The keyword refers to a highly specific mechanical engineering specification for a Type E relief groove (undercut) as defined by the German Institute for Standardization (DIN) . In precision manufacturing, these undercuts are essential for ensuring that mating parts—such as a shaft and a bearing—can fit perfectly against a shoulder without interference from the naturally occurring radius left by a cutting tool.
Sharp 90-degree transitions create severe stress concentrations. Under cyclic mechanical loads, these corners act as crack initiation sites, leading to sudden fatigue failure. The 0.6 mm radius transitions the grain structure of the metal smoothly, dispersing stress lines and vastly improving the fatigue life of the shaft.
: The standard could be designed for products intended for specialized applications where general standards do not suffice, such as in aerospace, high-performance industrial machinery, or advanced medical devices. din 509e06x02 exclusive
: Ensuring that bolts or screws sit flush against a surface without interference from a corner radius.
refers to a specific type of relief groove (or undercut) used in mechanical engineering, typically situated at the root of an external thread. The keyword refers to a highly specific mechanical
A single solid line pointing to the junction corner with a leader note reading: Freistich DIN 509 – E 0,6 x 0,2 .
(shoulder) does not require high precision or is not subjected to high fatigue loads. Under cyclic mechanical loads, these corners act as
This article is for informational purposes. Always consult the latest DIN EN ISO standards and your specific supplier’s technical data sheet before specifying proprietary coatings.