Worm Gears & Wheels
Worm shafts and bronze wheels cut to matched centre distance, for high-ratio right-angle drives.
Worm drives for high ratios in a small envelope - a single stage gives 20:1 or more. The wheel is bronze against a hardened steel worm, because the pair is designed to wear on the softer part.
5–7 weeks
5 pieces
ISO 9001:2015
Technical Specifications
| Parameter | Value | Unit |
|---|---|---|
| Ratio range | 10:1–100:1 | single stage |
| Module range | 1–6 | module |
| Worm hardness | 58–62 | HRC |
| Centre distance | ±0.02 | mm |
| Lead angle | To 20 | ° |
| Wheel material | Centrifugal bronze | - |
Available Materials
- Bronze C932 / C90700 (wheel)
- Steel 8620 hardened (worm)
- Steel 4140
- Cast iron GGG40 (wheel)
Typical Applications
- Winches and hoists
- Rotary tables
- Conveyor drives
- Gate and barrier mechanisms
- Steering gearboxes
Surface Finishes
- Ground worm
- Hobbed wheel
- Case hardened
- Phosphate coated
- Black oxide
Industries Served
- Industrial Equipment
- Agricultural Machinery
- Marine
- Mining & Construction
- Rail
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
- Rockwell hardness tester on the part, not only against the mill certificate
The full equipment list, with counts, is on the capability page; the inspection sequence is on quality and inspection.
Questions buyers ask
- Why is the wheel bronze and the worm steel?
- So the wear lands on the part that is cheap to replace. Two hardened steel surfaces in sliding contact gall and seize; bronze against hardened steel runs in and wears predictably.
- What sets the centre distance tolerance?
- The backlash and the contact pattern. Get it wrong and the drive runs on the tooth edge, which is why we cut the wheel to match the worm it will actually run with.
Related part families
Helical Gears
Helical gears to AGMA 9–12 with ground flanks, for quieter drives and higher tooth loads.
Bevel & Miter Gears
Straight and spiral bevel gears for right-angle drives, lapped in pairs to a matched contact pattern.
Gear Housings
Machined gearbox housings with bored bearing seats, held to centre-distance ±0.02 mm.