+86 (0) 159 5016 9967
sales@fullerkr.com
FULLERKREG DIN 929 hexagon weld nuts in 10B21 boron-alloyed medium-strength carbon steel at ISO Class 8 offer a cost-effective, high-performance solution for automotive, appliance, sheet-metal, and general structural weld assemblies. Manufactured to the DIN 929 standard, each nut features three symmetrically arranged welding projections on the bearing face that collapse and fuse with the base material during resistance welding, creating a flush, permanent, high-strength joint. The bare (uncoated) surface finish is the standard delivery condition for applications where post-weld painting, powder coating, e-coating, or zinc plating will be applied by the customer. ISO Class 8 provides a well-balanced combination of strength and ductility, making it the most widely specified carbon steel class for general-purpose weld nuts. Available in thread sizes M3 through M16.
All dimensions in mm. Tolerances per DIN 929. Unit weight (g) is theoretical reference value for carbon steel (density 7.85 g/cm³).
| Thread d |
Pitch (mm) |
Nut Height m (h14) |
Across Flats s (h13) |
Across Corners e (min) |
Spigot Dia. d2 (tol d11) |
Spigot Proj. h1 (tol) |
Weld Proj. h2 (tol) |
Unit Weight (g/pc) |
|---|---|---|---|---|---|---|---|---|
| M3 | 0.5 | 3.00 | 7.50 | 8.27 | 4.50 | 0.55 ±0.1 | 0.25 +0/-0.1 | ~0.9 |
| M4 | 0.7 | 3.50 | 9.00 | 9.91 | 6.00 | 0.65 ±0.1 | 0.35 +0/-0.1 | ~1.6 |
| M5 | 0.8 | 4.00 | 10.00 | 11.05 | 7.00 | 0.70 ±0.1 | 0.40 +0/-0.1 | ~2.3 |
| M6 | 1.0 | 5.00 | 11.00 | 12.12 | 8.00 | 0.75 ±0.15 | 0.50 +0/-0.1 | ~3.7 |
| M8 | 1.25 | 6.50 | 14.00 | 15.44 | 10.50 | 0.90 ±0.15 | 0.50 +0/-0.15 | ~7.3 |
| M10 | 1.5 | 8.00 | 17.00 | 18.72 | 12.50 | 1.15 ±0.2 | 0.65 +0/-0.15 | ~13.8 |
| M12 | 1.75 | 10.00 | 19.00 | 20.88 | 14.80 | 1.40 ±0.2 | 0.80 +0/-0.2 | ~21.9 |
| M14 | 2.0 | 10.00 | 19.00 | 20.88 | 14.80 | 1.40 ±0.2 | 1.00 +0/-0.2 | ~24.1 |
| M16 | 2.0 | 10.00 | 24.00 | 26.75 | 18.80 | 1.80 ±0.2 | 1.00 +0/-0.2 | ~37.0 |
* Across Corners (e) calculated from s × 1.155. Unit weights are theoretical reference values; actual weights may vary ±5%. M14 has limited availability — higher MOQ applies.
| Parameter | Specification |
|---|---|
| Standard | DIN 929 |
| Material | 10B21 Boron-Alloyed Medium-Strength Carbon Steel |
| Surface Treatment | Bare (Uncoated / Mill Finish) |
| ISO Property Class | Class 8 (per ISO 898-2) |
| Thread Type | Metric coarse thread (ISO 68-1) |
| Thread Tolerance | 6H |
| Nut Height Tolerance | h14 |
| Across Flats Tolerance | h13 |
| Spigot Diameter Tolerance | d11 |
| Welding Projections | 3 projections, symmetrically arranged |
| Welding Method | Resistance spot welding |
| Thread Size Range | M3 – M16 |
| Proof Load Stress | ≥ 800 MPa (Class 8) |
| Tensile Strength | ≥ 800 MPa (Class 8) |
| Hardness | 160–302 HV (Class 8) |
| Corrosion Resistance | Low (bare steel — post-process coating recommended for corrosive environments) |
| Typical Post-Process | E-coat, powder coat, paint, zinc plating (by customer) |
| RoHS Compliant | Yes |
| Packaging | Bulk bag / box; custom packaging available |
DIN 929 specifies hexagon weld nuts with three welding projections on the bearing face. The spigot (pilot) locates the nut precisely on the workpiece prior to welding. Upon resistance welding, the projections collapse and fuse with the base material, creating a flush, permanent joint. 10B21 is a boron-alloyed low-carbon steel (SAE 10B21 / GB 10B21 equivalent) widely used in the automotive and appliance industries for weld nuts and fasteners. At ISO Class 8, the material provides excellent weldability combined with reliable medium-high strength — the most common specification for general-purpose carbon steel weld nuts. The bare surface is the standard delivery condition for assemblies that will receive a subsequent coating process.
| Property | ISO Class 8 | ISO Class 10 |
|---|---|---|
| Proof Load Stress | ≥ 800 MPa | ≥ 900 MPa |
| Tensile Strength | ≥ 800 MPa | ≥ 1040 MPa |
| Hardness | 160–302 HV | 272–353 HV |
| Ductility | Higher | Lower |
| Weldability | Excellent | Good |
| Typical Use | General-purpose, appliance, light structural ✓ | High-load automotive BIW, heavy structural |
| Cost | Lower | Higher |
| Grade | Material | ISO Class | Tensile Strength | Corrosion Resistance | Typical Application |
|---|---|---|---|---|---|
| 10B21 Bare (Class 8) ✓ | Boron carbon steel | Class 8 | ≥ 800 MPa | Low (bare) | General-purpose, appliance, light structural, pre-coat |
| 10B21 Bare (Class 10) | Boron carbon steel | Class 10 | ≥ 1040 MPa | Low (bare) | Automotive BIW, heavy structural |
| A2 (SUS304) | Stainless steel | A2-70 | ≥ 700 MPa | Good | General industrial, indoor/outdoor |
| A4 (SUS316) | Marine stainless | A4-70 | ≥ 700 MPa | Excellent | Marine, chemical, food-grade |
DIN 929 Hex Weld Nuts — 10B21 Carbon Steel, ISO Class 8, Bare actual product photos:
| [ Photo 1 ] | [ Photo 2 ] | [ Photo 3 ] | [ Photo 4 ] |
| Grade | C (%) | Mn (%) | P (%) | S (%) | Si (%) | B (%) |
|---|---|---|---|---|---|---|
| 10B21 | 0.18–0.23 | 0.80–1.10 | ≤ 0.030 | ≤ 0.030 | 0.15–0.35 | 0.0005–0.003 |
* The boron (B) micro-addition improves hardenability while maintaining excellent weldability. Equivalent to SAE 10B21 / GB 10B21. Same base material as Class 10; property class difference is achieved through process control.
| Property Class | Proof Load Stress (MPa) | Tensile Strength (MPa) | Hardness (HV) | Min. Elongation |
|---|---|---|---|---|
| Class 8 | ≥ 800 | ≥ 800 | 160–302 | ≥ 12% |
* Class 8 offers higher ductility (min. 12% elongation vs 9% for Class 10) and superior weldability, making it the preferred grade for general-purpose and appliance weld nut applications.
7 Products
20% off all Cordless tool kits.
Fresh picks for your outdoor space, just in.