Metric Serrated Hex Flange Nuts – Carbon Steel M3–M24
Zinc-plated and black-finish serrated flange nuts for industrial machinery, OEM assembly and bulk fastener sourcing.
DISLAB PRECISION supports international B2B buyers with metric serrated hex flange nuts featuring an integrated flange, serrated underside and external hex drive. Select from two reference series or request specification-based sourcing.
- M3–M24 combined reference range
- Zinc-plated & black-finish series
- Flanged, serrated bearing surface
- Bulk supply & drawing-based inquiries
B2B only · Minimum order value USD 300 · Specification confirmation before ordering
Serrated Hex Flange Nuts for Secure Industrial Assembly
A serrated hex flange nut is a female-threaded hexagonal fastener with an integral, washer-like flange and small radial teeth on its bearing face. When correctly installed against a suitable mating surface, the teeth help resist relative rotation while the flange spreads contact across a wider bearing area than a conventional hex nut.
This design can simplify fastening where a separate flat washer would otherwise be used. Joint performance still depends on the bolt, material, preload, contact surface, torque method and service conditions. Serrated flange nuts are not universally suitable for painted, delicate or soft surfaces because the teeth can mark the mating material.
What Makes This Nut Different?
Serrated underside: helps increase rotational resistance at an appropriate contact surface.
Integral flange: offers a broader bearing face and may eliminate a separate flat washer in compatible joints.
External hex drive: installs with a suitable wrench or socket, subject to the actual across-flats dimension.
Practical Benefits for Production and Procurement
Integrated Flange
The broad flange face reduces part count in assemblies designed without a separate flat washer, potentially simplifying installation and kitting.
Serrated Grip
Underside serrations increase resistance to rotation on compatible surfaces; fastening reliability must still be assessed for the actual joint.
Two Reference Finishes
Compare dimensions from a zinc-plated carbon-steel series and a black-finish carbon-steel series. Exact coating processes and corrosion performance require confirmation.
Multi-Size B2B Sourcing
Provide several thread sizes and required quantities in one inquiry. We can review specifications, finishes and repeat-order purchasing requirements.
General Product Specifications
| Product type | Metric serrated hex flange nut |
|---|---|
| Other trade names | Serrated flange nut; hex flange lock nut; flanged hex nut with serrations |
| Material | Carbon steel; exact grade / nut property class subject to confirmation |
| Reference sizes | M3–M24 across two separate dimensional series |
| Threads | Metric coarse pitch as listed below |
| Body | External hex with integral serrated flange |
| Reference finishes | Zinc-plated series; black-finish series (coating details unverified) |
| Dimensional standard | Verify against the selected drawing; no blanket DIN 6923 conformance claim |
| Supply | Industrial bulk / OEM inquiries; USD 300 minimum order value |
Engineering note: The supplier references use bolt-like labels such as “8.8” and “10.9” for some material variants. Do not treat these as verified nut property classes. Specify the required nut grade and request documentation before a strength-critical purchase.
Metric Serrated Hex Flange Nut Size Charts
These two charts reproduce the supplied supplier-measured reference dimensions. They are separated intentionally: a zinc-plated M8 nut and black-finish M8 nut, for example, may have different outer dimensions. The values are not guaranteed tolerances or certified standard sizes.
Series A — Zinc-Plated Carbon Steel (M3–M20)
Swipe horizontally to see every dimension →
| Thread (d) | Pitch (P) | Height (m) | Flange OD (dc) | Across Flats (s) | Wrench (mm) |
|---|---|---|---|---|---|
| M3 | 0.50 | 3.60 | 7.5 | 5.5 | 5.5 |
| M4 | 0.70 | 4.40 | 8.9 | 7.0 | 7 |
| M5 | 0.80 | 4.70 | 10.6 | 8.0 | 8 |
| M6 | 1.00 | 5.40 | 13.0 | 9.6 | 10 |
| M8 | 1.25 | 6.35 | 16.2 | 12.0 | 12 |
| M10 | 1.50 | 7.82 | 18.9 | 14.0 | 14 |
| M12 | 1.75 | 10.20 | 23.4 | 17.8 | 18 |
| M14 | 2.00 | 12.50 | 28.3 | 21.0 | 21 |
| M16 | 2.00 | 13.50 | 32.0 | 24.0 | 24 |
| M18 | 2.50 | 15.40 | 36.0 | 27.0 | 27 |
| M20 | 2.50 | 16.20 | 39.4 | 30.0 | 30 |
Series A is based on supplied sampled-batch dimensional information. Availability and tolerance acceptance are confirmed at quotation.
