Overview
POM gears, also known as acetal or Delrin gears, are precision polymer gearing components manufactured from polyoxymethylene (POM), a high-performance engineering thermoplastic valued for its excellent dimensional stability, low friction, wear resistance, and cost-effectiveness. These gears are widely used in office equipment, home appliances, automotive components, and industrial automation systems where reliable, quiet, and maintenance-free power transmission is required. OrroMFG produces high-precision POM gears using advanced CNC machining and injection molding techniques to deliver consistent quality and performance for medium-load applications.
POM gears offer an excellent balance of mechanical properties, chemical resistance, and cost, making them the workhorse of plastic gearing in many industries. They combine high stiffness and strength with excellent fatigue endurance and a low coefficient of friction, enabling efficient power transmission without external lubrication in many cases. Our POM gear product range includes both homopolymer (POM-H / Delrin) and copolymer (POM-C) formulations, each with specific advantages for different application requirements. We manufacture spur gears, helical gears, bevel gears, worm gears, and pinion gears in a wide range of sizes and configurations, from tiny instrument gears to larger industrial gears. POM gears are particularly well-suited for high-volume production through injection molding, offering excellent reproducibility and cost efficiency.
Key Features
- Excellent Dimensional Stability: Low moisture absorption and excellent creep resistance ensure precise gear geometry over time and varying environmental conditions.
- Low Friction and Wear: Inherently low coefficient of friction provides good wear resistance and enables dry-running operation in many applications.
- High Fatigue Resistance: Excellent fatigue endurance under repeated loading and cycling conditions.
- Good Mechanical Strength: High stiffness and tensile strength suitable for medium-load power transmission.
- Smooth and Quiet Operation: Damping properties reduce noise and vibration compared to metal gears.
- Cost-Effective: Excellent performance-to-cost ratio with high-volume manufacturing capability.
Material Specifications
| Property | POM-H (Homopolymer) | POM-C (Copolymer) | 25% Glass-Filled POM | PTFE-Filled POM |
|---|---|---|---|---|
| Density (g/cm³) | 1.40 - 1.42 | 1.41 - 1.43 | 1.60 - 1.65 | 1.45 - 1.55 |
| Tensile Strength (MPa) | 65 - 75 | 55 - 65 | 90 - 110 | 50 - 60 |
| Tensile Modulus (GPa) | 3.0 - 3.4 | 2.6 - 3.0 | 5.5 - 7.0 | 2.5 - 3.0 |
| Flexural Strength (MPa) | 90 - 100 | 80 - 90 | 130 - 150 | 70 - 80 |
| Flexural Modulus (GPa) | 2.8 - 3.2 | 2.4 - 2.8 | 5.0 - 6.5 | 2.2 - 2.6 |
| HDT at 1.8 MPa (°C) | 110 - 120 | 100 - 110 | 155 - 165 | 100 - 110 |
| Continuous Service Temp (°C) | 80 - 100 | 80 - 100 | 100 - 120 | 80 - 100 |
| Hardness (Rockwell M) | 78 - 85 | 75 - 82 | 90 - 100 | 70 - 78 |
| Coefficient of Friction | 0.15 - 0.25 | 0.15 - 0.25 | 0.20 - 0.30 | 0.08 - 0.15 |
| Water Absorption (24h, %) | 0.20 - 0.30 | 0.20 - 0.30 | 0.15 - 0.25 | 0.15 - 0.25 |
| Fatigue Limit (MPa, 10⁷ cycles) | 25 - 30 | 20 - 25 | 35 - 45 | 20 - 25 |
Applications
Office Equipment and Business Machines
POM gears are extensively used in office equipment including printers, copiers, scanners, fax machines, and shredders. They provide reliable, quiet operation for paper feed mechanisms, drive trains, and gear motor assemblies. Their excellent dimensional stability ensures consistent print quality and paper handling over millions of cycles. Typical applications include paper pickup gears, fuser drive gears, and scanner drive mechanisms.
Home Appliances
In household appliances, POM gears serve in washing machines, dishwashers, refrigerators, coffee machines, food processors, and microwave ovens. They are commonly found in timer mechanisms, motor drives, pump assemblies, and door latch mechanisms. POM’s resistance to water, detergents, and food products makes it well-suited for appliance applications. Its low friction and wear resistance contribute to long appliance service life with minimal maintenance.
Industrial Automation and Robotics
POM gears are widely used in industrial automation equipment including conveyor systems, packaging machinery, assembly lines, and small robotic systems. They are employed in actuators, stepper motor drives, conveyor drives, and positioning mechanisms. POM gears offer a cost-effective solution for moderate-load automation applications where quiet operation, low maintenance, and corrosion resistance are important.
