# Mechanical Engineering Multiple Questions And Answers

Name _____________________________ Hw 10 ME 222 (Spring 2021)
1. Find the following parts and provide the part numbers. (9 pts)
a) Fastener, slightly corrosive environment, strength required =100 Ksi, pitch = 2mm, diameter =
14 mm, length = 60mm, thread length = 34mm, hex head (mcmaster.com)
b) Rack and pinion, high load, pressure angle = 20°, face width = 1.5”, pitch diameter = 3.5”, length
= 2’ (mcmaster.com)
AC to AC transformer, 120V input, 3A max current (mcmastercar.com)
2. Answer the following regarding the uncertainty in FEA reading. (5 pts)
a) What is the minimum number of element through the thickness of a curved component using
b) Between stainless steel and cast iron, which material properties are generally more repeatable?
c) What is the greatest source of FEA uncertainty that you can control?
d) Why are boundary conditions like pins and rollers used?
Is a basic SW FEA solution valid if your component experiences large displacements?
3. Create a static analysis for the shelf bracket model and perform a mesh refinement study. Use Nylon
6/10 for the material, 50 lb for the force on the front area, and global size controls for the mesh.
Produce a plot of number of nodes vs Factor of Safety and use at least 5 points. What is the FoS
convergence value and number of nodes required? (10 pts)
4. Once your mesh refinement study has been completed, perform a material selection study by
comparing the minimum factors of safety and component weight for at least 5 materials. Produce a
plot with materials labeled. (5pts)
5. Use the slot subroutine to complete the following list of slots. Submit a CAMotics project. (5 pts)
Xc Yc Length Width Depth
1 0 0 50 3.5 20
2 -20 100 75 10 21.25
3 20 -100 20 20 10
4 -20 -100 37.5 3.5 20
5 20 100 50 5 25
6. Modify the subroutine to accommodate slots in any orientation. Create a CAMotics project to
simulate the figure below. The slots should be 21mm deep in a 50mm material. Use a 6mm
cylindrical bit with a plunge ratio of 50/500. Submit the CAMotics project and requisite files. (10 pts)