ISO 4014 Hex Head Bolt

About ISO 4014 Hex Head Bolt

The Stainless Steel ISO 4014 Hex Head Bolt is a globally standardized, premium-grade fastener featuring a six-sided hexagonal head and a partially threaded shank. Governed by the International Organization for Standardization, the ISO 4014 standard defines strict dimensional profiles and mechanical tolerances, serving as the modern global successor to the older German DIN 931 standard. Designed with an unthreaded smooth section (shank) directly beneath the head, this bolt delivers superior shear strength, precision alignment, and heavy clamping force in critical joint assemblies.

Key Features & Design

• Partially Threaded Shank: Features a smooth, unthreaded mid-section that handles high lateral shear forces without the stress concentration points found in threaded areas.

• Hexagonal Drive Profile: Designed for maximum torque application using standard industrial wrenches, impact drivers, or socket systems.

• Global Product Grading: Divided strictly by strict tolerances into Product Grade A (for tight fits in sizes up to M24 and lengths under 150mm) and Product Grade B (for larger or longer configurations).

• Clean & Hygienic Finish: Built from premium stainless steel, providing a bright surface finish that requires no additional anti-rust coatings and prevents aesthetic rust-bleeding.

Material Grades & Specifications

ISO 4014 bolts are typically cold-worked and processed to maximize mechanical load capacities according to global fastener requirements like ISO 3506-1:

• A2 Stainless Steel (Grade 304): The most widely specified standard. Composed of an 18/8 Chromium-Nickel matrix, it guarantees superior oxidation resistance in standard environments, urban structures, and regular moisture exposure.

• A4 Stainless Steel (Grade 316): Marine-grade engineering standard. Fortified with Molybdenum to actively resist pitting, crevice corrosion, and chloride cracking in heavy chemical, industrial, and offshore maritime setups.

• Property Class: Most frequently cold-formed to Class 70 (A2-70 or A4-70), certifying a baseline tensile strength of 700 MPa.

ISO 4014 vs. DIN 931 Dimensional Differences

While ISO 4014 directly replaces DIN 931, engineers must note slight variations in the Width Across Flats (WAF / wrench size) for specific metric nominal diameters:

• M10 Diameter: ISO 4014 utilizes a 16 mm WAF (reduced from the DIN 931 standard of 17 mm).

• M12 Diameter: ISO 4014 utilizes an 18 mm WAF (reduced from the DIN 931 standard of 19 mm).

• M14 Diameter: ISO 4014 utilizes a 21 mm WAF (reduced from the DIN 931 standard of 22 mm).

• M22 Diameter: ISO 4014 utilizes a 34 mm WAF (increased from the DIN 931 standard of 32 mm).

Technical Parameters

• Size Range: Extends comprehensively across metric diameters from M1.6 up to M64.

• Thread Fitting: Machined precisely to metric coarse thread pitches matching a standard 6g thread tolerance class.

• Thread Length Calculation: Regulated uniformly based on size thresholds to match modern mating requirements.

Target Applications & Industries

Thanks to their rigorous international compliance, these bolts are relied upon heavily in transnational engineering:

• Civil Infrastructure: Long-term structural joints in steel bridges, multi-story frameworks, and stadium roofs.

• Renewable Energy: Assembly of heavy-duty wind turbine bases, solar racking structures, and coastal tidal power arrays.

• Process Industries: Secure heavy flange connections on high-pressure pipelines in oil, gas, and chemical processing networks.

• Specialist Environments: Medical and food-grade machinery requiring non-magnetic, highly sterile, and easy-to-clean structural fasteners.