Flanged Nuts

Flanged Nuts — Hex Flange & Serrated Flange Nuts

Flanged nuts incorporate an integral bearing washer into the nut body — providing load distribution without a separate washer and reducing part count in assembly. AIMS Industrial sells hex flange nuts and serrated flange nuts in metric Grade 8 and Grade 10 for automotive, agricultural, machinery, and structural fastening applications where washer integration is preferred.

Flanged Nuts We Stock

• Hex Flange Nuts — Plain Bearing: Smooth-flange hex nuts (ISO 4161) for applications requiring load distribution over a larger bearing area without the locking action of serrations. The smooth flange seats evenly on flat surfaces — preferred for precision assemblies where flange serrations would damage a finished surface.
• Serrated Flange Nuts: Serrated flange nuts have radial serrations on the flange face that bite into the mating surface — providing a self-locking action that prevents vibration loosening without a separate lock washer. Widely used in automotive, agricultural machinery, and transport equipment subject to vibration.
• Grade 8 (Grade 8 Property Class): Metric flange nuts matched to Grade 8.8 or 10.9 bolts for general structural and machinery fastening. Ensure the nut property class matches or exceeds the bolt grade for the assembly.
• Metric Size Range M6 to M20: Hex flange nuts available from M6 (light machinery and enclosures) through M12 (standard automotive and agricultural) to M20 (heavy structural applications).

Flanged Nut Application Guide

• When to Use Flange Nuts: Flanged nuts are preferred where (a) a separate washer would be lost or difficult to install during assembly, (b) the assembly is subject to vibration requiring positive locking (serrated type), or (c) the bearing surface area of a standard hex nut is insufficient for the joint material.
• Serrated vs Smooth Flange — Surface Compatibility: Serrated flange nuts damage painted, anodised, and coated surfaces. Use plain flange nuts on finished surfaces and serrated flange nuts on bare metal where the locking action is required. Serrations that score through a corrosion-resistant coating can initiate corrosion at the fastener seat.
• Reuse of Serrated Flange Nuts: The serrated flange nut self-locking action is partly provided by the first seating of serrations into the mating surface. Reinstalling a used serrated flange nut in the same position provides reduced locking performance — consider replacing serrated flange nuts on re-assembly of safety-critical joints.

Australian Business, Local Supply: As a proudly Australian business since 1988, we stock locally and work with trusted local Australian manufacturers and distributors to ensure fast, reliable supply.

Expert Support: Need help buying the right product for your application? Contact our team for application-specific advice or request a quote.

See our full fasteners range including hex head flanged bolts, hex lock nuts, and lock washers.