F = force (kN)
Preliminary press-brake air-bend force
Preliminary metric air-bending estimate with explicitly entered tensile strength, thickness, bend length and V-opening.
FORMULA REFERENCE
F = 1.42Rm t²L/(V × 1000)
Preliminary metric air-bending estimate with explicitly entered tensile strength, thickness, bend length and V-opening.
Variables and units
Keep each value in the units shown below before substituting it into the displayed relation. Convert first rather than mixing unit systems inside one calculation.
Rm = tensile strength (MPa)
t = thickness (mm)
L = bend length (mm)
V = V-opening (mm)
WORKED EXAMPLE
Calculate the stated condition, then interpret its boundary.
Known values
- Rm = 450 MPa
- t = 2 mm
- L = 1,000 mm
- V = 16 mm
Substitution: F = 1.42 × 450 × 2² × 1,000 / (16 × 1,000)
Calculated result: F = 159.8 kN ≈ 16.3 tonne-force
Engineering interpretation: Apply suitable tooling, machine and safety margins; verify capacity with the press-brake manufacturer chart.
Conditions, limitations and review
- Air bending baseline only
- Straight uniformly loaded bend
- Tooling/machine charts control final selection
Use this formula to understand or screen the stated engineering condition. A final design requires the governing standard, actual loads, material condition, manufacturing features and professional engineering judgement.
Source: Manufacturer press-brake engineering charts; the calculator labels this as a preliminary air-bend estimate.