5 Attributes to Select the Right Grease for Your Equipment Needs
Looking at these below 5 attributes for selecting the right type of lubricating grease for the equipment is crucial. Colour is definitely not one of these as there’s more to it than what meets the eye.
When it comes to grease lubricant, there is no such thing as “all-purpose” grease. Every single application requires a different type of oil and here we are discussing the 5 major attributes to look out for while choosing the lubricating grease for your equipment.
Frequently Asked Questions- Grease Lubricants
Greases comprise of various oils, thickeners & additives and in some situation solid lubrication is also added as per the requirement of applications
1 . Performance required by application
2 . Operating Conditions
3 . Equipment type and its arrangement
4 . Operating speed, temperature and load
5 . Type of lubricant based on application
6 . Sealing, mounting and dismounting
Greases are formulated to operate in a wide variety of applications. Varying types of thickeners, oils and additives are blended to produce a lubricating grease with the desired performance criteria.Not all lubricating greases can be mixed together.If two incompatible lubricating greases are blended with one another the thickeners can react chemically and turn into a hard solid with no lubricating properties.
In grease lubricated bearings, oil bleeds from the thickener onto the moving components. During use, the oil properties will fade and need to be replenished. This is referred to as the lubricating grease service life (GSL).
Lubricants have no change in consistency or appearance if kept for shelf life as mentioned in Material Safety Data Sheet. Shelf life may be longer or shorter depending upon the storage conditions.
No. If we scoop out the grease from the middle of the drum, there is very high possibility that oil will get accumulated in the middle (possibility due to oil bleeding properties of a grease). One should always remove lubricating lubricating grease from all sides so that there is no accumulation of oil in the middle.
Color of any grease lubricant is for visual identification it can no way related to performance or possible contamination of lubricating grease. Change of lubricating grease should be based on physio-chemical properties and not necessarily visual changes.
Grease is generally applied manually or with lubricating grease gun between the ball/rolling element forcing it into and around the ball raceway interface. It gets evenly distributed within the bearing while rotation of bearing.
So the five attributes are summed up as follows
1. NLGI Rating
The National Lubrication Grease Institute Rating is a criterion that determines the consistency of lubricating grease, the higher the rating, the thicker is the grease.
The number is usually determined by the ratio of oil to the thickener in the grease. Low rated grease is helpful in cold climates as pumping is made easier whereas higher rated ones are more stable in hot climates.
There are several additives in lubricating oil, out of which, the thickener is the most important one.
It acts as a ‘soap sponge’ that maintains the consistency of the oil and holds it in its place and then spreads across to lubricate all the components.
Different types of grease are used for different thickening agents, and they may not be compatible with each other.
4. Dropping Point
The dropping point is the operating temperature at which grease is liquefied and does not perform.
It is thus important to make use of grease that remains constant within the maximum operating temperature of the application.
5. EP Additives
EP which stands for Extreme Pressure is a tag that is labelled under a certain category of lubricating greases.
These are common for various applications except electric motor bearings where it can cause corrosion if there is over greasing on part of motor windings.