Frame Stiffness
Frame corner moments, horizontal / vertical deformation and L/H accuracy check.
🧱 Input Parameters
kN
cm
cm
cm⁴
cm⁴
cm⁴
MPa
n
📌 Note
Closed-frame simplified stiffness model (symmetric 2-column frame, central load P). MA = MB = P·L/4·ρ/(2+ρ), ρ=(I3·L)/(I_b·H) with I_b=(I1+I2)/2. Δh = MA·H²/(6·EI3); ΔV = P·L³/(48·E·I_b).
Accuracy: allowable ΔV ≤ L / n (n = accuracy factor). For precision presses n≈3000~5000; excess ΔV indicates insufficient stiffness, Δh guides guidance check.
Tilt Δh/H ≤ 1‰ keeps columns square; allowable horizontal ΔhA ≤ H/1000 (column guide clearance budget).
🗺️ Schematic
Closed frame