Bearing Knowledge

The main factors causing premature failure due to bearing vibration

The factors affecting the performance of rolling bearings primarily refer to whether installation and alignment, operation and maintenance, and repair work comply with technical requirements. In accordance with the technical requirements for bearing installation, operation, maintenance and servicing, the loads, rotational speed, operating temperature, vibration, noise and lubrication conditions of rolling bearings in operation must be monitored and inspected. Should any abnormalities be detected, the cause must be identified immediately and adjustments made to restore normal operation. Installation conditions are one of the primary factors affecting bearing performance. Improper installation often alters the force distribution between the various components of the bearing assembly, causing the bearing to operate under abnormal conditions and leading to premature failure.

Internal factors primarily refer to the three key elements that determine bearing quality: structural design, manufacturing processes and material quality. Factor 1: Improper Installation (accounting for approximately 16%)

1. The use of excessive force during installation, such as striking tapered roller bearings directly with a hammer, causes significant damage to the bearings and is a primary cause of deformation.

2. Incomplete or misaligned installation, or failure to seat the bearing fully in its housing, results in excessively tight clearance in the tapered roller bearing. If the inner and outer rings are not aligned on the same rotational axis, this leads to misalignment.

Recommendation: Select appropriate or specialised bearing installation tools, and use dedicated instruments to verify the fit after installation.

II. Inadequate Lubrication (approx. 50%)

Surveys indicate that inadequate lubrication is one of the primary causes of premature bearing failure. Key factors include: failure to replenish lubricant or grease in a timely manner; insufficient application of lubricant or grease; inappropriate selection of lubricant or grease; and incorrect lubrication methods, amongst others.

Recommendation: Select the correct lubricant or grease and employ the appropriate lubrication method.

III. Contamination (approximately 14%)

Contamination can also lead to premature failure of rolling bearings. Contamination refers to the ingress of sand, dust, metal shavings, etc., into the bearing interior. The main causes include: opening the packaging of tapered roller bearings too early prior to use, resulting in contamination; a dirty working environment during installation, resulting in contamination; a dirty operating environment for the bearing, or contamination of the working medium, etc.

Recommendation: Do not open the bearing packaging before use; maintain a clean installation environment and clean the bearings to be used; and enhance the bearing sealing arrangements.

Recommendation: Select the appropriate bearing type and replace fatigued bearings regularly and promptly.

IV. Fatigue (approximately 34%)

Fatigue failure is a common form of bearing damage. Common causes of fatigue failure may include: long-term operation of the bearing under excessive loads; failure to carry out maintenance in a timely manner; improper maintenance; and ageing of the equipment.