PPE for your SRBs: Preventing common failures with adequate bearing protection

Anyone who has experienced sand in their eyes knows that even the tiniest abrasive particle can significantly irritate and damage a precision instrument. It’s common sense to wear sealed goggles if our work environment has highly abrasive dust and contaminants. And just as we protect our eyes, we must shield our machinery from contamination to prevent costly damage and downtime. Common failures do not have to be common Precision machinery, such as bearings, requires clean, controlled operating conditions to function correctly. Spherical roller bearings (SRBs) are one of the industry’s most widely used bearings due to their versatile features, such as heavy radial and axial load ratings and their ability to auto-compensate for misalignment. These attributes make SRBs a highly popular choice for installation in the harshest applications. They are often installed on high-load conveyors in remote or difficult-to-maintain locations where contamination risks are severe. Unfortunately, many operations experience premature failures in these challenging applications due to inadequate bearing protection (Figure 1). Consequently, some facilities have become accustomed to replacing their SRBs after just weeks of service. The consequences of inadequate protection Consider the example of a gold mine that experienced frequent bearing failures on its conveyors. In a reliability meeting, the maintenance team shared an image of a failed SRB assembly with me. Mounted on a large mine-duty conveyor pulley, the bearing was glowing red-hot as it ground through the side of the cast housing, with pieces of hot slag falling to the ground below. The conveyor pulley had been installed for only a few weeks. Our inspection revealed that the primary cause of failures was heavy contamination. These bearing failures were an ongoing headache for the mine. Replacing a bearing was a five-hour job, resulting in considerable production losses, hazardous conditions and an extremely high volume of replacement bearing purchases.