Application guide for Left-Hand Thread Hex Nuts to DIN 934. The core duty of the type is the clamped counter-face of a bolted joint. The typical industries, the how-to-specify checklist, assembly practice and the exclusion cases are set out below. Stocked across roughly M6 to M24, they cover general to heavy-duty work.
Typical Applications for Left-Hand Thread Hex Nuts
The most common settings where these are specified:
- Fabrication & metalwork: bench and on-site assembly of steel frames, enclosures and weldments.
- 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.
- General machine building: fastening covers, brackets, motors and sub-assemblies on production equipment.
How to Specify Left-Hand Thread Hex Nuts for Your Application
- Size: Match the nominal size to the mating thread or hole. This product spans M6–M24; 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 934. Quoting the standard on your order guarantees interchangeable dimensions between suppliers.
Installation & Assembly Practice
- Run the nut down by hand before applying the wrench to catch cross-threading early.
- Tighten the nut rather than the bolt head where access allows — the torque-to-preload relation is more consistent.
- For locking styles, note that nyloc inserts are single-use in critical joints and lose grip above roughly 120 °C.
Common Selection Mistakes with Left-Hand Thread Hex Nuts
- Pairing a high-class bolt with a lower-class nut — the nut strips before the bolt reaches proof load; the nut class must meet or exceed the bolt class.
- Using a plain nut with a spring washer in severe vibration instead of a prevailing-torque locking nut.
- Re-using nyloc nuts in critical joints.
Where Left-Hand Thread Hex 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.
Custom manufacturing · Made to drawing
Need a left-hand thread hex nuts outside the standard range?
Thread, height, across-flats, property class, locking feature and flange form can all be varied, including thread sizes the standard series does not run to. Made by cold heading or tapping.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.

