What are some common mistakes when installing Pneumatic Roofbolters bearings?

I. Incorrect Force Application Method (Most Frequent)

1. Direct Force Transmission Through Rolling Elements: During installation, tapping the outer ring to move the inner ring into position transmits the force through the rolling elements, directly damaging the raceway and rolling elements, creating a risk of early failure.

2. Direct Impact on the Bearing Outer/Inner Ring: Directly striking the bearing with a hammer causes impact loads that can lead to raceway indentation, rolling element scratches, and may even cause cage deformation or breakage. In severe cases, abnormal noise and jamming may occur immediately after installation.

3. Uneven Force Application: Tapping the bearing from one side causes uneven force application, tilting the bearing rings and causing overload on one side of the raceway, leading to early fatigue failure. It also results in uneven preload, causing abnormal operating temperature rise and vibration.

II. Installation Operation Errors

1. Reversed Installation Direction: Installing the bearing in a direction other than the original bearing markings, especially with special bearing structures, can lead to abnormal clearance, uneven force distribution, and significantly shortened service life.

2. Using old bearings as installation punches: Using old bearings as pads to hammer new bearings during installation can damage the mating surfaces of the new bearing due to deformation and burrs, leading to secondary damage.

3. Directly heating bearings with a flame: Heating bearings with a flame for easier installation causes localized annealing of the bearing steel, reducing hardness and wear resistance, and significantly shortening the bearing's rated life.

4. Installing without inspection and cleaning: Failure to clean impurities and oil from the shaft and mounting holes before installation allows impurities to enter the bearing, causing abrasive wear. Statistics show that abrasive wear accounts for 14% of bearing failures and severely shortens service life.

III. Lubrication and Pretreatment Errors

1. Adding too much or too little lubricating grease: Adding too much grease can cause excessive bearing temperature rise, while insufficient grease can cause dry friction, both accelerating bearing wear.

2. Failure to check preload: For bearings requiring preload, such as angular contact bearings, failure to check and adjust the preload after installation can lead to uneven preload, causing abnormal temperature rise and vibration, resulting in premature failure.

3. Neglecting seal inspection: Damaged seals were not inspected and replaced during bearing installation, which allowed foreign matter to enter the lubricant later, accelerating bearing wear and failure.