Why do bearings and drives fail, even when they are lubricated on time?
The 6 functions of a lubricant
Various studies show that 40–50% of all premature bearing failures can be directly traced back to incorrect or contaminated lubrication. Energy loss is also significant: it is estimated that around 20% of global electricity consumption is wasted due to unnecessary friction.
The reason? A lubricant has more tasks than just reducing friction. If one of these functions fails, problems will occur.
The 6 (and sometimes 7) functions
| Function | What it does | Particularly important for |
|---|---|---|
| 1. Reduce friction | Forms a film, prevents metal-to-metal contact → less heat and energy loss | All rotating components (bearings, gears, chains) |
| 2. Limit wear | Protects against peak loads, adhesive and abrasive damage | Bearings, plain bearings, chains |
| 3. Remove heat | Transfers heat away from loaded zones | Gearboxes, circulation systems |
| 4. Control contamination | Carries away dirt and moisture (oil) or encapsulates it (grease) | Bearings, open drives, chains |
| 5. Prevent corrosion/oxidation | Forms a barrier against moisture, oxygen and chemicals | Bearings in damp environments, chains, food & pharma |
| 6. Seal against ingress | Barrier against dust, dirt and moisture | Bearings, seals, outdoor equipment |
| 7. Transmit power | Transfers pressure/energy via fluid | Hydraulic systems, transmissions |
Challenges in modern lubrication
The six functions are well known, but the conditions under which they must perform have become more demanding:
- Higher loads and speeds
Compact machines with higher specific loads and temperatures make the lubricant film more vulnerable. - Stricter cleaning and hygiene requirements
Especially in food and pharma, lubricating films are increasingly exposed to frequent and aggressive cleaning. - Legislation and regulations
Substances such as PFAS, PTFE and microplastics are under growing pressure worldwide. - Poor and uncontrolled lubrication practices
Over- and under-lubrication, mixing incompatible products, or skipping lubrication points still account for many failures. - Lack of ownership for lubrication maintenance
If lubrication is seen as “just a task” rather than a critical reliability factor, problems persist. - No KPIs to steer lubrication programmes
Without clear metrics, it is impossible to understand how lubrication is managed, or to link lubrication actions directly to asset reliability.
Understanding how lubricating films behave in boundary, mixed and hydrodynamic regimes is key to tackling these challenges. Read our article on lubrication regimes.
Application in practice
How these functions manifest depends on the application:
Bearings → often sensitive to contamination and moisture. Functions 2 (limit wear), 4 (control contamination) and 6 (seal) are most critical.
Gearboxes → primarily require heat dissipation and stable viscosity. Functions 1 and 3 dominate.
Hydraulic systems → focus on transmitting power with minimal losses. Function 7 is key.
Example from practice
In a fan bearing, high operating temperatures and premature damage were traced back to two causes:
- Incorrect grease that could not withstand the load and temperature
- Poor and uncontrolled lubrication practices
The solution: a single-point lubricator filled with Interflon Grease MP2/3.
Before & after
Six months later, the bearing is still running reliably, with stable operating temperatures clearly visible in the thermographic images.
Conventional lubricants often lose effectiveness under high loads or during intensive cleaning. MicPol® technology provides stronger film strength and adhesion, supporting critical functions such as wear protection and corrosion resistance.
The right clean lubricant, in the right amount, at the right time: that is the key to success.
Conclusion
Lubricants are not a minor cost item but a determining factor for reliability and efficiency. Their functions, from reducing friction to controlling contamination, are essential for stable performance and longer component life.
As machines are required to operate more efficiently and sustainably, the demands on lubricants continue to rise. At the same time, many lubrication programmes still lack structure:
- Poor and uncontrolled practices persist
- Ownership is unclear
- No KPIs to steer lubrication programmes. Without clear metrics, it is impossible to understand how lubrication is managed, or to link actions directly to asset reliability.
These demanding conditions require more than conventional lubrication. Interflon’s MicPol® technology is designed for this purpose, strengthening the lubricant film so that critical functions remain effective, even under high loads, aggressive cleaning or extended intervals. With our PFAS-free solutions, companies can also meet future compliance and sustainability demands.
👉 Would you like to know which functions and practices are most critical in your machines? Our technical advisors can assess your lubrication programme, define the right KPIs and help secure long-term reliability.
