Cast Iron Gears
GG25 and GGG40 gears for large, slow drives, cast to shape and then cut.
Cast iron for big, slow gears where a steel blank would be expensive and unnecessary. It damps vibration better than steel, which matters on a large slow wheel.
6–10 weeks
1 piece
ISO 9001:2015
Technical Specifications
| Parameter | Value | Unit |
|---|---|---|
| Module range | 4–16 | module |
| Tooth quality | AGMA 7–9 | class |
| Diameter range | Ø300–Ø2500 | mm |
| Bore tolerance | H7 | - |
| Damping | Better than steel | note |
| Cast or fabricated blank | Cast | standard |
Available Materials
- Cast iron GG25
- Ductile iron GGG40
- GGG60
Typical Applications
- Large reduction gears
- Crusher and mill drives
- Crane gears
- Pump drives
- Agitator gears
Surface Finishes
- As-cut
- Painted
- Machined bore and keyway
- Balanced (on request)
Industries Served
- Mining & Construction
- Energy & Oil & Gas
- Water Treatment
- Industrial Equipment
- Marine
What drives the price of this part
Derived from the callouts on this page. Where a driver is not on the drawing, it is not on this list.
- Tolerance
- Bore tolerance at H7 is the tightest callout this family carries. Tightening a callout is a process decision, not a machining decision: below the standard ±0.005 mm the work moves to grinding or jig boring, and the price moves with it.
- Part size
- Module range at 4–16 module decides which machine the part lands on and how many setups it needs. Size is the driver buyers most often leave out of a first enquiry, and it is the one that changes the quote fastest.
- Material
- The first material listed, Ductile Iron GGG40 (EN-GJS-400-15, 60-40-18), rates 6/10 on our machinability scale at 160–210 HB. On this shop's scale a harder alloy means slower passes and more tool changes, and that is cycle time the quote has to carry.
- Order size
- Minimum order is 1 piece, so on a first order setup and programming are spread over very few parts and they are most of the price. Repeat orders at the same quantity are cheaper without anything on the drawing changing.
See how cycle time is calculated in the machining time calculator and what else moves a price in the cost driver reference.
How these parts are inspected
Matched to the callouts above and the instruments actually on the floor.
- Coordinate measuring machine (Zeiss CONTURA G2, two machines, GR&R 8.4% on the critical feature)
- Dimensional report against the drawing, with a 100% check on critical features rather than a sample
- Certificate of conformance and the mill certificate with every shipment
- Bore gauges and an optical comparator for hole position and edge form
The full equipment list, with counts, is on the capability page; the inspection sequence is on quality and inspection.
Questions buyers ask
- Why use cast iron for a large gear?
- Cost and damping. A 2 m steel gear is a forging problem; a cast iron one is a pattern job, and the material soaks up vibration that would otherwise show as noise and tooth wear.
Related part families
Internal & Ring Gears
Internal gears shaped or ground in bores from 60–800 mm, for planetary and clutch drives.
Gear Blanks
Turned and hardened gear blanks with the bore and faces finished, ready for cutting or grinding.
Gear Housings
Machined gearbox housings with bored bearing seats, held to centre-distance ±0.02 mm.