Too much of
a good thing

Willem Pelt, Business Development Manager, Hove

When is enough enough? A simple question, but the answer is rarely straightforward when it comes to lubricating wind turbines, port cranes, or similar heavy equipment.

Most operators and technicians are afraid of not adding enough lubrication, so they often take a better-safe-than-sorry approach and flood each lubrication point.

However, from the machine’s point of view, this is far from safe: Every year, over-lubrication costs wind farms and ports millions of dollars in repairs and downtime.

Here’s why – and how to avoid it.

The hazards of over-lubrication
One of the more well-known concerns with over-lubrication is the fact that excessive lubrication in bearings leads to higher working temperatures—simply because the machine is forced to work much harder to push through the grease. This can lead to seal damage and potential failure.

Excess grease from over-lubrication can even block bearings. This can significantly reduce the machine’s efficiency and, over time, lead to equipment damage.

A lesser-known problem with flooding lubrication points is the risk of churning.

Lubrication churning occurs when a bearing or gear is forced to churn through the lubrication. This separates the oil from the thickener, which then hardens and impedes the functions of both bearings and gears.

When it comes to bearing- or gear failures in heavy machinery, churning is one of the more common culprits.

Mitigating over-lubrication
Whether the problem appears in the shape of increased working temperature, blocking, or churning, the effects of over-lubrication can be costly in the shape of expensive repairs and downtime.

So, how can you tell if a machine is over-lubricated – before it breaks down?

This is a tricky job, as inspecting bearings is difficult without running them, removing them from housing, or using specialized equipment.

The best indication of a bearing’s condition is found by observing the machine in action and listening to its sounds.

If it makes squeaky noises when running or you observe vibrations or play in bearings, the machinery is likely to be under-lubricated.

On the other hand, if you can see a rise in temperature or grease or oil spills around bearings, you’re probably looking at an overlubricated machine.