I. Basic Oil Inspection
1. Fluid Level and Condition
Park the roller on level ground. Turn off the engine and check the dipstick level (it must be between the upper and lower scale lines) for 15 minutes.
Observe the oil color: Normally, it is light yellow or brown. If it is black, turbid, or contains metal shavings, replace it immediately.
2. Odor and Texture
Normal oil should have no pungent odor. A burnt or sour odor indicates deterioration.
Dip your finger in a small amount of oil; it should be thick and smooth. If it is thin or grainy, it is unqualified.
II. Key Performance Tests
1. Viscosity Test
Hydraulic oil/gear oil must meet ISO viscosity standards (e.g., grades 32/46/68 are commonly used for hydraulic oil).
Use a viscometer to measure the kinematic viscosity at high temperature (100°C). If the deviation exceeds ±10%, the oil must be replaced. 2. Contamination Analysis
Check the moisture content (should be ≤0.05%) and mechanical impurities (visual inspection indicates no suspended matter).
For professional testing, refer to the oil contamination level (e.g., NAS 1638).
III. System Function Verification
1. Pressure Test
The hydraulic system's idle pressure should be ≥0.1 MPa, and 0.2-0.5 MPa at high speed.
Abnormal oil pressure gauge readings or instrument alarms require troubleshooting the oil pump/filter.
2. Demulsibility
After mixing hydraulic oil and water, allow the oil to separate for ≤5 minutes (standard for No. 8 hydraulic transmission oil).
IV. Professional Testing Recommendations
Laboratory Testing: Submit oil samples regularly for analysis of indicators such as acid value, flash point (≥180°C), and oxidation stability.
Oil Purifier Treatment: If contamination is detected, use a vacuum oil purifier to remove moisture and impurities.
