Hey,
Here is one reference I found with a fatigue curve. Take it with a grain of salt. According to this reference using properties for 7050 should be conservative lacking any fatigue data for 7085.
http://www.materialsaustralia.com/Materials_Forum/Vol28/GP%20141.pdf
Good luck
Greg,
The shaft in question has flexible diaphragms on both the driven and driving ends. These diaphragms are very stiff torsionally but can accomodate axial deflections. the torque load is steady (from an turbofan engine). Axial deflections will be intermittant due to accelerations during...
In my case the spline needs to accomodate transient axial motion and thermal growth. I needed to calculate the force required to move the spline axially through the female spline. Wow! I just noticed that my spelling is terrible. sorry about that.
Thanks to all
you might want to try books listed or recommended on the Vibration Institute's website. Two i can recommend are Charles Jackson's "Pratical vibration Primer" and Taylor's "Vibration Analysis Handbook"
Hello,
My experience with equipment vibration/health monitoring using acoustics is that it is not effective if the equipment you are monitoring is in a high noise environment. We had a company try to predict bearing failures on a high speed aircraft gearbox using what they call "stress wave...
Thanks Greg,
But I still need to calculate the spline tooth load under the given torque and speed. What formula would you recommend to derive the tranmitted load? I know that the lewid formula is used for spur gears. Would this apply to splines which have a much higher contact area??
Keith
here's a challenging problem.
How would one calculated the min axial force required to cause an involute spline to slip under a continuous torque. This is for a long drive shaft with male spline on one end mating with a female spline (with roon for axial movement). The design requires that...
Thanks to all for responding. It is always good to see others opinions on a complex subject. I spoke with the folks at MSC and they said the same thing regarding a modal analysis- no constraints. The first six modes will be rigid body modes. Next i will put in constraints and damping to...
Hey,
Any FEA guys out there? I have modeled a gear in PATRAN in order to determine the natural frequencies and mode shapes. My question is: How should I constrain the model? I noticed that the results are very sensitive to how the model is constrained. I simply constrained one node...
Thanks Chappy, I have found all except for the following out of print book.
Kuhn, P. "Stresses in Aircraft and Shell Structures", McGraw Hill, 1956.
My e-mail is rowleykl@navair.navy.mil
Hello,
I am looking for a few old aerospace technical books.
Mangurian, G.N. & Johnston, N.M. "Aircraft Structural Analysis" Prentice Hall, INC. 1947
Shanley, F.R. "Weight Strength Analysis of Aircraft structures", The Rand Corp. 1952
Kuhn, P. "Stresses in...
ERWIN,
The S/N curves show the cycles to failure (or frequency of applied load) on a test specimen, i.e, an Aluminum rod or plate sample. Which curve you use depends on the nature of the applied load (load ratio R). For example if you subject a test specimen to a fully reversed load (from...
