Gray iron and SG (ductile) iron castings
The company was founded by a metallurgist, and the iron we pour is a decision we make with you rather than a default. Which of the two your part needs comes down to how it is loaded.
Gray cast iron
Absorbs heat and vibration, wears evenly and machines easily, which makes it the usual choice for brake drums, lift pump covers and pump housings.
SG (ductile) iron
Spheroidal graphite gives far more strength and toughness than gray iron, so we use it where a part carries load or shock: rear axle tubes, wheel hubs, crankshafts and clutch drive plates.
Not sure iron is right?
If the part has to be light, fill very thin sections or resist corrosion, aluminium may suit it better; if it runs against a steel shaft, brass or bronze usually will. We pour all of them, so the recommendation is not a sales pitch. See our aluminium and brass pages, or just send the part and ask.
How we check a casting
Dimensional and visual checks are done here on every part. Laboratory work is not: we do not own a spectrometer or run a testing laboratory, so hardness and chemical analysis go to an outside laboratory when a drawing calls for them, and you get the report.
- Dimensional inspection with calipers, micrometers and height gauges
- Visual inspection for porosity, cracks and inclusions
- Fit check against your sample, where the part was reproduced from one
- Hardness or chemical analysis arranged with an outside laboratory on request
Questions customers ask
What is the difference between gray iron and SG iron?
The graphite shape. In gray iron it forms flakes, which damp vibration but crack under load. In SG iron it forms spheres, which makes the part far stronger and tougher. Load-bearing parts get SG iron; damping and wear parts are usually gray iron.
Can you match the material of a sample I send?
Yes. We identify the material family from the part and its use, then confirm the casting alloy with you before production.
Do you supply test results with the parts?
We carry out dimensional and visual checks in-house and can report them with your order. Hardness and chemical analysis need laboratory equipment we do not own, so we arrange those with an outside laboratory when your drawing calls for them. Tell us what your customer requires and we will price it in.
Tell us what you need made.
A drawing, a CAD file or a worn sample part is enough to start. We are in Korangi, Karachi, and we answer on WhatsApp.