Round Thread DIN 20400
The round thread according to DIN 20400 is a special type of round thread for use in mining. Round threads are generally characterized by their robustness and resistance to dirt, corrosion, and mechanical wear, making them frequently used in so-called harsh working environments to reduce cleaning and maintenance efforts. The commonly used variant of the round thread according to DIN 405 proved unsuitable for underground mining operations, leading to the design of the special round thread DIN 20400 specifically for this application. The DIN 20400 round thread has a large load-bearing depth with comparatively low strain on the thread flanks.
The flank angle of the DIN 20400 round thread is 30°. It is a metric thread, with both nominal diameter and pitch given in mm.
The thread designation consists of the abbreviation Rd and the nominal diameter in mm, for example, Rd 14. It should not be confused with the round thread DIN 405, where the pitch is also included in the thread designation.
The DIN 20400 round thread has different nominal profiles for external and internal threads. Consequently, the thread table includes dimensions for the external diameter and core diameter for both bolts and nuts. The pitch in mm is also listed. The DIN 20400 round thread is a specialty thread with a narrowly defined application area. If you require dies or taps for the DIN 20400 round thread for mining, please contact us with your request, and we will manufacture the tools according to your needs.