Automotive Industry
POM gears find numerous applications in automotive systems including window regulators, wiper motors, seat adjusters, HVAC actuators, mirror adjusters, and fuel system components. Their ability to withstand temperature variations under the hood, resist automotive fluids, and operate quietly contributes to passenger comfort and vehicle reliability.
Consumer Electronics
In consumer electronic devices, POM gears are used in cameras, audio equipment, optical disk drives, gaming consoles, and smart home devices. Miniature PEEK gears provide precise motion control for zoom mechanisms, disk drives, and other precision mechanisms where small size, light weight, and quiet operation are essential.
Operating Conditions
- Temperature Range: -40°C to +100°C (-40°F to +212°F) continuous service; short-term up to 120°C
- PV Limit: Up to 2,000 bar·m/s under optimal conditions with PTFE-filled grades
- Speed Range: Up to 10,000 RPM depending on gear size, module, and material grade
- Torque Capacity: Up to 200 Nm depending on gear size, configuration, and material
- Chemical Compatibility: Resistant to hydrocarbons, solvents, fuels, lubricants, weak acids, and bases; good resistance to water and aqueous solutions
- Not Recommended For: Strong acids, strong oxidizing agents, hot water above 80°C continuous, and UV exposure (unfilled grades)
- Lubrication: Self-lubricating for light-to-moderate loads; grease lubrication recommended for higher loads and speeds
- Humidity Resistance: Good; low moisture absorption minimizes dimensional changes in humid environments
Material Comparison
| Material | Strength | Temp Range | Dimensional Stability | Cost | Best For |
|---|---|---|---|---|---|
| POM (Acetal) | Medium-High | -40 to +100°C | Excellent | Low-Medium | General industrial, appliances, office equipment |
| Nylon (PA66) | Medium-High | -40 to +120°C | Fair (moisture sensitive) | Low | High-impact, lubricated applications |
| PEEK | Very High | -40 to +260°C | Excellent | Very High | High-temp, high-load, medical/semiconductor |
| Steel | Very High | -40 to +200°C+ | Excellent | Medium | Heavy-duty, high-torque, high-load |
| Brass | Medium | -40 to +200°C | Excellent | Medium-High | Low-friction, corrosion-resistant apps |
| Nylon + MoS2 | Medium-High | -40 to +120°C | Fair | Low-Medium | High-wear, dry-running applications |
Choose POM gears when:
- Excellent dimensional stability and low creep are required
- Low friction and self-lubricating properties are needed
- Cost-effective performance for medium-load applications
- Quiet operation is important for consumer-facing products
- The application involves office equipment, appliances, or general industrial use
- Good fatigue resistance and long cycle life are required
Customization Options
- Material Grades: POM-H (homopolymer), POM-C (copolymer), glass-filled (10-30%), PTFE-filled, silicone-filled, UV-stabilized, impact-modified, and food-grade POM
- Gear Types: Spur gears, helical gears, bevel gears, miter gears, worm gears, rack and pinion, internal gears, face gears
- Size Range: Module 0.2 to Module 6; pitch diameter from 2mm to 300mm; bore sizes from 1mm to 80mm
- Quality Grades: AGMA Q8 to Q12; DIN 3962 Class 5 to 9; JIS N4 to N9
- Manufacturing Methods: CNC machined (prototyping and low volume), injection molded (high volume), 3D printed (rapid prototyping)
- Hub Configurations: Plain bore, keyway, set screw, D-bore, splined bore, hexagonal bore, press-fit hubs
- Tolerance Grades: IT5-IT8 for machined gears; IT7-IT10 for molded gears
- Surface Finishes: As-molded, machined, polished, tumbled, and deburred surfaces
- Color Options: Natural (ivory/white), black, gray, and custom colors for product aesthetics or grade identification
- Secondary Operations: Insert molding of metal hubs, shafts, and bearings; ultrasonic welding; and assembly services
Quality Assurance
OrroMFG maintains strict quality control standards throughout POM gear manufacturing. Our ISO 9001:2015 certified quality management system ensures consistent product quality from raw material sourcing through final inspection and packaging. For injection-molded gears, we employ scientific molding principles with real-time process monitoring to ensure part-to-part consistency and dimensional repeatability. For CNC-machined gears, we use precision gear hobbing and shaping equipment with in-process inspection capabilities.
Quality control procedures include incoming material testing to verify POM grade, melt flow index, and mechanical properties. In-process inspection covers tooth profile verification, pitch measurement, runout checking, and dimensional verification using coordinate measuring machines (CMM) and specialized gear measurement equipment. Final inspection includes comprehensive gear evaluation against AGMA or DIN standards, including tooth thickness, backlash, profile accuracy, lead variation, and surface roughness measurement. We also perform functional testing including wear testing, noise testing, and fatigue life testing for critical applications. All products are supplied with material certificates, inspection reports, and full batch traceability documentation. Our commitment to quality ensures that every POM gear we produce delivers reliable, consistent performance throughout its service life.
