Fender Washers manufactured to DIN 9021 follow a specific scope. This page summarizes that scope, lists every dimension the standard fixes, and points to the most common cross-references.
DIN 9021 — Scope
DIN 9021 specifies the dimensions and tolerances of fender washers. Material, property class, surface finish and packaging are governed by separate documents in the same standards family (for example ISO 898-1 for the mechanical property classes of bolts and screws).
Tolerance & Product Grades
DIN 9021, alongside the related DIN 9021 entries on this site, specifies product grades (typically A or B for fine work and C for general engineering) and tolerance classes for the controlling dimensions. Choose the grade against the precision your application requires.
Dimensions Specified by DIN 9021
| For bolt size | Inner diameter d1 min (mm) | Outer diameter d2 max (mm) | Thickness h (mm) | Reference standard | Notes |
|---|---|---|---|---|---|
| M3 | 3.2 | 9.0 | 0.8 | DIN 9021 / ISO 7093 | Oversized OD for bearing on soft materials |
| M4 | 4.3 | 12.0 | 1.0 | DIN 9021 / ISO 7093 | Oversized OD for bearing on soft materials |
| M5 | 5.3 | 15.0 | 1.2 | DIN 9021 / ISO 7093 | Oversized OD for bearing on soft materials |
| M6 | 6.4 | 18.0 | 1.6 | DIN 9021 / ISO 7093 | Oversized OD for bearing on soft materials |
| M8 | 8.4 | 24.0 | 2.0 | DIN 9021 / ISO 7093 | Oversized OD for bearing on soft materials |
| M10 | 10.5 | 30.0 | 2.5 | DIN 9021 / ISO 7093 | Oversized OD for bearing on soft materials |
| M12 | 13.0 | 37.0 | 3.0 | DIN 9021 / ISO 7093 | Oversized OD for bearing on soft materials |
| M14 | 15.0 | 44.0 | 3.0 | DIN 9021 / ISO 7093 | Oversized OD for bearing on soft materials |
| M16 | 17.0 | 50.0 | 3.0 | DIN 9021 / ISO 7093 | Oversized OD for bearing on soft materials |
| M20 | 21.0 | 60.0 | 4.0 | DIN 9021 / ISO 7093 | Oversized OD for bearing on soft materials |
| M24 | 25.0 | 72.0 | 5.0 | DIN 9021 / ISO 7093 | Oversized OD for bearing on soft materials |
| M30 | 31.0 | 90.0 | 6.0 | DIN 9021 / ISO 7093 | Oversized OD for bearing on soft materials |
| M36 | 37.0 | 110.0 | 8.0 | DIN 9021 / ISO 7093 | Oversized OD for bearing on soft materials |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent Fender Washers page. Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
Companion Standards
DIN 9021 controls only the geometry of fender washers. The mechanical strength is set by ISO 898-1 (bolts and screws) or ISO 898-2 (nuts); the surface finish is governed by separate finish standards (e.g. ISO 4042 for electroplating). For corrosion testing, the relevant document is ISO 9227 (neutral salt spray).