Oil analysis is a proactive approach to monitor your machines whilst in operation. As important as a blood sample is to the human body, so is oil analysis to your machines. It is vitally important to know the state of your machine and equipment. History and trend can eliminate possible component/equipment failures.
Lubrication, Hydraulic, Gear and Engine Oil
- Wear Metals
- Water/moisture content
- Cleanliness levels
- Particle Counts
- Additive packages
Benefits of Oil Condition Monitoring
- Identify potential equipment problems/failures
- Identify when wear and tear are taking place
- Provide documentation/history for warranty claims
- Ensuring the additive package are within specification
- Identify Particle and Water contaminants
Transformer Oil Tests
- Furanic analysis
- Polychlorinated Biphenyl (PCB) analysis
- Dissolved gas analysis (DGA)
- Corrosive Sulphur
- Moisture content
- Total acid number (TAN)
- Dielectric strength
Furanics are degradation products of the insulation paper found in transformers. Analysing furanics is important in predicting the degradation of insulating paper.
The following will destroy insulation paper:
- Water (moisture)
- Oil oxidation
Poly-chlorinated Biphenyl (PCB) analysis: were realised in the 1970’s during the oil crisis to bulk up the transformer oils. Due to the high toxicity of PCB’s, it is now legislation to know the PCB content of your transformer oil.
Dissolved Gas Analysis (DGA): Dissolved gases in transformer oils are inherent gases and gases that form due to the breakdown of paper or oil under stress or degradation. With regular testing, the following problems can be detected months in advance.
- Loose connections
- Breakdown in cellulose
- Partial discharge
Corrosive sulphur forms acidic conditions in transformers. This is a vital test as DGA, MAD and Furanic tests may indicate normal operation even when failure is imminent. If corrosive sulphur is found, the oil needs to be replaced.
Moisture analysis is important to determine the moisture content in transformer oil in order to:
- Determine if there are any leaks in the transformer
- An increase in moisture indicates insulating paper degradation
- Determine if a decrease in insulating strength is due to high water content in the transformer oil
- Total Acid Number (TAN) is the quantity of base (mg of KOH) that is required to neutralise acid constituents in 1g of a sample. An increase in acid indicates that sludge formation is beginning to occur or is occurring.
Dielectric Strength is the voltage at which breakdown of the oil occurs. Insulating power decreases as the number of contaminants in the transformer oil increases so the insulating quality of the oil can be predicted.
- Distillation (ASTM D86)
- Density at 20°C (ASTM D7042)
- Viscosity at 40°C (ASTM D7042)
- Flashpoint (ASTM D93)
- Total contamination (IP440)
- Water content (ASTM D6304)
- Sulphur content (ASTM D4294)
- Cetane index (ASTM D976)
- ISO 4406 Particle count (ASTM D7619)