Inspection of QJ Series Bearing

 

To inspect a QJ bearing, which is a type of four-point contact ball bearing commonly used in applications requiring high radial and axial loads, you should follow a systematic process to ensure its condition and determine if it can be reused. Here are the steps to inspect a QJ bearing:

1. Initial Inspection:
• Begin by recording the appearance of the QJ bearing and checking the amount and condition of the residual lubricant.
• Clean the bearing using an appropriate cleaning solution such as light oil or kerosene. Ensure that the cleaning solution effectively removes any lubricant and deposits from the bearing.
2. Preliminary Cleaning:
• Dismount the QJ bearing and give it a preliminary cleaning using an oil bath. Use a soft brush or similar tool to remove initial contaminants from the bearing.
• Avoid rotating the bearing with foreign matter present, as this can damage the raceways.
3. Finishing Rinse:
• After rough cleaning, perform a finishing rinse by rotating the QJ bearing while keeping it immersed in rinsing oil. This step ensures thorough cleaning of the bearing surfaces.
• Always keep the rinsing oil clean to prevent recontamination of the bearing.
4. Examination Process:
• Once cleaned, carefully examine the condition of the QJ bearing raceways, external surfaces, cage wear, internal clearance, and tolerances.
• Check for any damage, abnormalities, or signs that may indicate whether the bearing can be reused.
5. Specific Checks for QJ Bearings:
• For QJ bearings, which are separable bearings with four points of contact, individually examine their rolling elements and outer ring raceway.
• Ensure that each component is in good condition without cracks, flaking, significant wear, or other issues that would prevent reuse.
6. Final Assessment:
• Consider factors such as degree of wear, machine function, importance of the bearing in operation, operating conditions, and time until next inspection when determining whether to reuse the QJ bearing.
• If any critical issues like cracks, flaking, significant wear, rust, heat damage, or other listed abnormalities are present, replacement rather than reuse is necessary.

By following these steps and conducting a thorough inspection based on these guidelines specific to QJ bearings, you can assess the condition of your bearings accurately and make informed decisions regarding their reuse.