60 to 80% of bearing failures are lubrication related. Thus, identifying lubrication issues at an early stage is key to avoiding bearing failures. Many facilities still perform time-based lubrication: this means that bearings will be greased at regular time intervals.
This, however, will inevitably lead to bearings being under-lubricated or over-lubricated, since not all of them require the same amount of lubricant. One solution to avoid this problem is changing lubrication practices to condition-based lubrication. In this case bearings will be lubricated based on their condition, avoiding the mentioned under-lubrication and, particularly, the over-lubrication issues.
When it comes to condition-lubrication, ultrasound is the best technology. Since bearings suffer an increase in friction when they have too little or too much lubricant, and friction produces ultrasounds, we can then use ultrasonic inspection instruments to determine lubrication levels.
This is how lubrication monitoring with Ultrasound works:
The Grease Caddies from UE Systems are examples of instruments that can be used for ultrasound-assisted lubrication. They are effective and easy to use: set a baseline for each bearing, test routinely to note decibel increases. When a bearing reaches an 8 dB gain over baseline with no change in sound quality, it needs lubrication. When applying lubricant, stop when the dB level drops to baseline. It’s just that easy!
The Grease Caddies are developed specifically for supporting lubrication practices and they have clear advantages:
- Cost effective instrument for lubrication engineers.
- Simple to operate.
- Keeps your hands free to lubricate with the help of mounting bracket or belt holster.