Material
Carbon Steel
Type
Flat washer, Form A (plain)
Size Range
M2–M64
Surface Finish
Zinc-Plated / Plain / H.D.G
Hardness
140 / 200 / 300 HV
Standard
DIN 125 A / ISO 7089
Packaging
Carton / Pallet
MOQ
1 piece (sample)
Precision Manufacturing, Batch After Batch
From cold-heading raw steel wire to heat-treated finished bolts, every step runs under strict in-house process control — ensuring the dimensional accuracy and strength grade printed on every head marking.
Product Overview
Application Scenarios
Flat washers (DIN 125 Form A / ISO 7089) are plain annular washers placed under a bolt head or nut to spread the clamping load over a larger area, protect the surface from marring, and bridge slightly oversized or slotted holes. By distributing the load they reduce the risk of the head or nut pulling into or crushing softer materials such as timber, plastic, aluminium and sheet metal. They are used in virtually every bolted assembly — structural steel, machinery, electrical panels, automotive, furniture and general fabrication. Stainless versions suit visible, damp, outdoor and food-contact applications.
Installation Notes
Select the washer size to match the bolt: the inner diameter (d1) clears the thread while the outer diameter (d2) spreads the load. On high-strength joints (grade 8.8 and above) use a hardened washer (200 HV / 300 HV) so the washer does not bite or dish under the bolt head. A flat washer spreads load but does not by itself lock a joint — pair it with a spring lock washer, a nylon-insert nut or a thread-locker where vibration is a concern. Match the washer finish and material to the bolt to avoid galvanic corrosion.
Material & Certification
Stamped from quality carbon steel strip to DIN 125 Form A / ISO 7089 and supplied plain or with 140–300 HV hardness for high-strength joints, with every batch traceable to raw material certificates. Each production lot passes 100% dimensional inspection (inner and outer diameter, thickness, flatness) before packaging; EN 10204 3.1 material certificates are available on request.
Flat Washer (Form A)
Carbon Steel Flat Washer · Form A · DIN 125 / ISO 7089
Dimensional Specifications
DIN 125 A / ISO 7089 Standard Reference Dimensions — click a size to locate it below
| Nominal Size | Inner Dia d1 (mm) | Outer Dia d2 (mm) | Thickness s (mm) |
|---|---|---|---|
| M6 | 6.4 | 12.5 | 1.6 |
| M8 | 8.4 | 17.0 | 1.6 |
| M10 | 10.5 | 21.0 | 2.0 |
| M12 | 13.0 | 24.0 | 2.5 |
| M16 | 17.0 | 30.0 | 3.0 |
| M20 | 21.0 | 37.0 | 3.0 |
| M24 | 25.0 | 44.0 | 4.0 |
Reference dimensions per DIN 125 A / ISO 7089 standard. Full size range M2–M64 available on request — contact us for custom specification sheets.
Applications
Construction
Steel structures, bridges, buildings, concrete anchors
Machinery
Heavy equipment, industrial machines, manufacturing
Infrastructure
Railways, towers, pipelines, power transmission
Automotive
Vehicle assembly, chassis, engine components
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