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A Guide to Bearing Lubricants

Release time : 2023-03-28 13:11:35

Why Bearing Lubrication is Important

Effective bearing lubrication is crucial for the optimal performance and longevity of bearings. It's widely accepted in the industry that 80% of bearing failures can be traced back to bearing lubrication issues. Proper bearing lubrication can help create a protective layer between the surfaces of the bearing, reducing the effects of corrosion and wear caused by contaminants. Furthermore, effective bearing lubrication can help assist in dissipating heat, which is essential in maintaining the bearing's overall performance and avoiding costly downtime. 

Neglecting to implement proper bearing lubrication practices can result in increased friction, wear, and ultimately, premature failure of the bearings. To ensure that your equipment operates at its best, it is important to have a good understanding of bearing lubrication and its effect on bearing performance.


Factors Affecting Bearing Lubrication

  • Speed: High speed causes more friction and heat, leading to a need for higher viscosity lubricants.

  • Temperature: High temperatures can cause lubricant breakdown and evaporation, leading to poor lubrication. Low temperatures can cause thickening of the lubricant, which can cause drag and difficulty in starting up.

  • Load: Higher loads increase the pressure on the lubricant film, which requires a higher viscosity lubricant to maintain a sufficient film thickness.

  • Contamination: Particles and debris can cause abrasion and reduce the effectiveness of the lubricant.

  • Viscosity: The viscosity of the lubricant is important to maintain the correct thickness of the lubricant film under varying load and temperature conditions.

  • Type of lubricant: Different types of lubricants (e.g., oil, grease, solid lubricants) have different properties and are better suited for different applications.


Types of Bearing Lubricants

Maximizing bearing life and minimizing maintenance costs begins with selecting the right type of bearing lubricant. With options like oil, grease, solid lubricants as well as drying lubrication on the market, it's crucial to match the lubricant type to the bearing type. Choosing the wrong lubricant can result in inadequate bearing lubrication as well as reduced bearing life. Don't risk costly downtime – prioritize proper lubrication selection for your bearings.


  • Oil Bearing Lubricants

Looking for a bearing lubricant with low viscosity and high fluidity? Oil lubricants may be just what you need. Generally thinner than their grease counterparts, oil lubricants are ideal for high-speed applications with low starting and running torque. To find the perfect oil lubricant for your needs, take a look at our chart below, which details different types of oil lubricants, their operating mechanisms, and ideal applications. 

Oil Lubricant

Oil Lubricant for Bearing Lubrication

  • Grease Bearing Lubricants

Are you looking for a bearing lubricant that offers superior adhesion, longer life, and better corrosion resistance than oil-based lubricants? Look no further than grease lubricants! The Grease lubricant is the choice for 80% to 90% of bearings. It can provide lasting protection and improved performance in applications requiring higher viscosity and tackiness. Pre-lubricated without the need for an external system, grease lubricants make maintenance easier and offer longer bearing life, so you can enjoy reliable performance for years to come. Explore our diagram below to learn more about the grease lubricants as well as how to use them. 

Grease Lubricant

Grease Lubricant for Bearing Lubrication

  • Solid Bearing Lubricants

If you find yourself facing extreme operating conditions, such as high temperatures, radiation exposure or vacuum environments, traditional bearing lubricants may not be up to the task. This is where solid lubricants truly shine! With their unique properties, solid lubricants are often the preferred option when all other choices have been exhausted.


  • Drying Bearing Lubricants

In addition to the above methods, drying lubrication can be used as a secondary means of bearing lubricating in some cases. When it comes to selecting the right bearing lubricants for your specific needs, it can be challenging to navigate so many brands and specifications. That's why it's essential to consult a reliable resource like Ball Bearing Lubrication. This expert guidance can help you make good decisions about bearing lubrication, so you can optimize the performance of your bearings.

Selecting the right bearing lubricant is undoubtedly crucial for bearing performance, but it's only one piece of the puzzle. To truly optimize your bearing life and reliability, it's essential to pay close attention to the technical aspects of bearing lubrication. This includes factors like bearing lubricant viscosity, frequency of re-lubrication, and more. 


Factors to Consider when Choosing the Best Lubricant for Bearings

Factors to consider when choosing the best lubricant for bearings

Factors to consider when choosing the best lubricant for bearings


  • Identify the Proper Bearing Type

When it comes to bearing lubrication, it's essential to understand that different types of bearings have specific requirements. For instance, ball bearings, roller bearings, and plain bearings all have unique lubrication needs. To ensure the optimal performance and extend the life of your bearings, it's crucial to pay attention to these distinct requirements and select the right bearing lubricant and the bearing lubrication method accordingly.

  • Find the Ideal Operating Temperature Range for Your Bearings

Choosing the right bearing lubricant for your equipment is crucial for optimal performance, and one key factor is its ability to maintain its properties across various temperatures. To ensure effective bearing lubrication, it's essential to select a bearing lubricant that can withstand the minimum and maximum operating temperatures of the application. The lubricant's viscosity and the bearing design also play a key role in its ability to flow and provide adequate bearing lubrication. Consider these factors carefully to ensure that your bearings can run smoothly and last longer.

