Sleeve bearing fans use a porous, oil-impregnated sleeve that surrounds the motor shaft. They are generally quieter and more cost-effective but have a shorter lifespan, typically rated for 30,000-40,000 hours.
Ball bearing fans use steel balls to reduce friction between the shaft and housing. They offer longer life (50,000-70,000+ hours), can operate at higher temperatures, and can be mounted in any orientation. They are slightly more expensive and may produce more noise at high speeds.
For continuous operation or high-temperature environments, ball bearing fans are recommended. For cost-sensitive, low-stress applications, sleeve bearing fans provide good value.
