Square Nuts are used primarily for channel, strut and woodwork where a non-rotating, large-bearing nut is needed. This page summarizes where they fit, the industries that rely on them, and the practical points to get right when you specify them — to DIN 557. Stocked across roughly M5 to M20, they cover general to heavy-duty work.
Typical Applications for Square Nuts
The most common settings where these are specified:
- Bolted joints: the clamping counter-face on studs and bolts across every assembly type.
- Vibration-prone equipment: where a locking or flanged style resists loosening.
- Frames & weldments: captive or welded options for repeatable assembly.
- Strut & channel systems: sliding into channel where the flats stop rotation.
- Woodworking: large-bearing nuts seated into timber.
How to Specify Square Nuts for Your Application
- Size: Match the nominal size to the mating thread or hole. This product spans M5–M20; check the full table below for the exact dimensions of each size.
- Locking & grade: Match the strength grade to the bolt, and choose a locking style (nyloc, all-metal, serrated flange) if the joint sees vibration.
- Environment: For damp, coastal or chemical exposure prefer A4/316 stainless or a suitable coating; indoors, plated steel or A2 is usually sufficient.
- Standard: This product is supplied to DIN 557. Quoting the standard on your order guarantees interchangeable dimensions between suppliers.
Where Square Nuts Are Not the Right Choice
Not on their own — they need a matching bolt or stud — and a plain nut is not a substitute for a locking type under heavy vibration.