Understanding Grease Bleeding (Grease Separation)
Grease bleeding is a kind of oil separation and an expression used to refer to grease that has released oil during storage. In steady conditions, oil bleeding is identified by the presence of small pools of oil, particularly when the grease surface is not flat or has a scoop removed out of it. In working conditions, it is distinguished by oil leaking from a lubricated component due to extreme pressure or heavily loaded condition.
Knowing more about grease & oil seperation
Separation of oil is a natural behaviour of soap thickened greases. This property is required for the grease to lubricate properly in the load zone, such as with a rolling element of the bearing. When the heavy load “squeezes” the grease, it releases oil from it which lubricates the component. Additives may help to form a better lubricating film yet in certain cases, the thickener can contribute to lubrication as well.
The separation of oil shall vary based on the storage time and temperature. The higher the storage temperature, the more are chances the oil will be released. Similarly, the lower the base oil viscosity, the more oil separation shall occur. Studies have also suggested that when the grease is in storage conditions, it is normal to have oil separation of up to 5 percent of the volume.
Grease Bleeding Property
Grease bleeding is a natural property, it needs to be minimized during storage to ensure the lubricant is in the best condition when needed. Although bleeding will not be eliminated completely, little free oil can always be seen over the surface of the grease.
If grease bleeding is seen during storage conditions, you can simply stir or mix the oil to reincorporate it into the grease prior to use. Blend the oil into the top 2 inches of the grease using a clean spatula and in a clean space to avoid contaminants, which could damage the lubricated components.
Guidelines for Grease Storage
New grease cartridges, tubes or containers should be stored upright in the vertical position with the plastic cap up at all the time. This helps to prevent oil from leaking out of the vessel.
If the cartridge is placed in a grease gun, When not in use the gun should be depressurized and stored in a horizontal position in a clean, cool and dry area. This stops oil from bleeding to one end of the grease gun by keeping the oil level maintained and grease consistent throughout the length of the tube/cartridge.
When the lubricating grease is in use, and some oil leaks out of the equipment, the remaining grease in the cavity get hardened. In this situation, it becomes important to regrease the component more frequently, purge the excess grease, and do not over-lubricate. After all, the correct grease must always be verified before being used for the application.
The Correct grease is recommended by a trusted Lubrication partner, who studies the Equipment and provides the optimum lubricating solution which results in an increase in the mechanical efficiency and thus the overall efficiency of the unit.
MOSIL Lubricants is one such Lubrication partner with the leading clients over pan India and across the globe. A lubricating solution is always offered after proper study of the Equipment and its working conditions.