Sampling & Trend Analysis
The first step in any fluid analysis program is obtaining a sample. Regular sampling and trend analysis (monitoring test data over an extended period of time) provides the information you need to continually maximize asset reliability and increase profits. Comparing a component's most recent samples to its historical data is instrumental in identifying trends that can indicate potential problems or possible failure.
Fluid analysis is most effective when samples are representative of typical operating conditions. Dirt, system debris, water and light fuels tend to separate from lubricants and coolants when system temperatures cool. For optimum results:
- Take samples while systems are operating under normal conditions or immediately after shutdown while they are still at operating temperature.
- Take samples at regularly scheduled intervals.
- Take samples from the same sampling point each time.
Suggested Sampling Intervals and Methods
Although an equipment manufacturer's recommendations provide a good starting point for developing preventative maintenance practices, sampling intervals can easily vary. A piece of equipment's importance to production is a major consideration for determining sampling frequency, as are environmental factors such as hot, dirty operating conditions, short trips with heavy loads and excessive idle times. See the chart below for suggested sampling intervals and methods.*