You had some questions, and we’ve got the answers. Read on to learn more about greases and its applications

What Grease is the best for Wheel Bearings?

Generally, Lithium EP2 would be used for slow moving bearings, such as passenger buses and trucks. For Higher Speed applications a Lithium Complex EP2/EP3 would be more suitable as higher temperatures would be generated in the wheel bearing. For wheel bearings which is more in contact with water, such as boat trailers, a Calcium Complex EP2 would be more suitable due to Calcium Soap having a higher resistance to water washout. This will be the general “rule of thumb” as there are formulations that can be applied by making use of the speed, bearing bore, bearing diameter and temperature for more specific applications.

What Does the Colour of a Grease mean?

It is important to note that while Users still judge greases by their appearance and colour, these factors have no real impact on the service or quality and is purely a visual factor. It is available in just about every colour, including black, white, grey, blue, red, purple, green, yellow, etc. In the majority of cases, manufacturers use colour to identify the type of grease, which is more appealing than the typical brown appearance. Generally, if it is white, it will be classified as Food Grade Grease, which is classified by NSF as a H1 Lubricant. If it is Grey or black, it will be typically identified as containing molybdenum disulphide (moly)/graphite. In most cases, wheel bearing grease will be Blue or Red.

How to determine the correct NLGI (National Lubricating Grease Institute) rating grease for an application:

Choosing the correct consistency of grease for an application is critical, because if it is too soft, it may drift away from the area that needs to be lubricated, and if it is too firm, it may not effectively lubricate the area that requires lubrication. The NLGI number is a measure of the consistency as indicated by its worked penetration value. The correct consistency is important for ensuring that the appropriate amount of lubricating oil is provided and maintained in the system for sufficient lubrication. 

The most commonly used greases, such as those used in automotive bearings, would use a lubricant that is NLGI grade 2, which has the firmness of peanut butter. NLGI Grades for greasing bearings are typically NLGI grades 1,2, or 3. NLGI greases 000-0 are classified as semi-fluids and tend to be less viscous. These grades can be beneficial in enclosed Gearboxes and Centralized Applications where the pumpability of grease through multiple small diameter lines are required. NLGI grades categorized in the 4-6 range, have a consistency like ice cream, fudge, or cheddar cheese. NLGI 4 is often used in Water Pump Applications, NLGI 5 in Overhead Conductors, and NLGI 6 in Pillow Block Applications.

What Grease is the best for Pins and Bushes?

A soap containing solids such as Molybdenum Disulphide (moly)/graphite is the preferred lubrication for Pins and Bushes Applications.  The inclusion of molybdenum Disulfide enhances load carrying performance whilst reducing friction, especially in those components where reciprocating or sliding motion is present.

Lithium Moly contains extreme pressure additives fortified with Molybdenum Disulfide (MOS2) for added protection against heavy loads and metal on metal contact. The Moly provides an additional measure of lubrication to protect metal surfaces when vibrating or oscillating because movements tend to squeeze out grease between the surface.

How to choose the correct Base Oil Viscosity for a Grease Application:

The most important property of any lubricant is viscosity. A common mistake made when selecting a grease is to confuse its consistency with the Base Oil Viscosity. Due to the majority of grease applications used on bearings, the speed of the bearing needs to be taken into account when selecting the Base Oil Viscosity. Charts are available from Lubricant Suppliers to determine the minimum Base Oil Viscosity required in the grease when the speed factor and likely operating temperature have been determined. The most common Base Oil Viscosity used for General Purpose Grease is 220 cSt.

Now that we’ve answered your questions and you know what you need, get in touch with us today so that we can provide you with the right grease suitable for your needs.