DIN 125 · ISO 7089
Flat Washer
Hardness-controlled flat washer, 200 HV, for distributing clamp load under bolts and nuts.
From
$0.0078/pc
at 500,000 pcs
Specs
Family · Washers
Flat, spring and structural washers, M5 – M30.
Washers are punched or fine-blanked to DIN 125, DIN 127, DIN 6902 – 6906 and DIN 6916/6917, with hardness specified per series. Flat washers carry a load; spring washers take up settlement; neither is a locking device on its own.
DIN 127
Spring Washer
Heat-treated 65Mn spring washer that keeps preload on joints exposed to vibration and thermal cycling.
From
$0.0095/pc
at 400,000 pcs
Specs
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.
- Series and hardness: 140 HV or 200 HV flat washers, 44 – 50 HRC spring washers, 300 HV structural washers to EN 14399-6.
- Inside and outside diameter with tolerance, not just nominal size — plating build-up changes the ID.
- Coating matched to the bolt, including the same salt-spray class, or the washer becomes the corrosion site.
- Whether the application needs a hardened washer under a 10.9 bolt, where a soft washer will collapse and lose preload.
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.
- Counting a spring washer as a lock. It resists settlement; it does not stop a joint loosening under vibration.
- Using a 140 HV washer under a 10.9 bolt — the washer deforms and preload disappears within days.
- Mixing coating systems on bolt and washer, so the pair fails at the washer edge.
Common questions
Washers — answered before you ask.
Something not covered? Email sales@ianzai.com and a person answers, usually inside a shift.
Does a spring washer actually lock a joint?
No — and it is worth saying plainly. It stores a little energy and takes up settlement, but ISO 898 does not treat it as a locking element. For vibration, use a lock nut, a threadlocker or a properly preloaded joint.
Which washer for an M12 class 8.8 bolt?
DIN 125 A, 200 HV, matching the bolt coating. If the joint is preloaded to the bolt limit, use a hardened washer to EN 14399-6 instead.
Do you make square, taper and anti-vibration washers?
Yes — DIN 434/435 taper washers for channel and I-beam flanges, DIN 436 square washers for timber, and ribbed flange washers. Square and taper are quoted from drawing or standard.
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.