The service life of single row tapered roller bearings is usually within the theoretical range of 20000 to 80000 hours, but the actual life is affected by multiple factors such as load, speed, lubrication, installation accuracy, material quality, and working environment, and needs to be calculated through formulas or evaluated through experiments. The following is a detailed explanation of its service life:
1. Theoretical service life range
Under ideal conditions (such as appropriate load, speed, lubrication, and environment), the theoretical service life of a single row tapered roller bearing is usually between 20000 and 80000 hours. However, this range is not absolute, and the actual lifespan may vary depending on specific application scenarios.
2. Key factors affecting service life
Load:
Overload accelerates raceway fatigue, and for every 10% increase in dynamic equivalent load, the service life may decrease by about 37% (cubic inverse relationship).
. Conical roller bearings can withstand both radial and axial loads simultaneously, but the magnitude of the axial load is affected by the contact angle.Speed:
The bearing life under high-speed operation is generally shorter than that under low-speed conditions.
. Centrifugal force (proportional to the square of the rotational speed) will affect the load distribution. When the DN value (the product of the bearing inner diameter and the rotational speed) exceeds the limit, special design is required. Lubrication: Adequate lubrication directly affects the friction coefficient and heat generation level. Insufficient oil film thickness can lead to metal to metal contact, causing early peeling failure. The appropriate lubricant and lubrication method are crucial for the lifespan of bearings. Installation accuracy: Installation errors can cause stress concentration. For example, the axial deviation of a tapered bearing should be ≤ 0.05mm, and the perpendicularity of the shoulder of a ball bearing should be ≤ 0.01mm. Incorrect installation methods can cause excessive internal stress in the bearing, reducing its lifespan.Material quality:
The quality of bearing materials directly affects their fatigue strength and wear resistance.
. For every level increase in inclusion grade (evaluated according to ASTM E45), the lifespan may decrease by 20% -30%.Working environment:
Environmental factors such as temperature, humidity, and pollution level can also affect the lifespan of bearings.
. For example, long-term temperatures exceeding 120 ℃ can cause surface tempering softening and reduce material hardness. Particles with a diameter greater than the thickness of the lubricating film will be pressed into the raceway to form a stress source, accelerating wear.