Hexagonal Flange Bolts

Hexagonal flange bolts are advanced fasteners where the hex head and wide, load-distributing flange are cold-forged as a single piece. The primary advantage of these bolts is the flange anti-slip effect provided by the integrated design, delivering excellent vibration resistance. Manufactured to ISO 1661 standards, the flange surface often includes serrated teeth that bite into the material, significantly increasing friction and enhancing anti-loosening performance compared to standard bolts. The one-piece construction ensures a secure connection with no risk of flange detachment. A smooth chamfer at the shank-flange junction prevents stress concentration. With 6g thread precision and shear strengths starting at grade 8.8, product is the optimal choice for high-vibration fastening applications.

Hexagonal flange bolts are widely used in automotive engines, transmissions, chassis systems, construction machinery, agricultural machinery, and electric motor assemblies. In engines, they secure cylinder heads and oil pans, withstanding high-temperature vibration to maintain sealing performance. Within automotive chassis, they are essential for suspension and braking systems, where their anti-loosening performance is critical for safety. In construction machinery such as excavators and loaders, they endure severe vibration and impact under harsh operating conditions. For agricultural machinery, they secure key components exposed to outdoor operating environments. In electric motors, they prevent end cap loosening caused by operational vibration. Product is a cornerstone of reliable mechanical design.

These bolts are manufactured from alloy steels (40Cr/35CrMo) or stainless steel 316. Alloy steels are heat-treated to grades 8.8 or 10.9, with grade 10.9 achieving HRC 32–36 hardness and tensile strength ≥1000 MPa. Stainless steel 316 provides excellent corrosion and high-temperature resistance for demanding environments. Surface treatments include black oxide (GB/T 15519), zinc plating (ASTM B633), and Dacromet coating (DIN 50961), offering 72–144 hours of salt spray resistance. Hexagonal flange bolts are certified to ISO 9001 and IATF 16949 standards, meeting rigorous automotive industry requirements. Custom options are available for oversized flanges, extended lengths (up to 300 mm), specialized serrated flange teeth, and finishes such as cadmium plating. Packaged 100–200 pieces per individually sealed pack with clear strength grade markings, these bolts are easy to select and ready for demanding applications.