Technical specifications and application range of DIN 9021 washers
The DIN 9021 standard regulates the production of flat washers with an increased outer diameter, belonging to accuracy classes A and C. A structural feature of this fastener is that the outer diameter of the product is approximately three times the nominal thread diameter of the mating bolt or screw. This design allows for a significant reduction in specific pressure on the bearing surface, which is critical when mounting into soft materials or when dealing with oversized mounting holes.
EV Group China engineers recommend using these washers in critical assemblies together with hexagon bolts and nuts that comply with ISO 272 specifications to ensure uniform load distribution on the structure.
Important note: The DIN 9021 standard is considered obsolete and has been replaced by the current international standards DIN EN ISO 7093-1:2000-11 and DIN EN ISO 7093-2:2000-11. When designing new assemblies, it is recommended to switch to using the specified ISO standards.