C-ring load equation,

[bogiedreamer]

Does any one know the equation for calculating the load exerts by a C-ring? For example, a C-ring with 1.000” OD, 0.020” thickness, 0.125” width and 0.060” gap. If the C-ring is deflected by 0.050” so that the gap now is approximately 0.010”, then what is the load?

I would like to have an equation so that I can vary the spring thickness to achieve the desired load.

Thanks,
Bogiedreamer

 

[ivymike]

do you want load expressed as pressure, or load expressed as a force couple acting through the ring center, or load expressed as a force acting at the ring tips? In any case, you can probably find your answer by searching online for "calculating piston ring tension."

 

[desertfox]

Hi bogiedreamer

You can find your answer in most strength of materials books under curved beams using a strain energy method.

regards desertfox

 

[israelkk]

DESIGN HANDBOOK Engineering Guide to Spring Design 1987 Edition, Associated Spring-Barnes, pages 67-69

http://www.webspawner.com/users/israelkk/

 

[zekeman]

Integralof M^2/2EIr*d@ from 0 to 2pi is strain energy.
where I use @ for the angle theta since I don't have Greek letters
M=Fr(1-cosine@). So
Energy=Integral{F^2*r^3*(1-2cos@+cos^2@)/EI*dtheta -limits 0 to 2pi
Since cos^2@= (1+ cos 2@)/2
This integral becomes
3pi*F^2*r^3/2EI and the deflection is the derivative of Energy with respect to F or
defl=3piFr^3/EI
This should be enough to get you to a thickness for a given force and deflection.