ME Analysis Project #2
Due Date: December 12, 2013
The diameter for my shaft design was hand calculated to be 0.8756” for a factor of safety or 2. This factor of safety was expected to be the outcome in FEA SolidWorks and it was not. The reason for this is simply SolidWorks is not the best tool to use for complex designs and loads as ours was. It worked great for the simple beam deflection in the last project. Many times hand calculations are the long way of doing things. In this case, it took much longer to figure out the correct way of adding fixtures, load, and connections in SolidWorks. Many of the material properties in SolidWorks are also not ...view middle of the document...
The first step in designing this shaft is to calculate the statics of the shaft. You will have to pay extra attention to the areas you think are of concern. In this case, it will be the area of the shaft right before the roller. The maximum moment will be calculated from shear and bending diagrams. Once the alternate moment and mean torsion are calculate the endurance limit must be calculated. Here is where the material of the shaft will be chosen. Stress risers will be calculated next for the area of concern right before the roller. Once all of this data is hand calculated it can be placed into an excel worksheet. The worksheet will back solve an appropriate diameter given a factor of safety. This shaft will be created in SolidWorks will be compared to see how well FEA SolidWorks performs.
Results and Discussions:
Statics has been calculated below in both the x-y and x-z planes. The mean torque is equal to 192 lbf. The alternating moment is equal to 375 lbf-in. Both the alternating torque and mean moments are equal to zero.
Once the Statics was figured out I went straight to choose the material. I chose 1020 CR steel because it is very often used as a shaft. The Endurance limit was calculated next. I left k_b as an equation in my excel program so it would change with the diameter. Stress concentration factors were used for the fillets between the shaft and...