Bending force in tonnes per metre, calculated for 90° air bending of mild steel (tensile strength σb = 420 MPa) over a 1 m length. Read down your material thickness (t), across to the V-die opening (V).
| t (mm) ↓ / V → | V6 | V8 | V10 | V12 | V16 | V20 | V32 | V50 | V80 | V100 |
|---|---|---|---|---|---|---|---|---|---|---|
| 0.8 | 7 | 4.8 | — | — | — | — | — | — | — | — |
| 1.0 | 11 | 8 | 6 | — | — | — | — | — | — | — |
| 1.5 | — | 15 | 12 | 8 | — | — | — | — | — | — |
| 2.0 | — | 23 | 16 | 13 | 9.5 | — | — | — | — | — |
| 3.0 | — | — | 30 | 24 | 16 | 12 | — | — | — | — |
| 4.0 | — | — | — | 44 | 28 | 18 | — | — | — | — |
| 5.0 | — | — | — | — | 43 | 25 | — | — | — | — |
| 6.0 | — | — | — | — | — | 36 | — | — | — | — |
| 8.0 | — | — | — | — | — | 65 | 36 | — | — | — |
| 10 | — | — | — | — | — | — | 60 | 43 | — | — |
| 12 | — | — | — | — | — | — | 90 | 58 | 50 | — |
| 16 | — | — | — | — | — | — | — | 115 | 81 | 71 |
| 20 | — | — | — | — | — | — | — | — | 130 | 90 |
Approximate tonnage F (Ton/m) = 65 × t² / V. Values above are indicative — request the full chart (V6–V260, t 0.5–20 mm) as a PDF.
Recommended V-die opening by material thickness. Inside radius ≈ 16% of the V-opening.
| Material thickness (t) | Recommended V-opening |
|---|---|
| 0.5 – 2.5 mm | V = 6 × t |
| 3 – 8 mm | V = 8 × t |
| 9 – 10 mm | V = 10 × t |
| > 12 mm | V = 12 × t |
The capacity chart is for mild steel. For other materials, multiply the chart value:
| Material | Tensile strength | Force factor |
|---|---|---|
| Aluminium | σb ≈ 300 MPa | × 0.65 |
| Mild steel | σb ≈ 420 MPa | × 1.0 (chart) |
| Stainless steel | σb ≈ 700 MPa | × 1.6 |
Send your material, thickness, bend angle and machine — our engineers will specify the tooling.
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