Overview
Flange bolts are hex head bolts with an integrated washer-like flange beneath the head. The built-in flange distributes load over a larger surface area and helps eliminate the need for a separate washer.
Commonly used in automotive assembly, heavy equipment, structural steel, agricultural machinery, and industrial manufacturing, flange bolts provide secure fastening, vibration resistance, and faster installation.
Offshore Milling & Sourcing supports bulk and factory-direct sourcing programs for flange bolts, serving distributors, OEM manufacturers, equipment builders, and procurement teams requiring dependable high-volume supply and competitive pricing.
Types of Flange Bolts Available
- Standard Hex Flange Bolts
- Serrated Flange Bolts
- Non-Serrated Flange Bolts
- Metric Flange Bolts
- Structural Flange Bolts
- JIS Flange Bolts
- Automotive Spec Flange Bolts
- Custom Per-Print Flange Bolts
Specifications
- Diameter Range: 1/4″ – 1-1/2″ (Metric M5 – M24+)
- Length Range: 1/2″ – 12″+
- Thread Type: UNC / UNF / Metric Coarse / Metric Fine
- Flange Type: Serrated / Smooth
- Standards: SAE J429 / ASTM / DIN / ISO / JIS
Flange bolts are designed to provide built-in load distribution and secure clamping performance.
Grades Available
- Grade 2
- Grade 5
- Grade 8
- SAE J429
- ASTM A307
- ASTM A325 (structural applications)
- Metric Class 8.8 / 10.9 / 12.9
Grade selection depends on structural load requirements and application type.
Materials
- Low Carbon Steel
- Medium Carbon Steel
- Alloy Steel
- Stainless Steel 304
- Stainless Steel 316
- Hot Forged Structural Steel
- Specialty alloys upon request
Material choice is driven by strength, corrosion resistance, and environmental exposure.
Finish & Coating Options
- Zinc Plated
- Yellow Zinc
- Black Oxide
- Hot Dip Galvanized
- Mechanical Galvanized
- Plain Finish
- Stainless (Natural Finish)
- Zinc Flake Coating
- Custom corrosion-resistant coatings available
Serrated flange bolts are often specified where vibration resistance is required.
Industries Served
- Automotive Manufacturing
- Heavy Equipment
- Agricultural Equipment
- Structural Steel Fabrication
- Oil & Gas
- Construction
- OEM Manufacturing
- Industrial Distribution
Applications
- Engine assembly
- Suspension systems
- Structural steel connections
- Agricultural machinery
- Industrial equipment
- Equipment mounting systems
Flange bolts are ideal where washer elimination improves assembly efficiency and reduces part count.
Strategic Bulk Sourcing Programs
Flange bolts are one of the most commonly imported industrial bolt categories due to recurring OEM demand and automotive volume requirements.
We support:
- Factory-direct container programs
- Mixed SKU consolidation
- Secondary sourcing strategies
- Blanket purchase agreements
- Custom forging programs
- Automotive-grade manufacturing
- Private label packaging
Our sourcing programs are structured for distributors and OEMs seeking scalable capacity and long-term supply stability.
Packaging Options
- Bulk cartons
- Palletized shipments
- Gaylord containers
- Custom-labeled packaging
- OEM packaging
- Mixed container programs
Request a Quote
To receive pricing for flange bolts, please provide:
- Diameter
- Length
- Grade
- Flange type (serrated or smooth)
- Finish
- Quantity
- Delivery timeline
Engineering drawings may be included for custom parts.
