DIN 1587 Hexagon Domed Cap Nuts

DIN 1587 Hexagon Domed Cap Nuts are high-form cap nuts with a hexagonal body and a rounded closed end. The threaded opening allows the nut to be installed on a matching metric threaded fastener, while the domed section covers the exposed end of the assembly. The standard defines the dimensional form of this type of cap nut and remains a commonly specified DIN fastener without a direct ISO equivalent. DIN 1587 is also commonly described in the market as a domed cap nut, cap nut, or acorn nut.

The closed dome serves a practical purpose in addition to its finished appearance. It covers the projecting end of a bolt or stud, reducing direct exposure of the thread and helping prevent contact with sharp or protruding thread ends. This makes the fastener useful where the appearance and physical protection of an exposed threaded connection are both relevant. Typical applications include machinery, equipment, fabricated assemblies, fixtures, furniture, fitness equipment, and other products where exposed threads need to be covered.

DIN 1587 cap nuts are available in common metric thread sizes and can be supplied in materials such as carbon steel and stainless steel. Standard references show sizes extending from small metric diameters through larger industrial sizes, although the commercially available range depends on the material, finish, and supplier.Common supply options include plain or zinc-plated steel and bright stainless steel versions, with stainless grades such as A2-70 and A4-70 available in commercial product ranges.