Nylon
Polyamide (PA) Bearing Material
A versatile engineering plastic for light-duty bearings. Nylon offers self-lubricating properties, low cost, and excellent wear resistance for applications where load and temperature requirements permit.
What is Nylon?
Nylon is the common name for a family of synthetic polymers called polyamides (PA). Developed by DuPont in 1935, nylon was one of the first engineering plastics and remains widely used in bearing applications today due to its combination of strength, wear resistance, and low friction.
In bearing applications, nylon serves as a cost-effective alternative to more advanced materials like PTFE and POM for light-to-medium duty applications. Nylon bearings can operate without lubrication in many applications, though their performance improves significantly with initial greasing or oil impregnation.
For applications requiring higher load capacity or operating temperature, consider JBM's PTFE composite bushings or POM composite bushings, which offer superior performance in demanding conditions.
Nylon Bearing Advantages
Self-lubricating — can run dry in light loads
Excellent abrasion resistance for plastics
87% lighter than bronze
Economical for high-volume production
Nylon 66 Properties
| Chemical Name | Polyamide 66 |
| Abbreviation | PA66 / Nylon 66 |
| Density | 1.14 g/cm³ |
| Melting Point | 260°C (500°F) |
| Max Service Temp | +100°C (continuous) |
| Tensile Strength | 70-85 MPa |
| Hardness | Rockwell R118 |
| Friction (Dry) | 0.20 - 0.40 |
| Water Absorption | 2.5% (24h) |
Types of Nylon for Bearings
Different nylon grades and modifications offer varying performance characteristics for bearing applications.
PA6 (Nylon 6)
General PurposeCast nylon with excellent toughness and impact resistance. Easier to process than PA66. Good for large parts and general-purpose bushings.
- Tensile: 70 MPa
- Max Temp: 90°C
- Cost: Low
Use for: Rollers, guides, wear strips, light bushings
PA66 (Nylon 66)
Higher PerformanceHigher melting point and better mechanical properties than PA6. The standard for injection-molded bearing components. Better dimensional stability.
- Tensile: 85 MPa
- Max Temp: 100°C
- Cost: Low-Medium
Use for: Standard bushings, cage materials, small components
PA66 + Glass Fiber
ReinforcedGlass fiber reinforcement (typically 30%) dramatically increases strength, stiffness, and temperature resistance. Reduced creep under load.
- Tensile: 180 MPa
- Max Temp: 130°C
- Cost: Medium
Use for: Structural bushings, high-load applications, elevated temps
PA + MoS₂
LubricatedMolybdenum disulfide filler reduces friction and improves dry-running performance. Better wear life than unfilled nylon in unlubricated applications.
- Friction: 0.15 - 0.25
- Wear: 3x better
- Cost: Medium
Use for: Dry running bushings, slides, cam followers
Oil-Filled Nylon
Self-LubricatingNylon impregnated with lubricating oil during casting. Oil slowly releases during operation, providing continuous lubrication. True self-lubricating capability.
- Friction: 0.10 - 0.20
- Oil Content: 3-6%
- Cost: Medium
Use for: Maintenance-free applications, conveyors, food equipment
PA46 (Stanyl)
High TemperaturePremium high-temperature nylon. Maintains mechanical properties at elevated temperatures where standard nylons fail. Better chemical resistance.
- Tensile: 100 MPa
- Max Temp: 150°C
- Cost: High
Use for: Under-hood automotive, high-temp industrial applications
Nylon vs. Other Bearing Plastics
How does nylon compare to other engineering plastics commonly used in bearings?
| Property | Nylon (PA66) | PTFE | POM (Acetal) | UHMWPE |
|---|---|---|---|---|
| Friction Coefficient | 0.20 - 0.40 | 0.04 - 0.10 | 0.15 - 0.35 | 0.10 - 0.20 |
| Load Capacity | Medium (40 N/mm²) | Low-Medium | High (80 N/mm²) | Medium |
| Max Temperature | +100°C | +280°C | +110°C | +80°C |
| Water Absorption | High (2.5%) | None | Low (0.2%) | None |
| Dimensional Stability | Fair | Poor (creep) | Excellent | Good |
| Wear Resistance | Excellent | Fair | Good | Excellent |
| Impact Resistance | Excellent | Good | Good | Excellent |
| Cost | Low | Medium | Medium | Medium |
| Best For | Dry environments, light loads | Chemical, high temp | Precision, wet | Abrasive, food |
Need Better Performance?
