TS EN ISO 14660-2

TS EN ISO 14660-2 is a geometrical products specification standard that defines specific extracted features derived from workpieces: the extracted median line of a cylinder and a cone, the extracted median surface, and the local size of an extracted feature. It helps separate the geometry of a real manufactured surface from the idealised geometry used in drawings and measurement interpretation, so that the same terms can be used consistently in design, metrology and inspection.

What the extracted features represent

In general technical terms, an "extracted" feature is obtained from measured points on the actual surface, rather than being assumed from the nominal model alone. For a cylinder or cone, the median line represents a central geometric line associated with the feature; the median surface expresses an intermediate surface related to the measured shape; and local size describes the dimension associated with a limited portion of the feature instead of a single overall size value. These distinctions matter because size, form and local variation are not interchangeable in geometry control.

Why this terminology matters in practice

• It supports a clear distinction between overall size and local dimensional behaviour.
• It standardises naming for median-line and median-surface concepts used with cylindrical and conical features.
• It improves consistency in inspection, drawing interpretation and coordinate metrology.
• Together with TS EN ISO 14660-1, it contributes to the common GPS language for geometrical features.