By Travis Shive | Analytical Tools Expert • SKF USA Inc.
Bearings are a fundamental part of any machine — which is why the design of their moving elements can mean the difference between an efficient machine and one that continually wears out and breaks down. So now, some manufacturers offer bearing-simulation software tools to support everything from from entry-level design to complex machine designs necessitating internal analysis.
One engineer-facing software lets designers analyze single-shaft designs. This lets design engineers use the software themselves to modify the machine-axis shaft to existing dimensions … and then adjust the bearing arrangement and surrounding gears and spring spacers as well as other components nearby in the assembly. Engineers can then assess the performance of variations on a given design to predict bearing subsurface fatigue life as well as possible performance conditions that could spur a premature end of bearing life. Such software can warn of surface damage that may go unaccounted when bearing-life calculations are based on traditional catalog-calculation methods.
Such entry-level bearing-design software is relatively straightforward and easy to use … in some cases, with a drag-and-drop interface for adding in components. Such design software also lets users see bearing inner and outer-ring rotation as well as bearing stiffness represented in a matrix.
More sophisticated software goes beyond single-shaft equipment to let engineers build more complex models — such as multiple-shaft models to virtualize a gearbox series, for example. That in turn allows:
- Analysis of how one shaft in the assembly can affect other shafts
- Quantify the supporting properties of any housing in the assembly
- Importation of any OEM or end-user CAD components into the software for more realistic design confirmation
- Sophisticated thermal analyses to predict the temperatures of components during operation
Still more sophisticated are simulation services to help in bearing sizing and selection. These are services executed by the bearing manufacturer; such simulation generates more in-depth profiling than any software offered for engineers to use themselves. In many cases, the analysis of such programs yields in-depth information about micro-level contacts between the bearing rolling element and the rings — in addition to factors such as roller deflection and skewing. Bearing manufacturers can also supply detailed information about the cage that holds the bearing’s rolling elements — including the way in which the cage and the balls or rolling elements interact.
Value-add engineering support with software
Consider how an OEM might notice vibration in their system on after an initial machine build. Such OEMs can often measure the amplitude of vibration but not whether it’s acceptable for the bearings in the system. Here, a bearing manufacturer can intervene with software analysis — virtually applying the vibration the OEM measures to a digital twin of the design at the bearing’s outer ring. Next comes an investigation of how everything inside the bearing moving as a function of this vibration. One potential problem is the way the rolling elements impact the cage. The question ultimately becomes: Will the cage last? In this situation, cage examination to document force levels can yield a recommended vibration reduction for sufficiently long cage life and a longer machine-axis mean time before failure.
Software tools are changing how design engineering is done
Bearing simulation software offers benefits to engineers in a wide range of industries — including off-highway, pumps and systems, pulp and paper, automotive, wind, mining, and aerospace. Some of the advantages that come with using this software are that design engineers have more insight into (and control over) the finer details of a given application … which can help them optimize their bearing selections.
Design engineering software also lets OEMs and end users work more quickly and with more power in their hands. It cuts down the amount of time spent in testing, which in turn reduces development expenses. With software, a design engineer might devise four different designs — and then simply identify which one is the most economical with the best technical attributes.
Consider a manufacturer of high-end textile machinery. Here, the objective might be to design bearing arrangements that help increase machine speed and accuracy. The bearing running accuracy is critical … software can help such OEMs quicken their design process while evaluating optimal bearing arrangements without external help.
