Flange Slotted Nuts

Flange slotted nuts represent the pinnacle of anti-loosening design by combining two robust locking features in a single component. They merge the wide, serrated bearing surface of a flange nut with the positive mechanical lock of a slotted (castle) nut. This dual-action design makes flange slotted nuts the preferred choice for applications subjected to extreme vibration and shock, such as heavy-duty trucking, agricultural machinery, and critical aerospace assemblies, where failure is not an option.

The security of a flange slotted nut comes from redundancy. First, the integral flange has radially serrated teeth that bite into the mating surface upon tightening, creating strong frictional resistance to rotation. Second, once the correct torque is applied, the slots in the nut's crown align with a cross-drilled hole in the bolt. Inserting and bending a cotter pin provides a reliable mechanical backup, ensuring the nut cannot rotate under any condition.

These nuts are manufactured to exacting standards, often specified by OEMs or governing bodies like the FAA for aerospace use. They are typically made from high-strength alloy steel (e.g., 4140/4142), heat-treated to Grade 8 or 10, and may feature specialized surface treatments such as cadmium or zinc-nickel plating for corrosion protection. Our production process includes rigorous testing for hardness, torque-tension relationships, and slot alignment to guarantee performance.