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Background & Properties
Industry Specifications
Hydraulic Fluids
July 2017
Thermal Stability: Cincinnati Milacron
This test evaluates whether an oil will cause a reaction to steel and copper components. Run for 168 hours at 275°F.
Test Criteria P-68, P-69 HF-O
and P-70
Viscosity change, (%), max 5
Neutralization number, (%), max ±50
Sludge (mg/100 ml), max 25 100
Copper wt loss (mg), max 10
Copper rod appearance 5 Report
Iron rod appearance No discoloration
1000-h Sludge (ASTM D 4310)
This test measures the build-up of sludge and increase of iron and copper particulate in the oil.
Test Criteria Denison HF-O HF-1 HF-2
TAN (mg KOH), max 1.0 .2 1.0
Insoluble Sludge, mg max 100 100 400
Total Cooper, mg max 200 - 200
Total Iron, mg max 50 - 100
TAN (ASTM D 974-07)
Standard Test Method for Acid and Base Number by Color-Indicator Titration
Importance of Wear and Load Tests
Load performance and wear protection are crucial components when selecting a hydraulic fluid. Hydraulic fluids are
designed to handle important shock loads and other various types of loads during operation. The ability to prevent
metal to metal contact also results in lowering component wear, such as in hydraulic pumps. Proper viscosities and
excellent anti-wear additives play a pivotal in protecting against wear.
Types of Wear and Load Tests include:
Vickers 35VQ-25 Vane Pump Test
This test measures wear to the cam ring and the vane pump. It is run for three, 50-hour segments at 200°F, 3,000 psi
and 2400 rpm.
Test Criteria
Ring 75-mg max
Vane 15 mg max
Total 90 mg max
C 3