(1) Ductile iron castings have large overall dimensions, high requirements for size and wall thickness control, large wall thickness difference, complex structure and easy to produce shrinkage defects. On the one hand, a reasonable parting and core separation scheme is needed to achieve accurate control of the size and wall thickness of ductile iron castings; On the other hand, it is necessary to realize effective feeding of molten iron through reasonable feeding system design to meet the high compactness requirements of ductile iron castings.
(2) It is required to use fluorescent magnetic powder for 100% area MT inspection, which puts forward high requirements for the control of scum on the surface of ductile iron castings: on the one hand, it is necessary to improve the purity of molten iron and reduce magnesium residue; On the other hand, the gating system needs to have good slag retaining capacity to achieve smooth mold filling, and it needs to effectively control the generation of slag to meet the high appearance quality requirements.