Hex flange bolts have a hex head with a built-in round flange underneath. The flange spreads the load like a washer, so no separate washer is needed, and a serrated flange bites into the surface to resist loosening under vibration.
Linkworld supplies hex flange bolts from M5 to M20 in carbon steel, alloy steel and stainless steel, with serrated or plain flanges and zinc plated, black or plain finishes. They can be made to DIN 6921, DIN EN 1665, ISO 4162 or your drawing, and we pack in bulk cartons or in your own branded packs.
Hex Flange Bolt Specifications
| Specification | Configuration |
|---|---|
| Product | Hex flange bolt, serrated or plain flange |
| Thread sizes | M5 to M20 |
| Standards | DIN 6921, DIN EN 1665, ISO 4162 or drawing |
| Material | Carbon steel; alloy steel class 8.8 or 10.9; stainless steel |
| Finish | Zinc plated, black or plain |
| Thread | Metric coarse; fine thread on request |
| Packing | Bulk cartons, own-brand boxes, buckets and small packs |
Other sizes and finishes can be made to drawing or sample.
Where Hex Flange Bolts Are Used
- Vehicles and trailers body, chassis and bracket fixings
- Machinery covers, guards and frames under vibration
- Sheet metal where a separate washer is awkward to fit
- Steel framing and racking assembly bolts
Serrated or Plain Flange
- Serrated flange: resists loosening under vibration, but marks the surface. Avoid it on painted or soft parts.
- Plain flange: protects coated surfaces and suits parts that are taken apart.
- Strength class: 8.8 for general high tensile use, 10.9 for higher loads.
- Standard: DIN 6921 drawings are still common; DIN EN 1665 and ISO 4162 are the current versions.
Common Purchasing Mistakes
Not stating serrated or plain. They look similar in a carton but behave differently. State which one you need.
Assuming standards match. DIN 6921, DIN EN 1665 and ISO 4162 bolts are close but not identical. Quote the standard on your drawing.
Leaving out the strength class. Put 8.8 or 10.9 on every order line and label.
Serrated bolts on painted parts. The serrations damage coatings. Use a plain flange there.
What to Send with Your Enquiry
| Item | What to tell us |
|---|---|
| Size | Diameter and length |
| Flange | Serrated or plain |
| Standard | DIN, ISO or drawing |
| Material and class | 8.8, 10.9 or stainless |
| Finish | Zinc, black or plain |
| Quantity | Quantity for each size |
| Packing | Bulk carton, own-brand box or small pack |
| Destination | Destination port |
Packing and Supply for Distributors
We pack flange bolts in bulk cartons for trade distribution, or in your own branded boxes, buckets and small packs for retail. Each size can carry its own label. For customers who plan several deliveries through the year, we offer free warehouse storage and staged shipments.
Work With Linkworld
Linkworld has more than 20 years of fastener export experience and runs its own cold heading workshop. Our own QC team checks head, flange, thread and coating in our inspection room before every shipment. We make bolts to standard or drawing, so special lengths and flange types are welcome.
Frequently Asked Questions
What is a hex flange bolt?
It is a hex head bolt with a built-in flange that works like a washer.
What is the difference between serrated and plain flange bolts?
Serrated flanges grip the surface to resist loosening; plain flanges protect coated surfaces.
What sizes do you supply?
M5 to M20. Other sizes can be made to drawing.
Do you make flange bolts to DIN 6921?
Yes. We make them to DIN 6921, DIN EN 1665, ISO 4162 or your drawing.
Are stainless hex flange bolts available?
Yes. We supply stainless steel hex flange bolts as well as carbon and alloy steel.
Looking for hex flange bolts in your own sizes or packs?
Send the sizes, finish, quantity and packing you need through the enquiry form below, and our team will reply with the options that fit your range.
Send an Enquiry
Send a drawing, sample or clear reference photo. Add the quantity and application if available, and we can start from the information you already have.