In cement processing applications, increased production demands, longer running times and more corrosive environments are putting machinery under pressure. As crucial components in the operational efficiency of any machine, bearings must be able to withstand increasing forces and runtime. Chris Ager, Business Unit Manager at Bowman International, explores the increasing importance of load types in industrial applications and how innovation in bearing design can help to avoid system failure, unplanned downtime, and increased maintenance costs.
Understanding forces: axial and radial
When choosing the right bearing for the job, it is important to understand the load and application requirements. If the wrong bearing is used, it may not carry the required load effectively, leading to damage and potential failure. There are two main types of load – radial load refers to the loads acting at right angles to the shaft, and axial loads are applied parallel to the shaft in both directions. While many bearings are designed to handle either axial or radial loads, high-load applications in heavy side industrial applications often require a combination of the two – a requirement that, due to limitations in manufacturing, has been left largely unmet.
To best serve the needs of high-load applications that have both types of forces in play, many bearing manufacturers and OEMs will use a combination approach – using a pair of bearings to accommodate the load in each direction. The shortcomings of this method mean more space requirements within the machinery – increasing its overall footprint on the factory floor – as well as potential complications with both assembly and access for ongoing maintenance.
While there is an increasing number of bearings on the market that are designed to handle both radial and axial loads, they work by inclining the rolling elements to give some axial capacity. In doing so, they trade off radial capacity for axial – a solution that limits the axial load capacity, limiting application usage or putting the bearings at risk of failure.
Both radial and axial load specifications directly relate to the strength and rigidity of the bearings, shaft, and overall machinery. Exceeding these specifications in an application with a high axial load may result in damage to the bearing and have a different impact on efficiency. In fact, studies suggest that exceeding either radial or axial load specifications by 10% may reduce the lifespan of the components by about 1,000 hours – as well as running the very real risk of unplanned downtime. For applications with a high axial load, these solutions are far from ideal.
Innovations in bearing design
In a standard split bearing design, the rollers run against the outer race lips and clamp rings on the inner race assembly of the bearing, creating stress, friction, and a lower tolerance for axial loads. Using engineering-grade 3D-printed Nylon-11 and the latest additive manufacturing technology, Bowman has been able to create a bearing design that removes the axial locating lips from the bearing outer race. This means that the radial roller length, as well as the actual number of rollers, can be increased – giving both a higher load capacity and an approximate increase of x5 radial L10 life.
Increased axial capacity
By adding axial roller and cage assemblies to their design, Bowman has overcome the issue of reductions in axial load by using three sets of rolling elements to allow independent handling of the radial and bi-directional axial loads. The design incorporates the usual benefits of a split bearing system such as faster removal and installation processes when compared to solid bearings, while increasing the radial capacity and significantly improving the axial capacity compared to standard solutions.
To find out more information about how advanced bearing design can benefit cement processing facilities, and the state-of-the-art innovations Bowman International has brought to market to solve these challenges, contact the team today.