Family · Nuts
Hex nuts, flange nuts and lock nuts, M5 – M30.
Nuts are cold-formed and tapped to DIN 934, ISO 4032, DIN 6923 and ISO 7040/7042, in classes 8 and 10, with hot-dip galvanized versions over-tapped to EN ISO 10684. Proof load is tested per ISO 898-2 on every lot.
DIN 6923
Hex Flange Nut
Flange nut with a serrated bearing face that spreads clamp load and resists loosening on thin sheet.
DIN 985
Nylon Insert Lock Nut
Prevailing-torque lock nut with a moulded nylon collar for vibration-prone joints. Reusable up to five cycles.
Specify it once
What to put on the drawing or the PO.
The four lines below decide whether the parts fit, hold and survive. Nine quoting delays out of ten are one of them missing.
- Nut class matched to the bolt: class 8 with 8.8, class 10 with 10.9 — an under-class nut strips before the bolt yields.
- Prevailing torque for lock nuts, and the number of reuses your assembly allows (ISO 7040/7042 test five).
- Over-tap allowance if the mating bolt is hot-dip galvanized, and whether the nut is centrifuged and re-tapped after coating.
- Style: standard hex, thin (DIN 439), flange (DIN 6923) or all-metal lock nut for hot or high-vibration joints.
Where it goes wrong
Mistakes we see on incoming drawings.
We will flag these before production rather than after the first inspection. If a mistake is already in the drawing, we say so in writing on the quote.
- Pairing a class 10.9 bolt with a class 8 nut, so the thread strips instead of the bolt stretching — a failure mode with no warning.
- Using a nylon-insert nut above roughly 120 °C, where the insert creeps and the prevailing torque disappears.
- Treating a thin nut (DIN 439) as a structural nut; it has fewer engaged threads and a lower proof load.
Common questions
Nuts — answered before you ask.
Something not covered? Email sales@ianzai.com and a person answers, usually inside a shift.
Which nut class goes with which bolt?
What is the temperature limit of a nylon insert lock nut?
Do hot-dip galvanized nuts fit hot-dip galvanized bolts?
Other families
What else leaves the same plant.
Next step
Send the standard number and the quantity.
You get unit price, MOQ, pack multiple, lead time and the Incoterm you buy on — within one business day, with the HS code for your broker.