Characterizing Foam Behavior with the Lubricating Oils Foaming Characteristics Tester

Characterizing Foam Behavior with the Lubricating Oils Foaming Characteristics Tester

Introduction
Foaming in lubricants can impair heat transfer, reduce film strength, and lead to cavitation in pumps. Changsha Friend’s Lubricating Oils Foaming Characteristics Tester systematically evaluates both foam tendency and stability at multiple temperatures, guiding anti‑foam additive optimization.

Testing Principle
Per ASTM D892 or ISO 6247, oil samples are conditioned at 24 °C and 93.5 °C in graduated cylinders. Air is sparged at a constant rate (10 mL/min) for 5 minutes; foam height is recorded immediately and after a 10‑minute collapse period. The instrument’s dual‐bath design and metered airflow ensure reproducible foaming indices.

Technical Design Features

• Dual‑Temperature Baths: Maintain test points at 24 °C ±0.5 °C and 93.5 °C ±0.5 °C.

• Electronic Mass‑Flow Controller: Provides stable, repeatable air injection.

• Digital Height Measurement: Ultrasonic or optical sensors detect foam column height with ±1 mm accuracy.

• Automated Timing and Logging: Measures foam and collapse volumes, then generates index reports.

Industry Applications

• Gear and Turbine Oils: Optimize antifoam additives to prevent lubrication failure.

• Hydraulic Fluids: Screen formulations for cavitation resistance.

• Industrial Coolants: Evaluate defoamer performance in metalworking fluids.

Best Practices

1. Sample Degassing: Remove pre‑existing air by vacuum or gentle heating.

2. Cylinder Care: Clean and dry cylinders thoroughly between runs.

3. Air Supply Quality: Use oil‑ and moisture‑free compressed air to prevent contamination.

4. Replicate Testing: Perform at least two runs per sample and average results for reliability.