DIN 935 specifies the dimensions and tolerances for castle nuts (din 935). The full dimensional table is reproduced below, followed by the DIN, ISO and ASME parts that match or supersede it.
- Standard
- DIN 935
- Product
- Castle Nuts (DIN 935)
- Governing standards
- DIN 935
Equivalence between national standards is dimensional, not always metallurgical. Check the property class separately when substituting.
The table below lists the dimensions catalogued for castle nuts (din 935) under DIN 935. The scope of DIN 935 itself is not summarised here — where a figure matters, confirm it against the published document.
DIN 935 — Scope
The table below lists the dimensions catalogued for castle nuts (din 935) under DIN 935. The scope of DIN 935 itself is not summarised here — where a figure matters, confirm it against the published document.
Tolerance & Product Grades
Product grade is a concept from dimensional fastener standards and does not apply to DIN 935. Tolerances for this part are the limits shown against each dimension in the table.
Dimensions Specified by DIN 935
| Thread size | Pitch (mm) | Width across flats s (mm) | Total height m (mm) | Slot width n (mm) | Slot depth (mm) | Split pin size | Reference standard |
|---|
| M8 | 1.25 | 13.0 | 9.5 | 2.5 | 3.5 | 2 x 25 | DIN 935 |
| M10 | 1.5 | 17.0 | 11.5 | 2.8 | 4.0 | 2.5 x 30 | DIN 935 |
| M12 | 1.75 | 19.0 | 14.0 | 3.5 | 5.5 | 3.2 x 36 | DIN 935 |
| M16 | 2.0 | 24.0 | 17.0 | 4.5 | 6.0 | 4 x 40 | DIN 935 |
| M20 | 2.5 | 30.0 | 20.0 | 4.5 | 6.0 | 4 x 50 | DIN 935 |
| M24 | 3.0 | 36.0 | 24.0 | 5.5 | 8.0 | 5 x 63 | DIN 935 |
Companion Standards
A complete specification for castle nuts (din 935) normally cites several documents: one for the geometry, one for the material or mechanical properties, and one for the finish. DIN 935 is one of them, not all of them.
When to Specify DIN 935
DIN 935 is still widely used in European mechanical engineering and as a cross-reference on legacy drawings; its ISO equivalent is preferred for new designs.
Custom manufacturing · Made to drawing
Need a nut to this standard in a non-standard size?
Parts built to DIN 935 are already in the catalog, so a special is usually a variation on existing tooling rather than a new design — which is what keeps the cost down. Made by cold heading or tapping.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
Custom nut manufacturingSend a drawing
Applications & Industries
What Castle Nuts are specified for, industry by industry. Stocked from M8 to M24.
Industries that specify Castle Nuts
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Agricultural & plant
Articulating joints not meant to be torqued solid.
-
Rail & heavy equipment
Inspectable, positively locked joints.
-
Automotive chassis
Wheel bearings, steering and suspension joints locked by a split pin.
-
Maintenance & MRO
Replacements matched to the existing bolt class, thread and finish.
-
Building services
Threaded rod, channel and suspension assemblies.
-
Machine building & OEM
The clamping counter-face on studs and bolts throughout an assembly.
Typical applications
- joints deliberately left free to articulate
- tighten to torque, then back off to the nearest slot
- positive locking with a split pin through a cross-drilled bolt
- locking an adjustment so it cannot drift
- joints re-torqued at a service interval
- completing a bolted joint on a stud, rod or bolt
Service conditions to specify against
- Marine and coastal
- Available in A4 (316) stainless for chloride exposure — coastal structures, pool halls, water treatment and deck hardware, where A2 will eventually pit.
- High load
- Supplied in ISO 898-1 property classes, so the joint can be designed to a stated proof load and tightened to a calculated torque rather than by feel.
- Match the class
- A nut below the bolt property class strips before the bolt reaches its own limit — pair class 8 nuts with 8.8 bolts, class 10 with 10.9.
Full application guide: where Castle Nuts are used, how to specify them, and the cases they are wrong for
