Properly Lube Specialty Bearings

Bearing and lubricant selection may provide the increased efficiency needed to advance plant sustainability.

By Chris Johnson, SMB Bearings

According to the International Energy Agency (IEA), the industrial sector is responsible for a staggering 37% of global CO2 emissions, making it the largest emitting sector worldwide. Industrial machinery has been identified as a significant contributor, placing an urgent onus on manufacturers to reduce the environmental impact of their equipment and find sustainable solutions to reduce their carbon footprint. 

The IEA’s report underlines how inefficient machinery contributes directly to excessive energy waste and higher emissions. What steps can manufacturers take to make their machinery more efficient? One answer lies in properly lubricated specialty bearings, which can help reduce energy consumption and contribute manufacturers meeting environmental responsibilities. 

Specialty bearings

According to a study conducted by the U.S. Department of Energy, reported by Reuters, it’s estimated that approximately a third of industrial energy usage in motor-driven systems is consumed by bearing friction. This includes rolling-element and plain bearings. Specialty bearings can reduce these friction losses but they must be the right bearings. The reason most standard bearings underperform is that the material from which the are made is not chosen in accordance with the application and load. 

A better option is to use high-performance bearings that are specifically engineered to reduce friction. By making the right choice of plastic, ceramic, or steel bearing in the appropriate size for an application, it’s possible to enhance the overall efficiency of industrial processes. 

Specialty bearings are designed for unique environments and specific applications, including to optimize efficiency, reduce maintenance, and enhance overall performance, making them indispensable where standard bearings fall short. Sectors such as aerospace, automotive, medical equipment, and manufacturing rely on these bearings to excel at high temperatures, in corrosive environments, under heavy loads, and at high speeds. These bearings incorporate innovative technologies that dampen noise and minimize vibration, creating a more harmonious and environmentally friendly operating environment.  

Types of bearings

In aerospace, ceramic and hybrid specialty bearings thrive due to their lightness, durability, and resistance to high temperatures. Automotive applications benefit from polymer and magnetic bearings, addressing friction reduction, energy efficiency, and noise suppression. 

Medical equipment relies on precision ceramic and stainless-steel bearings for smooth operation and sterility. Manufacturing, characterized by heavy loads and high speeds, benefits from hybrid and ceramic bearings, excelling in performance and longevity. Each specialty-bearing type aligns with specific sector needs, enhancing efficiency and sustainability in their respective applications.

Non-steel bearings, often made of materials such as ceramics, typically have lower friction, reducing energy consumption and improving operational efficiency. These materials can also be more resistant to corrosion and wear, extending the bearing’s lifespan and reducing maintenance needs. Additionally, their use aligns with sustainability goals due to reduced reliance on non-renewable resources and the potential for longer-lasting, energy-efficient machinery, contributing to a greener and more environmentally friendly operation.

When selecting a specialty bearing, key specifications to consider include load capacity, speed rating, operating temperature range, corrosion resistance, precision level, lubrication requirements, and compatibility with a specific application’s environment. Material composition and construction design are crucial. Additionally, assessing factors such as noise, vibration, and maintenance needs is essential. Manufacturers should conduct feasibility tests if possible.

Properly selected and maintained bearings in rotating assets can play a significant role in improving plant efficiency and sustainability.

Lubrication requirements 

Specialty bearings can alter lubrication requirements due to their unique characteristics. Some specialty bearings incorporate self-lubricating materials, reducing or eliminating the need for external lubrication. Others might demand specific lubricants to suit their materials or operating conditions, enhancing performance and durability. Additionally, factors including operating temperature, speed, and load can influence lubrication intervals and types. 

In most scenarios, optimal bearing performance necessitates smooth rotation with minimal frictional torque and heat emission. Mineral or synthetic lubricants, catering to general and high-speed functions, are predominantly favored. While oils facilitate high speeds with negligible resistance, their transient nature limits their utility. Instruments with slower or intermittent rotations typically rely on oil lubrication. Conversely, for heightened velocities, unless a consistent oil-application method, such as spray or bath, is available, a grease-lubricated bearing is recommended.

Several bearing greases exist, including finely filtered variants for low-noise applications, water and chemical-resistant options, temperature-adaptable selections, and robust high-load varieties. Eco-friendly lubricants, such as LGGB 2, are biodegradable, low-toxicity greases that meet engineering demands while being environmentally safe. These lubricants are based on synthetic ester oil and biodegradable ingredients, reducing harm and contamination.

Remember, it’s not solely the lubricant type that influences outcomes, but also the quantity applied. Excessive grease can be detrimental, increasing rolling resistance (frictional torque). This amplifies the risk of overheating, which is detrimental to bearings. Typically, a standard fill of 25% to 35% of internal space suffices.

Engineering analysis 

Swapping specialty bearings into conventional assets isn’t always straightforward. Specialty bearings are engineered for specific conditions, differing in size, material, and design from conventional versions. Their unique properties might not align with existing asset dimensions or operating parameters, potentially leading to suboptimal performance or failure. Compatibility issues, load discrepancies, and fitting challenges can arise. 

Before attempting a swap, thorough engineering analysis is crucial to ensure the new bearing fits seamlessly within the asset’s design and can withstand its intended operational demands, thereby preventing unexpected issues and maintaining asset reliability.

Specialty bearings also depend on precise manufacturing techniques. Tight tolerances and high-quality control during the production process must ensure that the bearings are precisely crafted, reducing inconsistencies and irregularities that can lead to increased friction. The support of a specialist bearing supplier is crucial to ensure the correct type of bearing is matched to a given environment or application. 

This advice can also help address the pressing issue of the environmental impact of industrial machinery, which demands immediate attention. Specialty bearings offer a promising solution to this challenge by enabling the use of eco-friendly lubricants, reducing energy consumption, and minimizing noise and vibration. EP

Chris Johnson is Managing Director at SMB Bearings, Oxfordshire, UK (smbbearings.com). The company provides bearing and lubrication solutions.