Premature bearing failure is one of the more common conveyor roller failure modes, resulting in unscheduled shutdowns and maintenance costs. Thankfully with the right sealing design this problem can be avoided.
The biggest threat to the bearing is contamination.
Once solid contaminants such dust enters the bearing, they can get caught under the ball bearings, creating micro indentations and small fragments. Over time this promotes pitting corrosion and causes a chain event that cannot be reversed.
Fluids entering the bearing will not only dilute the grease but promote corrosion, again a chain event that cannot be reversed. Both solid and liquid forms of contaminant will result in a seized bearing days-months after entering.
Close to failure, the bearing temperature will increase and drag will increase. Eventually, the bearing will seize and stop rotating where it will either flog-out the bearing housing (housing spins without the bearing rotating) or the shell will become fixed.
Both scenarios can force unscheduled shuts to protect the belt.
High Performance PROK HDPE Seal
Investing in high quality conveyor rollers with the right seal will mitigate the risks associated with premature bearing failure.
PROK HDPE seal uses the proven seal of the PROK Steel Hybrid range. A superior seal design, the HDPE seal arrangement prevents solid and liquid contaminants from entering the bearing.
Designed for the toughest conditions and climates, PROK HDPE utilises a packaged seal that incorporates a labyrinth and an internal seal moulded with a low-friction stainless steel running face that is positioned against a contact seal.
An effective multi-labyrinth seal helps prevent ingress of dirt into the bearing, resulting in longer service life.
It optimises seal efficiency, correct bearing fits and lubrication to maintain drag at acceptable levels – without compromising roller life or capacity.
By investing in the right seal, mining companies are able to keep their conveyor running for longer and achieve production targets.
In collaboration with SKF, PROK HDPE utilises shielded 2Z bearings which are extremely effective at preventing contaminants from entering the bearing when exposed over small periods.
2RS bearings are effective at protecting intermittent exposure to contaminants, however not designed to handle constant exposure to contaminants.
The best approach is to prevent contaminants from making it to the bearing, 2RS seals are a last resort seal. PROK has taken this information and conducted internal water tests finding 2RS had worse seal performance than shielded 2Z.
Longer roller life, reduced maintenance costs
Improved seals reduce the likelihood of the roller forcing an unscheduled shut and result in longer roller life, which in the long run has huge benefits to the mining companies bottom line.
PROK are the market leaders in roller technology and have a proven product range to assist in optimising conveyor performance.
To find out more about PROK HDPE visit prok.com/hdpe