THK Grease AFA VS AFC: Which is better for high-load linear guides?

author: Anna

2025-05-13

When selecting between THK AFA and THK AFC greases for high-load linear guide applications, it's essential to consider their specific properties and suitability for your operational conditions.

? Technical Comparison

Feature	THK AFA Grease	THK AFC Grease
Base Oil	High-grade synthetic oil	High-grade synthetic oil
Thickener	Urea-based	Urea-based
Kinematic Viscosity (40°C)	25 mm²/s	25 mm²/s
Operating Temperature Range	-45°C to +160°C	-54°C to +177°C
4-Ball Weld Load	3089 N	3089 N
Key Features	Low sliding resistance - Excellent water resistance - Suitable for high-speed, long-stroke operations	Excellent fretting corrosion resistance - Wide operating temperature range - Suitable for micro-vibration conditions
Color	Brown	Brown

? Application Suitability

THK AFA Grease:
- Best For: High-speed, long-stroke linear motion systems where low sliding resistance is crucial.
- Advantages: Its low kinematic viscosity and excellent water resistance make it ideal for environments where moisture ingress is a concern.
THK AFC Grease:
- Best For: Applications prone to micro-vibrations and fretting corrosion, such as precision positioning systems.
- Advantages: The inclusion of special additives provides superior fretting resistance, and its broader temperature range offers versatility in various operating conditions.thk.com tuli-shop.com+1thk.com+1

✅ Recommendation

For high-load linear guides, THK AFC Grease is generally more suitable due to its enhanced fretting corrosion resistance and broader operating temperature range. These properties ensure better protection under heavy loads and in environments where temperature fluctuations are significant.

However, if your application emphasizes high-speed and long-stroke movements with concerns about water exposure, THK AFA Grease would be the preferred choice.