Contact Stresses in Cantilevered Journal Bearing

[jsed]

I am trying to analyze the static stresses on a bronze bushing in a journal bearing if I was to use that journal bearing as a support for a cantilevered shaft. All the equations I have for contact stresses on the bushing suggest a uniformly distributed load across the entire bushing, which would be applicable if the shaft were supported by two bearings, but I am interested in what happens when the shaft is only supported on one end by one bearing.

Also, the manufacturer of the bushing states that the bushing can withstand 8000 psi of static load, which represents the load on the projected bearing area (ID x Length). Based on this criteria, I am not sure if contact stresses are what I need to be looking at. I also know the compressive yield strength of the bushing material, so I could just use that to analyze the static failure of the material.

Thank you for your input.

 

[JBA]

For any reasonable responses you should give a diagram of what you are describing.

Speaking in general terms, static loading failure is not going to be your primary problem. The effect of the cantilevered shaft is going to depend upon the amount of lateral load or weight on the extended shaft. Using a single bearing with a cantilevered shaft is going to result in small contact areas at the edge of each end of the bearing, one at the top on the end opposite the cantilevered load and one at the bottom on the cantilevered end. The result,depending upon the bearing material (polymer vs metal), the amount of load and the rpm of the shaft, is most likely to be either very quick wearing or galling of the bearing at those two points.