One lubricating grease is a mixture composed of three main elements:
- Synthetic or mineral lubricating oil
- Thickener
- Additives
L’thickener has the task of retaining the oil and giving the lubricating grease its semi-fluid consistency, while the additives improve the performance of the lubricant. However, under conditions of prolonged rest o inadequate storage, a phenomenon known as static separation between oil and thickener. This occurs when the liquid component (the oil) separates from the structural component (the thickener), compromising the performance of the lubricating grease.
Static separation between oil and thickener: the issues
If the static separation between oil and thickener exceeds 10%, the stability of the lubricant may be compromised, causing:
- Loss of key additives
- Reducing the viscosity of thelubricating oil
- Increased wear and tear on components
- Increased operating temperature
- Increased need for maintenance
How to prevent separation between oil and thickener in lubricants
To prevent these problems, here are 7 effective strategies:
1. Choosing the right lubricant
Not all lubricating oils and greases are the same. Some contain specific additives to improve stability and reduce static separation between oil and thickener. Lubricants formulated with synthetic oils and thickeners with high stability offer greater resistance to liquid phase separation.
2. Opt for quality thickeners
The thickeners determine the stability of the lubricating grease. I lithium greases, lithium lithium complex and calcium complex have a greater ability to retain oil than other types of thickeners, providing better resistance to static separation between oil and thickener.
3. Optimize storage conditions.
A bad storage accelerates the separation of oil from lubricating greases. To minimize the problem, it is critical:
- Store lubricants in cool and dry environments.
- Avoid extreme temperatures.
Keep the container tightly closed to prevent contamination.
4. Avoiding contamination
The contamination with water, dust or other external particles alters the structure of the lubricating grease, promoting the separation of the oil. Using clean containers and protecting lubrication points reduces the risk of contamination.
5. Monitor operating conditions
The mechanical load, the pressure and high temperatures can promote static separation between oil and thickener. Periodically analyze the operating conditions of the machine and choose a Appropriate lubricant for specific needs helps keep the mixture stable.
6. Replace lubricants regularly.
Over time, lubricants degrade and lose their properties. A periodic replacement prevents the oil separation and ensures proper operation of equipment.
7. Regularly analyze the lubricant
L’analysis of lubricants allows early identification of signs of static separation or alterations in viscosity. Monitoring the stability of the lubricant allows early intervention to avoid more serious problems.
Which lubricants reduce static separation between oil and thickener
Some lubricants are particularly effective in preventing the static separation between oil and grease. These include:
Fats with high stability thickeners
- Lithium grease: excellent resistance to oil separation, ideal for applications general industrial. An example of such products are the MOLYKOTE® G-68 Plastic Gear Grease and the MOLYKOTE® PG-75 Plastislip Grease
- Lithium complex grease: high thermal stability, suitable for high temperatures and severe conditions.
- Calcium complex grease: excellent oil-holding capacity even in wet environments, water-resistant.
- Polyurea grease: excellent thermal stability and long service life.
- Lubricants and sulfonated greases: use calcium sulfonate as the main component. These lubricants are known for their properties that enable them to resist wear and corrosion, making them particularly suitable for use in high mechanical stress environments and extreme climatic conditions. An example of a product is the Condat Millenium 505/1, which offers exceptional mechanical stability in the presence of water or emulsion, excellent water resistance and a very high drop point. Also belonging to the category of sulfonated lubricants and greases are Condat Millenium 505, Petro-Canada PURITY™ FG2 Synthetic Grease, Petro-Canada PEERLESS™ LLG.
- Aluminum complex lubricants and greases.: Aluminum complex greases are known for their high thermal and mechanical stability, offering good resistance to runoff and corrosion. Examples of products are for example Condat Nutrigrease Hp, Petro-Canada PURITY™ FG00, Petro-Canada PURITY™ FG2 Extreme,
Lubricants with stabilizing additives
- Antioxidants: slow down degradation.
- Anti-wear additives: improve lubricant life and protect metal surfaces.
- Phase stabilizers: reduce oil separation, improving fat consistency.
Synthetic lubricants
- Synthetic lubricating oils such as PAO (Polyalphaolefins) and POE (Polyol esters) provide greater chemical and thermal stability, reducing oil separation. They respect these characteristics the MOLYKOTE® P-74 Assembly Paste, the Petro-Canada PURITY™ FG Synthetic Fluid 46, ( Suniso and Tecnite to put in ?)
- PTFE-based greases (Polytetrafluoroethylene) offer excellent separation resistance and reduced evaporation.
High-viscosity lubricants
The high viscosity lubricating oils and greases reduce the risk of separation, especially in applications with high loads.
Choose products to avoid static separation
The static separation between oil and thickener can impair the performance of lubricating greases, increasing wear and tear and maintenance costs. Implementing the right strategies and choosing the correct lubricant helps minimize this problem, prolonging equipment life.
To get more information on which lubricant to choose and applications to avoid the problem of static separation contact our Mascherpa experts.
