New Features in Version 10/2018 of MESYS Shaft and Bearing Calculation Software

 

A new version of the MESYS shaft and rolling bearing analysis software including new functionality is available. The bearing analysis software allows the calculation of the load distribution within the bearing and bearing life according ISO/TS 16281 and it is integrated in a shaft system calculation with additional possibilities like modal analysis, strength calculation for shafts and interfaces to gear calculations. Currently the software is used by customers in 25 countries on 4 continents.

Calculation of shaft stiffness for selected points

The software can now directly derive the stiffness of a shaft system for selected points. Therefore it is not necessary any more to run two calculations to derive a value for a system stiffness and the output of stiffness is available too in parameter variations. The stiffness is available for translations in the three directions of axis and for rotation around the three axes of the local coordinate system.

Bearing databases

The existing database with SKF catalog data was updated and a new database with catalog data from Schaeffler containing FAG and INA bearings was added.

REXS-format for data exchange

The REXS-format for data exchange with other calculation programs was added to the shaft system calculation. See www.rexs.info about information regarding the standard. Shaft systems including bearings and coupling by cylindrical and bevel gears can be exported or imported. Also load spectra are considered in the definition. This standard format should allow data exchange with other CAE programs.

Extensions for FEA integration

A large extent in version 10/2018 has the improved integration of FEA calculations into the software.

Now hexahedral and tetrahedral meshes can be generated using the integrated meshers. Second order elements should be used with tetrahedral elements.

Forces and supports can be defined directly on imported 3D-elastic parts. This allows to add forces on a housing or to define additional stiffness supporting a housing.

Version 10/2018 allows to consider elastic bearing rings and elastic gear bodies for cylindrical gears.

The following images show the shaft deflection and the line load for five different gear bodies. The first two cases use a beam model with a full or reduced diameter for the gear body. The following three cases use a FEA model for the gear stiffness. Using a beam model only, the diameter used for the gear body for a full cylindrical gear can be defined as the root diameter of the gears (plus some small amount for stiffness of the teeth, case 1) with leads to similar results for the flank line deformations like in case 4 with a full cylinder as FEA model. But it leads to smaller deflection of the shaft. Using a smaller diameter for the gear body in the beam model leads to larger shaft deflection, but it also leads to larger deflections of the flank line which is unwanted (Case 2). Using the FEA based gear body, both shaft deflection and flank line deformations can be considered more accurately.

The elastic deformations of bearing rings lead to differences in the load distribution within the bearings as can be seen in the following simple example with a horizontal load on the bearing. The left case does not consider deformations of the bearing and the right image takes into account these deformations of the bearing rings.

Either only the stiffness of the FEA parts is taken into account and its deformation is used for the deformation of the bearing ring or an additional stiffness of the bearing ring itself is considered.

Another example for the stress distribution in a large bearing with elastic rings is shown in following image. The stiffening effect of the housing can be especially seen in the back bearing.

After a one-time condensation for 3D-elastic FEA based parts the calculation time is seconds as with the beam model. Therefore parameter variations of load spectra can be considered like for the beam models.

Contact
MESYS AG
Technoparkstrasse 1
CH-8005 Zürich
Tel:+41 44 455 6800
Email:info@mesys.ch