Why Lubricate Nylon?
Nylon’s natural surface properties include a relatively low coefficient of friction compared to many engineering plastics—but it’s not inherently self-lubricating. In moving-part applications like gears, bearings, slides, and cams, unlubricated nylon can experience accelerated wear, frictional heating, and stick-slip behavior. Lubricated nylon grades solve this by incorporating solid or liquid lubricants directly into the polymer matrix, creating parts that run smoothly for millions of cycles without external lubrication.
The lubricant additives work by forming a transfer film on the mating surface. As the nylon part moves, microscopic lubricant particles are released, coating both the nylon surface and the opposing metal or plastic surface. This film reduces the coefficient of friction from 0.35–0.40 (unmodified nylon on steel) down to 0.10–0.20, depending on the lubricant type and loading.
The Three Main Lubricant Types
| Lubricant | Typical Loading | COF (vs Steel) | Best Application |
|---|---|---|---|
| PTFE (Téflon) | 10–20% | 0.10–0.18 | High-speed bearings, low-load slides |
| MoS₂ (Molybdenum Disulfide) | 1–5% | 0.12–0.20 | High-load gears, thrust washers |
| Oil-filled | 2–8% | 0.08–0.15 | Precision bearings, low-noise applications |
PTFE-Filled Nylon
PTFE (polytetrafluoroethylene) is the most common solid lubricant for nylon. With a coefficient of friction as low as 0.04 in its pure form, PTFE particles dispersed throughout nylon create an extremely low-friction surface. PTFE-filled nylons are ideal for high-speed, low-to-moderate load applications where continuous sliding motion is required.
The limitation: PTFE reduces mechanical strength by 10–20% and increases cost. It also doesn’t perform as well as MoS₂ under very high contact pressures.
MoS₂-Filled Nylon
Molybdenum disulfide has a layered crystal structure similar to graphite—sheets that easily slide past each other. This makes it exceptional under high contact pressures where PTFE would be squeezed out. MoS₂-filled nylon is the go-to choice for gears, cams, and thrust washers operating under significant load.
MoS₂ also increases nylon’s crystallinity slightly, which can improve strength and stiffness—unlike PTFE which weakens the matrix. The dark gray/black color can be a consideration for visible parts.
Oil-Filled Nylon
Oil-filled nylons incorporate lubricating oil directly into the polymer during compounding. During operation, the oil slowly migrates to the surface, providing continuous lubrication throughout the part’s life. This “self-replenishing” characteristic makes oil-filled nylon excellent for sealed applications where relubrication is impossible.
Common oils include silicone, mineral oil, and synthetic hydrocarbon oils. The oil content is precisely controlled to avoid excessive migration that could contaminate surrounding components.
Wear Rate Comparison
| Nylon Grade | K-Factor (×10⁻⁸ mm³/N·m) | PV Limit (MPa·m/s) | Service Temp Range |
|---|---|---|---|
| PA6 Unfilled | 40–80 | 0.09–0.12 | -30°C to 85°C |
| PA6 + 15% PTFE | 5–12 | 0.15–0.25 | -40°C to 100°C |
| PA6 + MoS₂ | 8–15 | 0.20–0.35 | -30°C to 95°C |
| PA66 + Aramid + PTFE | 2–5 | 0.35–0.50 | -40°C to 120°C |
Design Guidelines for Lubricated Nylon Parts
- Surface finish of the mating part: Aim for 0.2–0.4 μm Ra on the steel/opposing surface. Rougher surfaces accelerate wear.
- Clearance: Allow 0.3–0.5% of the bearing diameter for thermal expansion and water absorption swell.
- Wall thickness: Maintain uniform wall thickness to avoid warpage that creates uneven wear patterns.
- Running-in period: Expect higher friction during the first 500–1000 cycles as the transfer film establishes.
- Combination with glass fiber: Adding glass fiber to lubricated nylon improves load capacity but increases wear on the mating surface. Use hardened steel (58+ HRC) for mating parts.
Pourquoi choisir le plastique Nylon pour vos besoins en plastique technique ?
- ✅ Plus de 300 machines de moulage par injection de 50T à 2000T
- ✅ Plus de 10 000 pièces par jour capacité de production
- ✅ Précision de ±0,02 mm tolérance pour tous les matériaux
- ✅ MOQ 1 pièce seulement pour le prototypage ; extensible à des millions d'exemplaires
- ✅ Devis 24 heures sur 24, Délais de livraison : 3 à 15 jours
- ✅ Système de gestion de la qualité certifié ISO 9001
Articles connexes
- Nylon vs POM (Acetal/Delrin): Choosing Between Two Engineering Plastics
- Propriétés des matériaux en nylon : Une référence technique complète
- Long Glass Fiber vs Short Glass Fiber Reinforced Nylon
FAQ
How do you know whether Lubricated Nylon Grades: PTFE, MoS₂ and Oil-Filled Options for Wear Applications fits a part?
Lubricated Nylon Grades: PTFE, MoS₂ and Oil-Filled Options for Wear Applications fits a part when its load capacity, temperature range, moisture exposure, wear behavior, and processing method match the real service conditions.
What properties should be checked for Lubricated Nylon Grades: PTFE, MoS₂ and Oil-Filled Options for Wear Applications?
Vérifier la résistance, la rigidité, la résistance aux chocs, la résistance à la chaleur, l'absorption d'humidité, la stabilité dimensionnelle, le frottement, l'usure et la compatibilité chimique.
What is the biggest selection risk for Lubricated Nylon Grades: PTFE, MoS₂ and Oil-Filled Options for Wear Applications?
Le plus grand risque est de choisir à partir d'une fiche technique sans tenir compte de l'environnement réel, de la méthode de traitement, de la géométrie de la pièce et de l'utilisation à long terme.
When should Lubricated Nylon Grades: PTFE, MoS₂ and Oil-Filled Options for Wear Applications be tested before production?
Les essais sont recommandés lorsque la pièce est soumise à une charge, à la chaleur, à des produits chimiques, à l'humidité, à des tolérances serrées, à des exigences réglementaires ou à un nouvel environnement de travail.