If nylon's water absorption or temperature limits are concerns, consider upgrading to JBM's metal-polymer composite bearings:
✓ Nylon Advantages
- Low Cost: Most economical engineering plastic for bearings
- Self-Lubricating: Can run dry in light-load applications
- Wear Resistant: Excellent abrasion resistance
- Impact Tough: Absorbs shock loads well
- Lightweight: 87% lighter than bronze
- Quiet Operation: Damping properties reduce noise
- Chemical Resistant: Resists oils, fuels, many chemicals
- Easy to Machine: Can be machined to precise tolerances
✗ Nylon Limitations
- Water Absorption: Absorbs 2-3% moisture, causing swelling and strength loss
- Temperature Limited: Max 100°C continuous (less than PTFE/POM)
- Dimensional Changes: Swells with moisture, shrinks when dry
- Lower Load Capacity: Not suitable for heavy-duty applications
- Higher Friction: 2-5x higher friction than PTFE
- UV Sensitive: Degrades with prolonged sunlight exposure
- Creep Under Load: Deforms over time under constant stress
- Acid Sensitive: Attacked by strong acids
Where Nylon Bearings Work Well
Nylon bearings excel in light-to-medium duty applications where cost is a priority and environmental conditions are moderate.
Textile Machinery
- Spindle bearings
- Guide rollers
- Thread guides
- Shuttle bushings
- Cam followers
Conveyor Systems
- Idler rollers
- Guide rails
- Chain guides
- Wear strips
- Sprocket bushings
Office Equipment
- Printer bearings
- Copier components
- Paper feed guides
- Scanner mechanisms
- Chair casters
Furniture & Hardware
- Drawer slides
- Door hinges
- Cabinet hardware
- Folding mechanisms
- Adjustment knobs
Packaging Equipment
- Carton guides
- Bottle handling
- Label applicators
- Film rollers
- Accumulator tables
Agricultural Equipment
- Chain guides
- Idler wheels
- Auger bushings
- Conveyor bearings
- Adjustment mechanisms
Designing with Nylon Bearings
Account for Moisture
Nylon swells up to 3% with moisture absorption. Design clearances 0.05-0.10mm larger than for metal bearings. Use "dry as molded" dimensions and verify after conditioning.
Limit PV Value
Keep pressure × velocity (PV) below 0.10 N/mm²·m/s for dry running, 0.46 N/mm²·m/s with lubrication. Exceeding these limits causes rapid wear and heat buildup.
Consider Reinforcement
For higher loads, use glass-filled nylon (30% GF). This doubles strength and reduces creep, but increases shaft wear — use hardened or stainless shafts.
Shaft Compatibility
Nylon works best against hardened steel (HRC 55+) or chrome-plated shafts. Avoid soft aluminum or unhardened steel — friction and wear increase significantly.
Initial Lubrication
Even "self-lubricating" nylon benefits from initial greasing. A thin film of grease extends bearing life 2-3x and reduces break-in wear.
Temperature Derating
Reduce allowable load by 50% at 80°C, 75% at 100°C. If operating near temperature limits, consider PA46 or upgrade to PTFE/POM composites.
✓ Use Nylon When:
- Loads are light to moderate (<40 N/mm²)
- Operating temperature stays below 100°C
- Environment is dry (indoor, climate controlled)
- Cost is a primary consideration
- Quiet operation is important
- Impact or shock loads are present
- Weight reduction is beneficial
- Parts are produced in high volume
✗ Avoid Nylon When:
- Environment is wet or humid (use POM or PTFE)
- Temperature exceeds 100°C (use PTFE)
- Loads are heavy (use bronze or metal-polymer)
- Precision tolerances are critical (use POM)
- Lowest friction is required (use PTFE)
- Strong acids are present
- Outdoor UV exposure is expected
- Continuous high stress with creep concerns
Not sure if nylon is right for your application? Our engineers can recommend the optimal bearing material.
Contact EngineeringNeed Higher Performance?
While nylon works well for light-duty applications, JBM specializes in metal-polymer composite bearings that offer superior load capacity, temperature resistance, and dimensional stability. Upgrade to PTFE or POM composites for demanding applications.
View Composite Bearings