Main Functions of Lubricants
Main Functions of Lubricants
2022年3月24日
How to Judge the Failure of Bearing Grease in Use
How to Judge the Failure of Bearing Grease in Use
2022年3月24日

Maintenance of Abnormal Sound of Bearing Raceway

  • Raceway sound of bearing and its control method raceway sound is a smooth and continuous sound made by the rolling body rolling on the raceway surface when the shaft is running. It is a unique basic sound that will occur in all bearings. The general bearing sound is the sound of raceway plus other sounds. 
  • The greater the rigidity of the bearing pedestal, the lower the sound pressure level of the raceway sound. If the radial clearance is too small, the sound pressure level and dominant frequency of raceway sound will increase sharply with the decrease of radial clearance.
  • Bearing fatigue failure is a surface form of failure, which is mainly manifested in the initiation, propagation and fracture process of fatigue crack, and the long-term impact of load failure under alternation.

Maintenance of Abnormal Sound of Bearing Raceway

  • 1. Reason: the accuracy of the integral eccentric bearing is low. Method: select the bearing with the specified accuracy grade
  • 2. Cause: the main shaft is bent or the box hole is not concentric. Method: repair the main shaft or box
  • 3. Cause: the belt is too tight. Method: adjust the belt to make it elastic properly
  • 4. Cause: poor lubrication method: select the specified brand of lubricating materials and clean them properly
  • 5. Cause: low assembly quality method: improve assembly quality
  • 6. Cause: the inner shell of the bearing runs. Method: replace the bearing and related worn parts
  • 7. Method of excessive axial force: clean and adjust the clearance of sealing ring between 0.2 ~ 0.3mm, correct the diameter of impeller balance hole and verify the static balance value
  • 8. Bearing damage method: replace the bearing
Maintenance of Abnormal Sound of Bearing Raceway
  • The methods to control the sound of raceway are: select low-noise bearings, that is, bearings with small waviness, and carefully select the service conditions. Raceway noise often affects the noise of the whole machinery. Reducing raceway noise can reduce the noise of the whole machinery.
  • Age hardening: the phenomenon that the consistency of lubricating grease increases with storage time. Appearance: the characteristics of lubricating grease seen only by visual inspection, usually including overall appearance, texture, color and luster.
  • Overall appearance: smooth, rough, granular, oily, etc.Maintenance of Abnormal Sound of Bearing Raceway
  • Texture: creamy, elastic, brushed.Maintenance of Abnormal Sound of Bearing Raceway
  • Color: red, blue, yellow, white, etc., with restricted adjectives such as “light”, “medium”, “deep”, etc.
  • Gloss: shiny, dull, etc.Maintenance of Abnormal Sound of Bearing Raceway
  • Consistency: consistency refers to the degree to which plastic substances resist deformation under the action of external forces.Maintenance of Abnormal Sound of Bearing Raceway
  • Cone penetration: cone penetration is a measure of grease consistency. The greater the cone penetration, the softer the grease.
  • Consistency grade: nlgi (American grease Association) is divided into nine grades, from 000 to 6.
  • Mechanical stability: the ability of lubricating grease to resist the change of consistency when subjected to mechanical shear. The smaller the change of consistency, the better the mechanical stability.
  • Thixotropy: when the grease is sheared, the consistency decreases, and when the shearing is stopped, the consistency increases again.Maintenance of Abnormal Sound of Bearing Raceway
  • Water resistance: the ability of lubricating grease to resist washing out from the bearing, the ability to resist the structural damage of grease due to water absorption, and the ability to prevent metal surface corrosion in the presence of water.
  • Colloidal stability: the ability of lubricating grease to resist oil separation.
  • Similar viscosity: generally, the viscosity of lubricating grease decreases with the increase of shear speed, so the grease viscosity is called similar viscosity or apparent viscosity.Maintenance of Abnormal Sound of Bearing Raceway
Technical requirements for Timken non-standard bearing