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The rotary draw bending process finds special use in the bending of parts with small bending radii. Due to the support of the forming zone during the bending process, semi-finished products with small wall thicknesses can be bent. One typical quality characteristic is the emergence of corrugations and wrinkles at the inside arc. Presently, the standard for the evaluation of wrinkles is insufficient. The wrinkles’ distribution along the longitudinal axis of the tube results in an average value [1]. An evaluation of the wrinkles is not carried out. Due to the lack of an adequate basis of assessment, coordination problems between customers and suppliers occur. They result from an imprecision caused by the lack of quantitative evaluability of the geometric deviations at the inside arc. The benchmark factor for the inside arc presented in this article is an approach to holistically evaluate the geometric deviations at the inside arc. The classification of geometric deviations is carried out according to the area of the geometric characteristics and the respective flank angles.