DIN 2510-2:2025-04

This document specifies the nominal dimensions for bolted connections with a nominal thread diameter over 11,2 mm up to and including 180 mm (see DIN ISO 965-1) and with a waisted shank for tractive tightening methods as well as the limits of sizes for external threads and the tolerance classes for internal threads. The limits of sizes are intended for nuts with a nut height of m=1×d (see DIN 2510-5). Bolted connections with a waisted shank are particularly suitable for assemblies that are subject to variable working loads and changing temperatures (apparatus, piping systems, turbines). This document only lists fine pitch threads according to DIN ISO 965-1 for the next smaller pitch. In individual cases, the applicability to other fine pitch threads depends on the assembly preload F_M to be transmitted and the materials of the components to be connected. Screw threads according to this document correspond to the ISO metric screw thread according to the DIN 13 series of standards as well as according to DIN ISO 68-1, taking DIN ISO 965-1 into account. Larger fundamental deviations are provided for external threads in order to ensure the minimum pitch diameter clearance needed for bolted connections with waisted shank and for hydraulic tightening. In addition, the minimum clearance generated improves the loosening behaviour and reduces seizing for applications in the high-temperature range. This document has been prepared by Working Committee NA 152-02-01 AA "Gewinde" ("Screw threads") at DIN Standards Committee Technical Fundamentals (NATG).