SG castings are also known by the name of ductile castings, nodular cast iron castings, and spheroidal graphite casting or SG castings in India. Foundries manufacturing and molding intricate casting shapes have to experience certain types of defects while executing production process in the absence of supervisors and proficient experts. If any of these castings has arrived at your door and you still can’t figure out why it’s not working, then here are some common defects to explain you different types of casting defects. With this information, you will be able to identify the defect type and can repair or fix it soon.
- Small narrow cavities appear on the casting surface while machining
This defect is called as dispersed shrinkage. It is usually caused in iron components when the carbon content is low or nitrogen content is high in the molten metal.
- Thin bits of metal at the parting line
This defect is called as flash projections. This is usually caused when the clearance between bottom and top of the metal casting mold halves is huge and allows metal enterance and solidification. This can be eliminated when the engineer start taking care in pattern, core and mold making.
- Cavities in the casting clumped together at one location
This defect is called as blowholes or pinholes. This is usually caused when gas is trapped in the molten metal during solidification process. It can be appeared in any region of the SG castings. Indian foundries have issued related guidelines for their engineers to eliminate this defect and produce seamless casting components.
- Folded shiny films in the walls appeared in your castings
This defect is called as lustrous carbon. These are wrinkled films outlined and found inside the iron casting walls and cause linear discontinuity in the structure. It is usually caused when materials or core additives and binders volatize, mold and become entrained in the molten metal.
- You see partial separation in one of the walls of your casting
This defect is called as cold shut. This is usually occurs when the wide casting surface has thin and difficult to fill sections.
These are most common defects you will experience while buying castings from the manufacturing foundries. Our aim was to inform you about such defects; we hope this article will help you in understanding all of the defects that are commonly found in a casting. If you are a casting maker, you can eliminate these defects and design your casting shapes flawlessly.
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