Planetary Gear Sets
Sun, planet and ring gear sets cut as a matched group, with the carrier if needed.
Planetary sets cut as a group, because load sharing across three planets only works if the teeth are matched. One gear out of the set carrying the load is how planetary drives fail early.
5–8 weeks
5 pieces
ISO 9001:2015 · IATF 16949
Technical Specifications
| Parameter | Value | Unit |
|---|---|---|
| Ratio range | 3:1–50:1 | per stage |
| Tooth quality | AGMA 9–12 | class |
| Load sharing | Matched set | - |
| Backlash | 0.05–0.15 | mm |
| Module range | 1–6 | module |
| Carrier | Machined to match | on request |
Available Materials
- Steel 8620 (case hardened)
- Steel 4140
- Bronze C932 (carrier bushings)
Typical Applications
- Wheel drives
- Winch gearboxes
- Robot joints
- Slewing drives
- Tool changers
Surface Finishes
- Case hardened
- Ground flanks
- Shot peened
- Phosphate coated
- Black oxide
Industries Served
- Industrial Equipment
- Automotive & EV
- Mining & Construction
- Robotics
- 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.
- Part size
- Module range at 1–6 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, Carbon Steel 8620 (case hardening), rates 7/10 on our machinability scale at 149–200 HB (as-supplied) · 58–62 HRC case after carburising. 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 5 pieces, 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
- First article inspection to AS9102, because this family carries an aerospace or automotive certificate
The full equipment list, with counts, is on the capability page; the inspection sequence is on quality and inspection.
Questions buyers ask
- Why must a planetary set be ordered as a set?
- Because the planets share the load only if their tooth thickness matches. Replace one planet from a different batch and it either takes all the load or none of it.
Related part families
Internal & Ring Gears
Internal gears shaped or ground in bores from 60–800 mm, for planetary and clutch drives.
Precision Spur Gears
AGMA 8–12 spur gears, hobbed and profile ground, from 12 mm to 800 mm pitch diameter.
Gearbox Assemblies
Housings, gears, bearings and seals built and run-in as one unit with backlash recorded.