Remanufacturing bearings for a better circular economy

BEARING REMANUFACTURING is the process of restoring used or worn-out bearings to their original or improved operating condition. As an end-of-life management solution it is gaining popularity, and for good reason. Not only do remanufactured bearings offer a cost-effective solution for businesses, but according to SKF, the process reduces the amount of raw material needed by around 62%.

How does it work?

Remanufactured bearings can use a combination of reused, repaired, and new parts, and bearings with more than 30% of their remaining service life can be remanufactured. A thorough inspection is conducted to determine the appropriate refurbishment process. The process involves several steps, including inspection, reclassification, refurbishment, and remanufacturing.

The first step is to inspect the used bearing thoroughly, which involves comparing it with the initial specification drawing. The bearing is then disassembled, cleaned, and degreased. Following a visual inspection, microscopic inspection, dimensional inspection and testing will occur. This will culminate in a detailed analysis report that details recommendations for appropriate refurbishment and remanufacturing processes.

The next step is reclassification services, which encompass minor repair, demagnetisation, dynamic testing, relubrication, reassembly, and packaging for the bearing’s return to the industry.

If further intervention is needed, then refurbishment might be necessary. This step will include the previous actions in addition to one or more of the following: replacing rolling elements or components like seals and snap rings, remanufacturing the bearing's cage, plating mounting surfaces or polishing the bearing’s raceways.

The final stage of remanufacturing involves altering the component by grinding, installing a new ring and modifying it. At this point, engineers have the option to enhance the performance or characteristics of the initial bearing, which can lead to increased operational efficiency and reduced maintenance requirements in the future. Upgrades may include the addition of features such as black oxidation, or the incorporation of extra sensor functions for condition monitoring.

Economic benefits 

Replacing a worn bearing can be costly and, in many cases, remanufacturing can provide significant cost savings. For example, if a large industrial bearing in a pumping system fails unexpectedly before the end of its service life, remanufacturing could increase the life cycle of the bearing by more than 50%, and provide up to 60% savings compared to the cost of a new bearing.

Smaller bearings, like miniature bearings, may not be cost-effective to remanufacture. This is due to the cost of disassembling, cleaning, inspecting, and reassembling the bearing, which may be higher than the cost of simply replacing the bearing with a new one. Additionally, the amount of wear and damage that can be repaired on small bearings may be limited, making remanufacturing less practical.

Remanufacturing larger bearings, on the other hand, offers a favourable cost-benefit depending on their condition, complexity, price and application. Large bearings - such as spherical roller bearings, deep groove ball bearings, tapered roller bearings, caster bearings and slewing bearings - are good candidates for remanufacturing.

Additionally, relubrication services, such as those offered by the bearing relubrication specialist SMB Bearings, can extend a bearing's service life and improve operational performance at an affordable price point. Indeed, relubrication is crucial if you intend to repurpose old-yet-healthy bearings for a different application.

Chris Johnson is MD at SMB Bearings

For more information: 

www.smbbearings.com

Tel: 01993 842 555