Judging the quality of anti-wear hydraulic oil requires a comprehensive evaluation from multiple dimensions, including appearance, physicochemical properties, and professional testing indicators. The following are specific methods for judgment:
Preliminary Judgment Through Appearance and Sensory Observation (Simple Method)
These methods are suitable for quick on-site identification, but are for reference only and cannot replace professional testing.
Color and Transparency: High-quality anti-wear hydraulic oil is usually clear and transparent, a light yellow or pale amber color, without suspended matter, sediment, or turbidity. If the oil is black, dark, or milky white and cloudy, it may have oxidized or been contaminated with water.
Odor: Normal hydraulic oil has a light odor. If you smell a pungent, burnt, or fuel-like odor, it indicates that the oil has been oxidized at high temperatures or has been mixed with impurities such as diesel fuel.
Viscosity and Hand Feel Test: You can use the "hand-rubbing method" to roughly compare viscosity: Take a small amount of oil and rub it between your fingers. High-quality oil should feel lubricating, with moderate fluidity, neither too astringent nor too thin.
Foam Observation: After vigorous shaking, the foam produced by high-quality oil should dissipate quickly. If the foam is abundant and persistent, it indicates that the antifoaming agent has failed or the oil has deteriorated.
Moisture Detection (Simplified Method)
Cracking Test: Drop the oil onto a hot iron plate (approximately 110°C). If a cracking sound is heard, it indicates that the water content exceeds the standard (>0.2%).
Test Tube Heating Method: Place the oil sample in a test tube and heat it. If bubbles are produced or water droplets condense on the tube wall, it indicates water contamination.
