneven cooling by aligning cross members resulting in weakness, distortion and hot spots. The recommended practice here is staggering cross member intersection.

Hot spots are created when ribbings are retained on either side of castings. Ribs must be about 80 percent as thick as the section they are attached, as this allows the solidification of the rib before the casting section. The rib’s shape should help in consistent cooling.