Distinguish the three mainstream castings cast iron, cast steel and cast aluminum
Definition of castings
Castings are blank parts formed by pouring molten metal into mold and cooling it.
How to determine whether a part is a casting
It is determined based on the four major characteristics of castings, any one of them is present, casting should be given priority.
Three Main Categories of Casting Procurement
1. Cast Iron
It is divided into gray cast iron and ductile iron.
Gray cast iron:
·Common materials: HT150,HT200,HT250 / EN‑GJL‑150, EN‑GJL‑200, EN‑GJL‑250 (GJL means Lamellar Graphite Iron) / GG15, GG20, GG25 (GG means Grauguss in German)
·Features: Good shock absorption, noise reduction and vibration damping, low price, good casting performance, and is suitable for large and heavy parts
·Applications: Machine tool beds, bases, boxes, engines, pipes, pumps and valves, pulleys, etc.
Ductile cast iron:
·Common materials: QT400, QT450, QT500 / EN‑GJS‑350‑22, EN‑GJS‑400‑18,EN‑GJS‑450‑10, EN‑GJS‑500‑7(GJS means Spheroidal Graphite Iron) / GGG35, GGG40, GGG50 (GGG means Gusseisen mit Kugelgraphit in German)
·Features: High strength, good toughness, and impact resistance, it can replace some steel parts
·Applications: High-pressure valves, pump casings, flanges, crankshafts, gears, hubs, wind turbine hubs/bases, rail transit bogies, boxes, and structural parts of construction machinery, etc
2. Cast Aluminum
Cast aluminum is lighter than cast iron or cast steel, has good heat dissipation and corrosion-resistance, can be made into complex thin-walled parts, and is easy to form.
It is used for flowmeter/vortex converter housings, instrument casings, new energy vehicle motor/electronic control housings, battery trays, pneumatic/hydraulic valve bodies, connectors, communication equipment, and household appliance structural parts.
3. Cast Steel
There are many types of cast steel, such as carbon cast steel, alloy cast steel, stainless cast steel, heat-resistant cast steel, wear-resistant cast steel, etc.
Their comprehensive mechanical properties are stronger than those of cast aluminum and cast iron, and they are also resistant to tensile, compressive, impact, high temperature, high pressure and extreme working conditions.
Regular Purchasing List of Castings
| Material | Parts / Components |
| Cast Iron | Pump Housing / Pump Body |
| Valve Body | |
| Motor End Cover | |
| Gearbox Housing | |
| Machine Tool Bed | |
| Flywheel | |
| Pulley | |
| Brake Drum | |
| Exhaust Manifold | |
| Hydraulic Valve Block | |
| Cast Aluminum | Transmission Housing |
| Motor Housing | |
| LED Light Housing | |
| Heat Sink | |
| Instrument Housing | |
| Vortex Flowmeter Housing | |
| Pump Housing | |
| Valve Housing | |
| Drone Structural Parts | |
| EV Battery Housing | |
| Cast Steel | Cast Steel Valve Body |
| Pump Body | |
| Impeller | |
| Flange | |
| Mining Wear Parts | |
| Crusher Hammer | |
| Construction Machinery Structural Parts | |
| Railway Components | |
| Crane Components | |
| Marine Hardware |
Quick Identification Of Three Casting Materials
By characteristics:
- Gray iron – brittle
- Ductile iron – tough
- Aluminum casting – light
- Cast steel – hard
By material grades / code number
- HT / GG / EN‑GJL = Gray cast iron
- QT / GGG / EN-GJS = Ductile cast iron
- ZL / YL / ADC / A356 / AlSi / EN AC / A380 = Cast aluminum
- ZG / WCB / CF8 / CF8M / GS / GP / 1.XXXX = Cast steel
Practice
Sort out the castings purchased daily by your company and mark which category they belong to.
