Overview
POM spur gears are precision-machined gears used to transmit motion and torque quietly in appliances, automotive systems, office equipment, and industrial machinery. Acetal’s low friction, high fatigue strength, and excellent machinability make it the leading polymer for small-to-medium gears that run with minimal lubrication.
ORRO Manufacturing produces POM spur gears by CNC hobbing and shaping from acetal stock, holding tight pitch, profile, and bore tolerances for smooth, quiet transmission. We machine gears with integral hubs, keyways, and lightening holes, and can match tooth geometry to your mating gear for correct backlash.
Material Properties
| Property | POM (Acetal Homopolymer) |
|---|---|
| Density (g/cm³) | 1.41 - 1.42 |
| Tensile Strength (MPa) | 60 - 70 |
| Flexural Modulus (GPa) | 2.5 - 3.0 |
| Hardness (Rockwell M) | 80 - 88 |
| Max Continuous Temperature (°C) | 90 - 100 |
| Coefficient of Friction (vs. steel) | 0.20 - 0.35 |
| Fatigue Endurance | Excellent |
| Water Absorption (%) | 0.2 - 0.5 |
Key Advantages
- Quiet, Smooth Transmission: Low friction and good damping reduce gear noise versus metal gears.
- High Fatigue Strength: Withstands repeated tooth loading in continuous service.
- Self-Lubricating: Runs with minimal or no lubrication in many applications.
- Dimensional Stability: Low moisture absorption keeps tooth fits and backlash consistent.
- Corrosion and Chemical Resistance: Unaffected by moisture and many industrial fluids.
- Lightweight: Reduces inertia and load on bearings in high-speed drives.
Typical Applications
Appliances and Power Tools
Gears in mixers, printers, power tools, and small household appliances.
Automotive Mechanisms
Window regulators, seat adjusters, and latch mechanisms that need quiet, long-life gears.
Industrial and Office Equipment
Drive gears in conveyors, copiers, and packaging machinery.
Machining Capabilities
| Parameter | Capability |
|---|---|
| Tolerance | ±0.02 mm (bore), AGMA 8-10 tooth quality |
| Surface Finish | Ra 0.8 - 1.6 μm |
| Size Range | 10 mm to 250 mm diameter |
| Key Processes | CNC hobbing, shaping, turning, milling |
Application Case
Printer drive spur gear, POM — An office-equipment maker needed quiet spur gears with tight backlash to replace noisy metal gears in a printer drive train. ORRO hobbed POM gears to AGMA 9 tooth quality with a ±0.02 mm bore, delivering 30,000 gears in 18 days. The acetal gears reduced drive noise by 6 dB and cut component cost by 35%.
