Smooth operators

Manufacturing downtime costs money. Whether it occurs in a small, discrete environment or a huge process plant, spending money fixing problems rather than making things to sell is bad for business. Do it too much and you could even see your company fall to more efficient operations.

No wonder then, that condition monitoring — the process of analysing physical changes in equipment to identify an increased probability of failure — is becoming more widespread.

By far the most popular method is analysing increased vibrations or irregular vibration patterns emanating from part of the equipment, using a vibration sensor or accelerometer, or an array of these devices.

This is particularly useful for checking bearings, where the analysis can be a key indicator of developing problems. Vibration and noise are produced by imperfections in the [ideally smooth] surfaces of roller bearings used in common engineering components such as gearboxes and other rotating plant, and increased noise and vibration are usually signs of impending failure. Failure can be caused by a number of factors such as bearing misalignment, bad lubrication, surface defects or poor fitting. It is preceded by vibration at a characteristic frequency which, if isolated from all the other sources of vibration in a working plant, can give a good indication of bearing condition.