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Geometric tolerances Concentricity

by asteorit
Tags: concentricity, geometric, tolerances
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Jun4-14, 02:06 PM
P: 15

I need help. I do not know what to give values of the geometrical tolerance for Concentricity. They are two parts connected by a pin. Both parts are moving relative to each.

Thanks for any advice.
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Jun4-14, 03:14 PM
P: 463
More details needed.

Concentricity is usually necessary when you have two circular features in ONE part and you would like them to be concentric for some mechanical reason. If you have two moving parts with one pin, they will move without any problems as long as you give the proper tolerances for the chosen Fit for pin and hole.

E.g. common values for concentricity are 0.02, 0.05mm or inbetweens (no idea in inches), although diferent values are needed for diferent sizes and fine parts. That should mean that if measured the central axis of the two concentric features which sit on the same part do not distance themselves more than half of 0.02-0.05mm at any point (If I remember right).

A usual standard is DIN EN ISO 1101 (2006-2). Google it or get a similar in imperial if neccesary.

IMHO you need the things in DIN ISO 286-1 (1990-11) which are standardized Fits for holes and shafts.

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