Impact of top up oil on foaming

Jan 15, 2013 | Eka Kamila., oil analysis, Techenomics

The following post is a precise of a research project conducted by Techenomics Indonesia’s chief chemist. A number of our customers regularly filter their hydraulic oil to extend lubricant life.

There is always a concern that aggressive filtration may affect the foaming tendencies. This work indicated that by regular top of with new oil can greatly reduce any foaming tendencies.

“Foam is a collection of small bubbles of air that accumulate on or near the surface of the fluid. Foam is an efficient thermal insulator, so the temperature of the oil can become difficult to control. The presence of air bubbles in the fluid can lead excessive oxidation, cavitation, the reduction of lubricating properties of the oil and hydraulics system failure.

The causes of  foaming are many, the most common include:

•                Water contamination

•                Solids contamination

•                Mechanical issues (causing excessive aeration of the fluid)

•                Cross contamination of the fluid with the wrong lubricant

•                Contamination of the fluid with grease

•               Too much antifoam additive, either by incorrect formulation or by incorrect reconstruction of the additive package

With the addition of top up, levels of foaming in the lubricant can be controlled, so as to minimize the volume of oil consumption and ultimately to reduce the cost of care units.

The result is expected to provide information for the reader to reconstruct the lubricant so as to provide good impact on engine maintenance.

Graph 1 : Top up effect against foaming tendency

Graph 2 : Top up effect against TAN value

Graph 3 : Top up effect against visco 1000C

Graph 4 : Top Up effect against Visco 400C

Graph 5 : Top Up effect against Millipore test for insoluble

Addition of top up 20%, can reduce the foaming tendency to 87.5% (normal limit). And future results of this study and subsequent research, will be grouped according to :

  1. Unit
  2. Oil type
  3. Oil hours
  4. Normal operation condition

This grouping is done to classify the top up so far the results vary, most likely be caused by :

  1. Different units of large capacity and small capacity, which affects the load.
  2. Type of oil, the additive composition of the various brands is very influential on the oil resistance.
  3. Oils hours, use of long-terms and short term would have caused a different impact on the performance of existing additive in oil.
  4. Abnormal operation conditions, over-heating, over-load, seal leaks and other”

Eka Kamila, Chief Chemist, Techenomics Indonesia.

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