How does solid lube extend bearing life?
Solid lubrication – or permanent lubrication, as we’ve taken to calling it – is a game-changer for mounted bearings. Permanent lubrication is a replacement for standard grease lubrication, which still must happen manually or through complicated and expensive lubrication systems.
Lubrication-related issues are the largest cause of bearing failures. The industry is ready for change.
Bearing life is dependent on a multitude of factors, only one of which is lubrication. The resulting load, the speed at which the bearing runs, environmental factors, and quality of materials are a few others. Can a single solution solve every single one of these issues? Unfortunately, this is not the case. BUT, by selecting a bearing with permanent lubrication, you mitigate several of the more destructive forces that come along with power transmission.
Below, we’ll discuss the features that make permanent lubrication an outstanding choice. We’ll also talk about how those same features extend bearing life.
How does permanent lubrication work?
Permanent lubrication is a polymer material that contains micro-pores as small as one ten-thousandth of an inch. These micro-pores hold oil within them and contain as much as four times the base oil as a standard greased bearing. As the bearing begins operation, oil is released, providing lubrication to the rolling elements. Once the bearing comes to rest, these pores re-absorb the oil.
The polymer material completely fills the bearing cavity but does not impede the rolling elements from any movement. While aiding in lubrication, the polymer revolves within the races along with the ball bearings and cage. This allows the polymer to also act as an additional seal of sorts, by surrounding the bearings while lending structural integrity to the bearing seals.
With so few manufacturers offering permanent lubrication as an option, it is still relatively unknown throughout the industry. Before we can determine how permanent lubrication can positively affect a bearing, it’s helpful to understand what factors work to shorten the life of a bearing.
What will shorten a bearing’s life?
The causes of a shortened bearing life – or failure – are too numerous to list here. Let’s instead highlight the things permanent lubrication actively works against. As mentioned earlier, lubrication issues are the largest cause of bearing failures. There are multiple reasons lubrication might be the cause of failure, though. Contamination from excessively dirty applications and seal deformation, which creates a pathway for contaminants and moisture, will also shorten a bearings life.
Generally, bearings require a ⅓ grease fill for proper operation. Because seals obstruct our view, it is impossible to determine how much grease is in a bearing at any given moment. Too much grease and the rolling elements have to fight through it – called “churning” – causing increased heat, efficiency loss, and grease degradation. Too little grease and the rolling elements won’t have enough oil to protect them.
Incompatibility between different greases can cause irreversible issues. When incompatible greases mix within a bearing, problems such as “oil bleed” occur, or the creation of hard salts, which form when thickeners conflict with one another. By lubricating a bearing for life, solid lubrication eliminates this issue outright.
Even the dirtiest application sites need bearings. There are times when it’s impossible to keep bearings from being inundated with contamination. Inevitably something will work its way into the interior of the bearing. Once the rolling element rolls over even the smallest particle, damage will occur. This damage will repeat, compounding, and severely affect the rolling element. This is a path to failure.
Is this avoidable? YES! There are solutions available that effectively negate all of these issues.
How can permanent lubrication help?
Permanent lubrication drastically reduces lubrication-related issues from happening, right out of the box. The bearing is lubricated for life. Interactions with the bearing are limited to installation and replacement.
Aside from lubrication, the polymer itself is beneficial to bearing life. As mentioned earlier, it is nearly impossible to eliminate the ingress of contaminants. The polymer is a solid that fills the bearing cavity, abutting the inside of the seal. If something does manage to work its way inside the bearing, the polymer arrests its progress immediately.
There is no fear of mixing two incompatible greases. No reason to worry about the grease quantity within a bearing, or what the condition of the grease might be. The oil-loss from permanent lubrication is negligible compared to oil bleed from a greased bearing. Permanent lubrication removes bearing maintenance entirely. Set it and forget it.
Once something makes contact with the polymer, it will have difficulty getting any nearer the rolling elements. This is vastly different than standard lubrication, which circulates contaminants with the grease during operation. The polymer essentially acts as an ancillary seal.
While not a common occurrence, there are applications that require washdowns, typically found in food-grade or extremely dirty environments. Occasionally washdowns can damage or deform a seal, allowing for the ingress of water. Once a seal is damaged, this is an open invitation to both contaminant ingress, grease loss, and the intrusion of water. The structure of the solid lubrication polymer mitigates the possibility of having the seal lose its integrity.
A greaseless bearing provides more than reliable lubrication.
Permanent lubrication in a bearing is a comprehensive solution. Reliable and consistent lubrication is just the beginning. An added layer of protection to the rolling elements is an inherent benefit. But the peace of mind and time savings that come along with this technology are highly beneficial. Longer lasting bearings mean increased productivity.