DIN 3771 is a now withdrawn standard for the use of O-rings as seals for fluid technology. The standard was replaced in 2010 by the international standard ISO 3601, which incorporates many of the specifications of DIN 3771.
Until it was replaced, DIN 3771 was used as the standard for the general technical application of O-rings. It has a comprehensive regulatory scope with regard to the selection, use and quality control of O-rings. The standard is divided into five parts:
- Dimensions
- Testing and labeling
- Field of application
- Shape and surface deviations
- Calculation method and dimensions of the installation spaces