Overview
ISO 15071:2011 - "Hexagon bolts with flange - Small series - Product grade A" specifies the characteristics, dimensions and acceptance criteria for hexagon flange bolts in small series. The standard covers metric threads from M5 to M16 and applies to bolts in property classes 8.8, 9.8, 10.9 and A2‑70. It is part of ISO’s family of external hexagon fastener product standards and replaces the 1999 edition (with corrigendum).
Key Topics
- Scope & product grade: Small-series hexagon flange bolts, Product grade A, thread sizes M5–M16, specified property classes.
- Dimensions & profiles: Detailed dimensional data, head and flange geometry, and shank types (standard, reduced shank, with/without undercut) shown in Figures 1–3 and Table 1.
- Threads & tolerances: Threads per ISO 261 and tolerances per ISO 965‑2 and tolerance class 6g.
- Mechanical properties: Steel bolts per ISO 898‑1; corrosion‑resistant bolts per ISO 3506‑1.
- Surface finish & coatings: Electroplating requirements (ISO 4042) and non‑electrolytic zinc‑flake coatings (ISO 10683); additional finishes by agreement.
- Surface integrity & inspection: Limits for surface discontinuities (ISO 6157‑3) and acceptance inspection procedures (ISO 3269).
- Gauging & acceptance: Normative Annex A describes a two‑ring gauging method for head geometry and a gauge for flange thickness; examples for designation and gauging tolerances are provided.
- Designation examples: e.g., Hexagon bolt with flange ISO 15071 - M12 × 80 - 8.8 (or include type letter F/U/R).
Applications
ISO 15071:2011 is used by:
- Fastener manufacturers and OEMs to produce bolts to a recognized international specification.
- Design and mechanical engineers specifying reliable hexagon flange bolts for assemblies requiring known mechanical properties.
- Quality inspectors and procurement teams for acceptance testing, gauging and supplier verification.
Typical uses include general engineering and machine assembly where standardized flange head bolts with defined strength and corrosion options are required.
Related Standards
Relevant referenced and related standards include:
ISO 15071:2011 is an essential fastener standard for consistent specification, production, inspection and procurement of hexagon bolts with flange in small series production.