Series B — Black-Finish Carbon Steel (M4–M24)
Swipe horizontally to see every dimension →
| Thread (d) | Pitch (P) | Height (m) | Flange OD (dc) | Across Flats (s) | Wrench (mm) |
|---|---|---|---|---|---|
| M4 | 0.70 | 3.70 | 9.1 | 7.0 | 7 |
| M5 | 0.80 | 4.80 | 10.5 | 7.8 | 8 |
| M6 | 1.00 | 5.40 | 13.0 | 10.0 | 10 |
| M8 | 1.25 | 7.00 | 16.4 | 12.9 | 13 |
| M10 | 1.50 | 8.60 | 21.0 | 15.0 | 15 |
| M12 | 1.75 | 9.90 | 25.0 | 18.0 | 18 |
| M14 | 2.00 | 13.30 | 29.3 | 20.7 | 21 |
| M16 | 2.00 | 13.60 | 31.3 | 23.7 | 24 |
| M18 | 2.50 | 18.00 | 38.3 | 27.0 | 27 |
| M20 | 2.50 | 19.00 | 41.7 | 30.0 | 30 |
| M24 | 3.00 | 22.00 | 45.8 | 36.0 | 36 |
Series B is based on supplied sampled-batch dimensions. “Black-finish” does not certify a particular coating process or corrosion resistance.
Dimension Symbols
d — nominal thread diameter
P — thread pitch
m — overall nut height
dc — flange outside diameter
s — hexagon width across flats
Wrench: nominal opening shown in the supplier reference, not a dimensional tolerance. For tight clearances, verify actual across-flats size.
M8 example: The zinc-plated reference specifies a 6.35 mm height, 16.2 mm flange OD and 12.0 mm across-flats width, while the black-finish reference specifies 7.00 mm, 16.4 mm and 12.9 mm respectively. Do not assume interchangeability by thread size alone.
How to Specify the Correct Serrated Flange Nut
1. Match Diameter and Pitch
Confirm the mating bolt or stud. For example, M8 × 1.25 means an 8 mm nominal metric thread and 1.25 mm pitch.
2. Check Flange Clearance
Review the actual flange outside diameter and surrounding clearances, including proximity to nearby parts.
3. Verify Height and Tool Fit
Confirm overall nut height, across-flats dimension and wrench or socket clearance before ordering.
4. Specify Strength and Finish
Supply required nut property class, bolt property class, coating details, service environment and inspection requirements.
5. Review Contact Surfaces
Serrations can mark coated, soft or delicate surfaces. Choose the appropriate fastening design for the material.
6. Confirm Assembly Conditions
Define torque/preload requirements and vibration or service conditions; validate important joints in the actual assembly.
Common Uses for Serrated Hex Flange Nuts
Typical sourcing inquiries involve industrial machinery, fabricated metal frames, equipment brackets, maintenance spares, selected automotive accessories and OEM mechanical assemblies. Suitability must be determined by the application’s mechanical and material requirements.
- Industrial machinery: brackets, guards and equipment housings.
- Metal fabrication: compatible steel assemblies and mounting parts.
- Equipment maintenance: metric replacement hardware and spare-parts sourcing.
- OEM programs: assembly BOM sourcing, multi-size supply and specified finishes.
- Distributors: industrial quantities and packaging requirements.
Bulk Orders, OEM Requirements and International Supply
DISLAB PRECISION works with overseas industrial buyers, hardware distributors and equipment manufacturers. Customers can request several metric sizes, specified finishes, drawing-based external dimensions, repeat purchasing arrangements and packaging requirements in one RFQ.
Material certificates, nut property classes, dimensional tolerances, coating specifications, inspection documents and production lead times are subject to technical and commercial confirmation. Custom configurations are reviewed case by case.
B2B only · Minimum order value USD 300 · Availability and production details confirmed by quotation
Serrated Hex Flange Nut FAQ
What is a serrated hex flange nut?
It is an internally threaded hexagonal nut with an integrated flange and serrations on the flange’s bearing surface. The teeth help resist rotation against a suitable mating surface.
How is it different from a regular hex nut?
A regular hex nut generally lacks the integrated flange and serrated bearing surface. A serrated flange nut provides a wider bearing area and additional grip where the teeth engage the mating material.
Do serrated flange nuts always replace washers?
No. An integral flange can remove the need for a separate flat washer in some suitable designs, but the joint specification, contact material and required hardware determine whether a washer is needed.
Are these products compliant with DIN 6923?
DIN 6923 is a commonly referenced standard for hexagon flange nuts. The supplied product tables include dimensions that may differ from standard dimensions. Confirm conformance for the exact product and purchase specification rather than assuming all listed references comply.
What metric thread sizes are covered?
The supplied zinc-plated dimensional series covers M3–M20, while the black-finish series covers M4–M24. Exact size and finish availability is confirmed when quoting.
Can serrated flange nuts be used on painted or soft surfaces?
The serrations can mark or damage painted, plated, soft or delicate materials. Review the joint requirements and consider a non-serrated fastener where surface protection is important.
Can I specify a nut strength class or coating?
Yes. Send the required nut property class, material specification, surface finish, inspection requirements and quantity. DISLAB PRECISION will review sourcing feasibility and documentation requirements.
What information is needed for a fast bulk quotation?
Provide thread size and pitch, selected series or drawing, finish, required mechanical properties, quantity, destination country and any packaging or test requirements.
Request a Quote
Direct Contact Channels
- Thread size, finish, dimensions and application requirements reviewed with your inquiry
- Bulk and OEM quotation support for industrial buyers, distributors and equipment builders