Steel tables for calculating axle diameter

Click For Summary

Discussion Overview

The discussion revolves around calculating the appropriate diameter for an axle based on bending moments and material properties. Participants explore various methods for determining axle dimensions, including the use of steel tables and engineering handbooks, while addressing the complexities of stress analysis involving bending and torsion.

Discussion Character

  • Technical explanation
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant proposes using the equation Sx = M/Fy to calculate the plastic modulus for axle design, seeking guidance on accessing steel tables.
  • Another participant recalls a shaft design method learned in university that involves calculating maximum stress from combined loads, including bending and torsion, and emphasizes the importance of selecting appropriate steel types based on yield strength.
  • Several participants suggest consulting engineering handbooks or suppliers for steel properties and design guidelines.
  • Concerns are raised about using tubular materials for axles due to potential catastrophic failure risks associated with wall collapse.
  • Participants discuss the necessity of considering both bending and torsional stresses in the stress analysis, especially if the axle will carry torque.
  • One participant questions the applicability of certain equations for a rotating shaft and highlights the significance of fatigue in design considerations.
  • Another participant inquires about determining axial thrust loads and factors that may influence this calculation.
  • Questions are posed regarding the practical limits of axle diameter and the availability of stock sizes that could be used effectively.

Areas of Agreement / Disagreement

Participants express various viewpoints on the methods and considerations for axle design, indicating that there is no consensus on a single approach or solution. Multiple competing views remain regarding the best practices for calculating axle diameter and the associated stresses.

Contextual Notes

Participants note the complexity of stress analysis, particularly when combining bending and torsional loads, and the potential for fatigue issues in rotating shafts. There are also references to the need for iterative design processes and the importance of using standard stock sizes in practical applications.

Who May Find This Useful

Individuals involved in mechanical design, engineering students, and professionals working with axle design or similar structural applications may find this discussion relevant.

  • #31
Ah yes, I forgot to convert to MPa.

I am familiar with deflection however not sure how to calculate it under these parameters, could you give me some pointers?
 
Engineering news on Phys.org
  • #32
Just to be clear on one point - Is there another extension and load at the other end of the axle ?
 
  • Like
Likes   Reactions: Wilson123
  • #33
No there isn't, my design has one axle per wheel, so the other wheel is supported by a mirror image of this axle.
 
  • #34
After looking over my calculations, I've realized I had my bending moment slightly too high, therefore my bending stress is wrong. My bending stress is actually 63MPa.
 
  • #35
Do you still want any help with this problem ?
 
  • #36
@JBA has kindly provided this reference to formulas for stress and deflection in another thread . You can use these formulas for your problem as well .
 

Similar threads

Replies
33
Views
5K
Replies
37
Views
6K
  • · Replies 10 ·
Replies
10
Views
5K
Replies
1
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 1 ·
Replies
1
Views
7K
  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 4 ·
Replies
4
Views
8K
  • · Replies 2 ·
Replies
2
Views
5K