Print this page Metal Fatigue Excel Calculations
John Andrew, P.E.
Course Outline
Metal Fatigue Excel Calculations, is a 5 Professional Development Hour (PDH) online course having a series of input fatigue data and solved output equations in an Excel format. The student will type numerical values for machine design parameters and Excel will perform the calculations. For example, the proposed, time varying reversing loads on a shaft, are typed into labeled cells and the shaft diameter that will withstand the fatigue loading will be calculated for any safety factor.
Or any input parameter can be found for a target value of an Excel calculated item by using the "Goal Seek" tool in Excel.
The course includes
a multiple-choice quiz at the end, which is designed to enhance the understanding
of the course materials.
Learning Objective
At the conclusion of this course the student will:
- Have a spread sheet useful for machine fatigue design calculations;
- Adjust machine dimensions to meet fatigue design specifications;
- Document design calculations in a spread sheet format;
- Calculate stress and deflections of some typical machine elements;
- Fatigue analysis of power transmission shafting;
- Design of parts with notches and other stress concentrators;
- Determine rotating shaft dimensions;
- Convert US units to metric units;
- Distortion energy material failure theory is defined;
- Material shear yield stress is calculated based on tested tensile stress;
- Optimize bracket dimensions subject to fatigue loads;
- Calculate the strength and fatigue limits of shafts supporting gears;
- The most common fatigue testing method of metals is described;
- Corrected fatigue endurance limits of metals are calculated;
- Circular and non-circular sections are analyzed;
- Evaluate simple cantilever and beam deflections;
- Load, size, surface, temperature, and reliability factors are obtained;
- Fatigue stress VS number of cycles graph is calculated for widely used metals;
- Number of loading cycles to failure is calculated;
- Create spread sheets for more engineering applications; and
- Be able to employ
Excel's Goal Seek tool to optimize designs.
Intended Audience
The information will be especially useful to students, engineers, and innovators who need tools for creative machine designs subjected to fatigue loads.
Benefit to Attendees
Attendee of this
course will be able to calculate and optimize variables in a useful range of
machine fatigue design projects.
Course
Introduction
Machine design
calculations have been done with a calculator and written by hand with pen or
pencil. Optimizing design values with a calculator is difficult and time consuming.
Quite often it is impossible to read and check these hand written documents.
As time passes it becomes more difficult to find and use these documents to
make improvements to existing designs. However, Excel spread sheets out-perform
hand calculations and provide readable electronic and hard copy permanent records.
Excel spread sheets are used to calculate and optimize machine design parameters
more easily.
Course Content This 5 hour online course defines the design equations of several
basic examples of machine component subjected to cyclic loading resulting in
Excel print-outs of design parameters and calculated results. The Excel Workbook spread sheets are: Tab 1 Definitions Definitions: S-N Curve Notches Cantalever-1 Cantalever-2 Shafts
Tab 2 S-N Curve
Tab 3 Notches
Tab 4 Cantalever-1
Tab 5 Cantalever-2
Tab 6 Shafts
Conversions of conventional US engineering units and International Standard
units useful for fatigue calculations are provided. Principal stresses, strength
and fatigue failure theories, distortion energy or von Mises-Henky theory are
presented. Shear yield stress is calculated from the ultimate tensile strength
of most steel alloys.
Fully reversed, repeated, and fluctuating stresses are defined. Fatigue correction
factors are calculated for: load, size, surface finish, temperature, and reliability.
Fatigue endurance, Stress VS number of cycles, S-N graphs are plotted.
Static and fatigue endurance stress concentration factors for stepped shafts
and flat plates are estimated. Rectangular and round section properties are
calculated.
A cantilever bracket with notches, subjected to fully reversed bending stress,
is analyzed for fatigue endurance.
A cantilever bracket with notches, subjected to fluctuating bending stress,
is analyzed for fatigue endurance.
Two examples of fatigue bending and torsion of power transmission shafting is
estimated.
You need to download and study the following spreadsheet:
Metal Fatigue Excel Calculations
DISCLAMER:
"This spreadsheet is provided for illustrative teaching purpose only, and
is not intended for use in any specific project. Anyone making use of theinformation
contained in this spreadsheet does so at his/her own risk and assumes any and
all resulting liability arising therefrom."
Course
Summary
This course provides
Excel spread sheets to calculate a useful range of basic machine fatigue design
parameters. All variables can be adjusted to optimize design goals. Excel print-outs
of design parameters and calculated results provide easy to read documentation
for checking and future improvements.
Related
Links
Go to: http://www.PDHonline.com for PDH Course M236 - Machine Design Excel Calculations.
430,000 machine
items are described and priced at: http://www.mcmaster.com
Quiz
Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.
DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.
