How Frequently Should Samples Be Taken?

Sampling should commence from the initial commissioning of the equipment wherever possible. Power generation, steel mills, paper mills often have circulating systems which may have an initial charge of may thousands of litres of lubricant or hydraulic fluid which can last for five, ten or more years. It is therefore important that the system is clean and that the fluid is used properly from the time of installation.

Frequency of sampling is dependent on the operating critically of the machine. In the first months of operation the monitoring interval should be short so that a database of information be created for each machine component. A typical sampling frequency for general industrial equipment should be every month for the first six months, then reviewed and adjusted. A sampling schedule for mobile plant equipment would be every 250 hours of operation, whereas transport, such as buses and lorries would be sampled at 2500Km/s intervals with adjustments made to suit the duty cycles.