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GD&T Symbol - Concentricity (2018)

See Concentricity (1994 & 2009)

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GD&T Symbol - Concentricity

Concentricity has long been a misunderstood and misused geometric tolerance. Control of derived median points has very few practical applications and is difficult to inspect. It has frequently been misused since many people want features to be "concentric" (coaxial). There are other geometric controls which offer much better ways to achieve this. Therefore, Concentricity has been removed from the Standard.

The options for controlling locating coaxial features are position, circular runout and total runout, and profile. Which you choose depends on the application:

GD&T Symbol - Concentricity

When used with a size dimension, which usually controls form, several of these controls will likely be acceptable for the design function.