Overview
ISO 4162:2012 - Hexagon bolts with flange (small series) defines the characteristics of hexagon flange bolts in product grade A while the driving feature is specified to product grade B. It covers bolts with metric threads M5 to M16 and property classes 8.8, 9.8, 10.9 (carbon/alloy steels) and A2‑70 (stainless steel). The standard provides dimensional tables, tolerances, gauging procedures and references to related mechanical and surface-finish requirements.
Key topics and technical requirements
- Scope and designation
- Applies to small-series hexagon flange bolts; designation examples are shown (e.g., “Hexagon flange bolt ISO 4162:-, M12 × 80 - 8.8”).
- Dimensions and geometry
- Detailed figures and Table 1 specify head, flange and shank dimensions (full shank and reduced shank types), underhead configurations (types F and U) and wrenching/heights.
- Threads and tolerances
- Threads follow ISO metric series and tolerances (references include ISO 261 and ISO 965‑2). Tolerance class for external threads is specified (e.g., 6g).
- Material and property classes
- Mechanical property references: ISO 898‑1 for carbon/alloy steels and ISO 3506‑1 for stainless steel (A2‑70).
- Surface finishes and coatings
- Electroplating and finish requirements referenced to ISO 4042, zinc‑flake coatings to ISO 10683, and stainless passivation to ISO 16048.
- Acceptance, surface integrity and inspection
- Gauging method (Annex A)
- Head gauging uses two ring gauges (A and B) to verify hexagon height, wrenching height, corner fill and width across corners.
Applications and users
- Typical applications: machinery, automotive assemblies, equipment manufacturing, and any assembly where flange-bearing hexagon bolts are required with controlled geometry and mechanical properties.
- Primary users:
- Fastener manufacturers and quality control engineers (dimensioning, gauging, production tolerances)
- Design and mechanical engineers (component selection and interchangeability)
- Procurement and purchasers (product specification and designation)
- Test and inspection labs (acceptance sampling and surface checks)
Related standards
ISO 4162:2012 is a practical, implementation-focused standard for consistent specification, manufacture and inspection of small‑series hexagon flange bolts - useful for designers, manufacturers and quality professionals needing interchangeability and reliable mechanical properties.