Improving Yield in Ductile Iron
Preet Inder Singh
4th Generation Foundryman | We specialize in manufacturing machined castings from Ductile iron , Grey iron & ADI; with over 18 years of export experience.
In the lock down when I was stumbling upon articles, I found this great read by Noberto T Rizzo Downes, Dana, Foundry Divison. There ten simple points to take care of to improve the yield in your ductile iron casting. ( you may google the article for details).
1) Use of Ceramic Foam Filters - Re-design your gating for shorter routes, reducing inclusion traps
2) Use of stable Raw Materials to give consistent results - like Carburisers.
3) Use of trapezoidal gate sections for minimum turbulent flow.
4) Optimizing pour time and pouring sequence
5) Optimum gating runner modulus to control temperature loss.
6) The use of risers to compensate expansion : The objective is to avoid over pressurization that generates expansion during the solidification producing the formation of secondary shrinkage. The application of this concept allow us to use small risers, improving the yield.
7) Placing risers at optimal locations.
8) Use of riser for more than one casting (whenever possible )
9) Use of top risers : The feeding is planned with relatively small size of risers.
10) Use of Hot Risers: Hot risers are very efficient and relatively small size is required.