How to achieve the three Rs with bearings
Alan Stewart of Rubix Bearing Distributor writes
Used in every conceivable manufacturing application, bearings keep production running smoothly by transferring motion and transmitting forces. Individual bearings consume relatively little power, but since they are widely used and are also one of the most frequently replaced components, the durability of the bearings you use is important. By applying the 3 Rs of the waste hierarchy – Reduce, Reuse, Recycle – to this category of components, we can make a real difference.
Is it possible to reduce the number of bearings used? Well, you can’t just not use a bearing where it’s needed, but by extending their life, you can reduce the total number of bearings used over the life of this machine.
To ensure longevity, select the correct bearing for the task at hand. There is an incredibly wide range to choose from, many of which have been designed for specific applications and industries. In the food industry, for example, specialized commercial fryer bearing units have been designed to allow hot cooking oil inside the fryer to enter the bearing and act as a lubricant. A completely different sector, but one which also presents difficult operating conditions for bearings, is wind energy. Here, a series of specialist bearings are available, including SKF black oxide bearings which provide wind turbines with better corrosion protection, better resistance against smearing, improved performance under low lubrication conditions, limited risk of friction and reduced risk of damage from aggressive oil. additives. It is important to do your homework or seek advice on which bearing is best for your specific needs.
Not only must the bearing be the right type, but it must also be of good quality. Going for a low-cost, unrecognizable brand not only risks premature failure and costly downtime, but it can also lose performance over time, which almost always results in wasted power, as most systems continue to draw energy despite the drop or lack of production. Every second of lost production is wasted energy and impacts a day’s production goals.
Ensuring that the product is installed correctly also has a role to play. Misalignment can lead to friction and vibration which can significantly increase energy consumption, as well as the risk of premature failures. Although tools to easily and accurately align bearings are readily available, designing machines with bearings that do not require realignment may be a safer option. SKF Cooper split spherical roller bearings, for example, do not require disassembly of the drive coupling or cantilever drive to replace the bearing; these types of bearings are easily and safely replaced on site, for maximum convenience.
Reducing the use of water and detergent in washes – a particular problem for the pharmaceutical and food sectors – is a major challenge. In addition, the waste water from this cleaning is often contaminated with excess bearing grease. This can be reduced by using sealed bearings without relubrication such as SKF’s Food Line Ball Bearing Units – Blue Line, which require 33% less heated water for cleaning compared to open bearing units. Plus, there’s no lubricant to contaminate the waste water, or cleaning rags or paper towels to throw away.
Reduce the amount of lubrication you use by using sealed bearings without relubrication. There are plenty to choose from, but if you’re considering equipment that will be used in very demanding sites, such as mines and quarries, you really need to consider something like SKF’s three-barrier solution. It consists of a bearing housing – with S labyrinth seals, a lubricant as a barrier against contamination and a sealed spherical roller bearing. These three barriers protect the bearing from contaminants, extending bearing life an average of three times longer than standard open bearings.
Sealed bearings also help to reduce the use of lubrication. Alternatively, automated lubrication systems can be installed to ensure that the correct amount of lubrication is applied, reducing waste and removing the reliance on staff to undertake this task manually. Designed to lubricate individual machines or complete installations, automatic lubrication systems deliver precise amounts of lubricant at the correct intervals to all required points, minimizing friction and wear and maximizing bearing and machine life. Not only is the impact on the environment reduced, but savings of up to 50% on lubricant costs can also be achieved through precise synchronization and metering of lubricants.
When it comes to reuse, you may be surprised to learn that bearings can be remanufactured, which can significantly extend bearing life, as well as reduce costs and lead times. A wide variety of bearing types can be remanufactured, including support bearings, caster bearings, tall bearings, slewing bearings, and housings. Remanufacturing bearings can significantly reduce carbon emissions, consuming around 10% of the energy needed to manufacture a new bearing. By extending bearing service life, remanufacturing avoids component scrap and waste of natural resources.
Besides refurbishing bearings, lubricants can also be reused in some cases. SKF’s RecondOil, for example, removes contaminants from used oils and restores them to a cleaner, usable, high-quality state. Compared to traditional and linear use, the regeneration of oils allows a significant reduction in CO2 emissions.
While the amount of steel per bearing is decreasing due to better bearing design and more efficient manufacturing methods, this steel still has value as scrap. However, not all bearings are easy to recycle and normally only certain parts of them can be recycled. Check with the manufacturer.
Beyond the product
The 3Rs are a good starting point for improving the durability of your bearings in use, but you cannot apply durability to the product in isolation. It is important to consider all aspects surrounding this product, including the manufacturer and its suppliers and distributors. Sustainability should encompass the use of raw materials; manufacturer’s plant processes and use of such materials; the amount and type of energy used to manufacture the bearings; distribution and transportation. Does the manufacturer deploy the ISO 14001 environmental management system and the ISO 50001 energy management system on all of its sites, for example? What are their Net Zero plans?
Reducing bearing waste isn’t just good for the planet, it’s also a good business decision. A bearing that performs well over a long period of time is a bearing that won’t slow machines down or cause costly unscheduled maintenance and downtime. Applying the 3 Rs to bearings is a good investment for the future, whichever way you look at it.
Alan Stewart is Rubix Bearing Product Manager at SKF Products. Rubix is one of Europe’s leading authorized bearing distributors, selling over 100 million bearings a year. Read its new bearing durability brochure, produced with bearing manufacturer SKF, at www.rubix.com/supplier/skf.