BACK PAGE BASICS
Hydrolysis within lubricating oils can cause a variety of problems. Not only can it affect the oil's physical properties (viscosity,
color, etc.), but it can also change the chemical properties. One of
the most common effects of hydrolysis is the formation of acids,
predominately carboxylic acids. These acids are weak in comparison to sulfuric acids, but they can lead to machine damage. The
acids will appear on a Fourier transform infrared (FTIR) spectroscopy scan and can be monitored by routine oil analysis.
55%
of lubrication professionals
have seen the effects of
hydrolysis in machines at their
plant, based on a recent survey
at machinerylubrication.com
May - June 2013
| www.machinerylubrication.com
1. Restrict its ingression
2. Recognize its presence
3. Analyze its state and concentration
As the hydrolysis process continues, the oil's viscosity will begin
to fall. This decrease in viscosity poses a very real threat to a
machine's health. As the viscosity drops, the fluid's load-carrying
capacity will also be diminished, resulting in the machine operating
in a boundary lubrication regime and more pronounced wear.
By being proactive and preventing water ingression into your
oils, you can mitigate the process of hydrolysis. Vigilance in monitoring the oil's water content and acid number along with FTIR will
serve as the best weapons for determining if hydrolysis is occurring.
Keeping your oil dry will save you the devastating effects of this
chemical process.
56 |
4 Ways to Mitigate
Water Contamination
4. Remove it quickly
References
Forest, M. and Araud, C. "A New Approach for Oil Formulations."
Papay, Andrew G., and Harstick, Christian S. "Petroleum-Based Industrial Hydraulic Oils - Present and Future Developments." Lubrication
Engineering, Jan. 1975: 6-15.
Kajdas, Czeslaw. "Hydrolysis."
"Standard Test Method for Hydrolytic Stability of Hydraulic Fluids
(Beverage Bottle Method)," ASTM Standards 2012.
About the Author
Wes Cash is a technical consultant with Noria Corporation. He is a
mechanical engineer who holds a Machine Lubrication Technician (MLT)
Level II certification and a Machine Lubricant Analyst (MLA) Level I certification through the International Council for Machinery Lubrication
(ICML). Contact Wes at wcash@noria.com.
