About bushing surface roughness..

[serdart]

Hey everyone,

As a project, I will measure the surface profile of a bushing, which will be worn on a test rig. This bushing will be press-fit to its housing. I need to measure the profile, before and after the test.

Does it differ if I do the measurement when the bush is fitted in the housing, or After I pressed it out of the housing. I mean, does the press-fitting process influence the surface measurement results?

Thx..

 

[israelkk]

If the press fit is tight the bushing may have buckle and will have some waviness in its inside diameter which will influence the profile. Since the press fit depends on the bushing outside diameter tolerances and the hole tolerances in the housing the surface roughness inside the bushing will vary. Anyway, the bushing has no practical use outside the housing therefore, the correct way is to check the surface roughness when it is assembled. You can test the effect of press fit tightness as a result of the bushing and hole sizes and tolerances on the surface roughness after assembly compared to the original surface roughness of the bushing before press fitting it.