When to use flange hex bolts and when to use ordinary hex bolts?

When to use hex flange bolt?

Worried about screws loosening (such as places where cars and machines vibrate a lot) → The serrations or knurling on the flange surface can bite the parts and are not easy to loosen.

Worried about crushing parts (such as soft materials such as plastics and aluminum alloys) → Flange gaskets can disperse pressure and avoid dents.

Too lazy to install gaskets → Flange bolts come with washers, which saves trouble.

Need to seal (such as water pipes and oil pipe joints) → The flange surface can be pressed tighter to reduce leakage.

When to use ordinary hex bolt?

No worries about loosening (such as fixed structures that do not vibrate) → Ordinary bolts are enough.

Limited space (flange bolt heads are larger and may not fit) → Ordinary bolts are more compact.

Already have gaskets (such as spring washers, flat washers) → No need to bring your own flange.

Cost considerations → Ordinary bolts are generally cheaper and can save money when used in large quantities.

Summary in one sentence
To prevent loosening, crushing and save trouble → choose flange hexagon bolts (such as cars, machines and pipes).
To prevent loosening, small space and save money → choose ordinary hexagon bolts (such as furniture and ordinary steel structures).