  • Calculate the Load for Your Bearings

To ensure the best results, calculate the load on the bearing and choose a lubricant with sufficient load carrying capacity. Note that certain types of bearings, such as spherical roller bearings and tapered roller bearings, require lubricants with high load carrying capacity. So, make sure to select the appropriate bearing lubricant to support your bearing's load and protect it from wear and tear.

  • Locate the Operating Speed of Your Bearings

The operating speed of the bearing will affect the lubrication requirements. High speed applications require a bearing lubricant with a low viscosity, while low speed applications require a bearing lubricant with a slightly higher viscosity. It is wise to choose a lubricant combined with the operating speed.

  • Define the Environment of Your Bearings

Choosing the right lubricant for your bearings also depends on the operating environment. Environmental factors such as dust, dirt, moisture, and chemicals can impact lubricant performance, making it essential to select a bearing lubricant that can withstand these conditions. Consider the specific application environment when choosing a lubricant that can handle the unique challenges of your bearings. For instance, an open bearing may require a different lubricant than a sealed bearing. Ensure that your bearings can run smoothly by choosing the suitable lubricant for your operating environment.
Viscosity is critical when selecting oil lubricants for bearing lubrication. It impacts the effectiveness and the durability of the bearing lubrication. Proper viscosity allows the bearing lubricant to flow, adhere to the bearing surface, and maintain a lubricating film between the bearing and its mating surfaces.

When it comes to grease lubrication, the base oil viscosity and the hardness are the key characteristics to consider. Choosing the right base oil viscosity and the hardness can help extend the bearing life, minimize the  maintenance costs, and reduce the downtime. By carefully selecting the right bearing lubricant for your equipment, you can ensure optimal bearing performance and longevity.


Ensure the Best Quantity of Bearing Lubricants

Proper lubrication is crucial for the optimal bearing performance. The right amount of the bearing lubricant, whether the oil or the grease, can directly impact the speed, the noise levels, as well as the overall efficiency. Over-lubrication can cause the excess heat buildup and under-lubrication can result in mechanical wear. To ensure uniform bearing lubrication and prevent damage to rolling elements and groove surfaces, it's important to use the correct amount of the bearing lubricant.

While the filling volume of grease lubricant for deep groove ball bearings is typically around 30% of the bearing space volume, the specific construction, internal space of the housing, and application conditions may also affect this amount. Optimal lubrication is determined by various factors, including the operating speed, the design, the space volume, and the degree of sealing or the external protection. Trust proven lubrication practices to help determine the correct amount of bearing lubricant needed for your specific application.


Improve Preparation and Run-In Before, During, and After Lubrication

For bearings that necessitate self-greasing, thorough cleaning is crucial to prevent impurities from hindering bearing performance and reducing the lubricant's efficacy. Using a non-residual solvent to clean the bearing surface is highly recommended for optimal bearing lubrication conditions.

To achieve the best possible results with bearing lubrication, it's crucial to follow the correct running-in procedures, especially when specific speed, preload, and lubricant quantities are involved. Proper running-in procedures guarantee sufficient lubricant in the groove, which in turn ensures optimal bearing lubrication and proper operation.


Avoid Common Errors of Bearing Lubrication


  • Wrong Use of Bearing Lubricant Types

Different types of bearings and the operating conditions require the specific lubricants. Non-extreme pressure (non-EP) or general purpose (GP) grease may be suitable for some applications, while the extreme pressure (EP) grease may be necessary for others.

Mixing different bearing lubricants can also lead to the ineffective lubrication films, the increased wear, and the premature failure because not all greases are compatible with each other.

  • Over-lubrication or under-lubrication

Too much or too little bearing lubrication can be damaging and lead to costly maintenance and repairs.

Over-lubrication can result in excessive temperature rise in the bearing, leading to heat generation and ultimately, bearing failure. It can also cause contamination and increased maintenance costs. On the other hand, insufficient bearing lubrication can cause excessive mechanical wear, leading to premature bearing failure.

  • Improper interval of bearing lubricant supply

Failure to lubricate bearings at the correct intervals can result in equipment failure due to lubricant loss. However, using an arbitrary time frequency for bearing lubrication can be counterproductive and lead to further issues. To ensure optimal performance and equipment reliability, bearing lubrication intervals should be based on the specific bearing type and operating conditions. Following the manufacturer's recommendations can help determine the ideal timing for bearing lubrication.

Grease feeding Interval

On the other hand, it's essential to accurately estimate the lubricant life while considering the frequency of bearing lubrication. For shielded or sealed single-row deep groove ball bearings filled with grease lubricant, the grease life can be estimated using the following formula.


Conclusion

Effective bearing lubrication is crucial for optimal performance and longevity. Use the best lubricant for bearings, determine the correct amount and timing of bearing lubrication, and follow proper bearing lubrication methods. Prioritize effective lubrication to avoid bearing problems and prolong their life.

Bore Diameter*:
mm
Outer Diameter*:
mm
n*:
min-1
Pr*:
N
Cr*:
N
T*:
°C
(For single-row deep groove ball bearings only)

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Goodenough Lu

Goodenough Lu is a mechanical engineering major with over ten years of experience in bearing applications.

He possesses a comprehensive understanding of the operational characteristics of a wide range of mechanical products such as automobiles, motorcycles, various motors, electric tools, machine tools, and processing equipment.

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