Overview
EN ISO 8675:2023 - Fasteners: Hexagon thin nuts (style 0) with fine pitch thread - specifies the characteristics, dimensions and product requirements for hexagon thin nuts manufactured in steel and stainless steel. The standard covers metric fine‑pitch thread sizes from 8 mm to 64 mm, and defines product grades A and B. These thin nuts (style 0) are intended for use as jam nuts assembled together with a regular or high nut.
Important warning: thin nuts (style 0) have reduced loadability compared to regular or high nuts and are not designed to provide resistance to thread stripping (see ISO 898‑2).
Key topics and technical requirements
- Scope & sizes: metric fine pitch thread range 8 mm - 64 mm; detailed dimensions for 8–39 mm in main tables and for D > 39 mm in normative Annex A.
- Materials & property classes: steel (quenched & tempered where applicable per ISO 898‑2) and stainless steel (common grades A2, A4; additional grades D4/D6 and property class 040 included). Stainless steel grades and property classes can be selected from ISO 3506‑2 where needed.
- Product grades: A and B (with product grade limits defined in the standard).
- Thread and tolerance: thread tolerance class 6H and general thread tolerancing per ISO 965‑1.
- Dimensions & drawings: hexagon thin nut geometry and dimensional tables (Figure 1, Tables 1–2).
- Surface, coatings & finishes: as processed (steel) or clean & bright (stainless); electroplated coatings per ISO 4042 or zinc‑flake per ISO 10683; surface discontinuities per ISO 6157‑2.
- Inspection, marking and labelling: acceptance inspection per ISO 3269; product marking per ISO 898‑2 (steel) and ISO 3506‑2 (stainless); package labelling requirements (ISO reference, thread size D×P, property class or grade, finish, lot number, quantity).
- Designation: follows ISO 8991 designation rules with property-class/grade identifiers.
Applications and who uses this standard
- Engineers and designers specifying jam nuts or space‑constrained assemblies where a thinner nut is required.
- Fastener manufacturers and distributors producing or supplying hexagon thin nuts (style 0) to ensure conformity with European and international requirements (EN/ISO).
- Procurement, quality and inspection teams using the standard for acceptance inspection, marking, labelling and traceability.
- Maintenance, automotive, machinery, and general mechanical applications where fine‑pitch metric threads and reduced nut thickness are desirable.
Related standards (for compliance and detail)
EN ISO 8675:2023 is the current CEN‑adopted version (approved June 2023) and supersedes EN ISO 8675:2012. Use this standard when specifying, manufacturing or inspecting metric hexagon thin nuts for reliable, standards‑based procurement and design.