Din 76-a Pdf May 2026
is a technical standard from the German Institute for Standardization (DIN) that specifies dimensions for thread run-outs thread undercuts
All dimensions are in millimetres. * Scope. This standard specifies dimensions for thread run-outs and thread undercuts for bolts, Thread Relief Explained: Function, DIN 76 & Practical Use din 76-a pdf
- It might refer to Shape A (Type A) undercut, which is the standard shape for external threads (flat bottom with radii).
- Shape B is used for boring (internal threads).
- It might simply be referring to the dimension column $a$ in a table.
(Radius): The curvature at the base of the undercut to prevent sharp corners that lead to fatigue cracking. Table: Common DIN 76-A Dimensions (Partial) Thread Pitch (P) 📋 Types of Undercuts in DIN 76 is a technical standard from the German Institute
The Problem Solver
: Without DIN 76-A, your bolts wouldn't sit flush against their surfaces. It defines the "relief" or undercut needed so that the threading tool doesn't crash into the shoulder of a part. It might refer to Shape A (Type A)