For tab lock washer for round nut, T 858 defines the dimensions, tolerances and product grades. The sections below describe the scope of the document, the properties it deliberately leaves to companion standards, and the equivalent designations across standards bodies.
T 858 — Scope
T 858 specifies the dimensions and tolerances of tab lock washer for round nut — gb/t 858 (series 072). 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
T 858, alongside the related GB/T 858 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 T 858
| For shaft / nut size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Thickness t (mm) | Tab length (mm) | Reference standard |
|---|---|---|---|---|---|
| M10 | 10.5 | 21 | 1.0 | 8 | GB/T 858 |
| M12 | 12.5 | 25 | 1.0 | 9 | GB/T 858 |
| M16 | 16.5 | 30 | 1.0 | 10 | GB/T 858 |
| M20 | 20.5 | 38 | 1.5 | 12 | GB/T 858 |
| M24 | 24.5 | 45 | 1.5 | 14 | GB/T 858 |
| M30 | 30.5 | 55 | 1.5 | 16 | GB/T 858 |
| M36 | 36.5 | 65 | 2.0 | 18 | GB/T 858 |
| M48 | 48.5 | 85 | 2.0 | 20 | GB/T 858 |
| M60 | 60.5 | 105 | 2.5 | 24 | GB/T 858 |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent Tab Lock Washer for Round Nut — GB/T 858 (Series 072) page. Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
Companion Standards
T 858 controls only the geometry of tab lock washer for round nut — gb/t 858 (series 072). 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).