Shaft Key Shear Calculator
Shear and crushing checks on a parallel key.
Crushing usually governs — only half the key height bears on each side. The key is the designed fuse: cheaper to shear a ₹50 key than a gearbox. Keep τ under ~60 MPa for C45 keys.
Formula
Shaft Key Shear Calculator is a free key shear for mechanical and machine-design engineers — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Shaft Key Shear Calculator
Shear and crushing checks on a parallel key. The calculation implements F = 2T/d; τ = F/(w·L); σ_c = F/(h/2·L) (DIN 6885; Shigley keys & couplings). Crushing usually governs — only half the key height bears on each side. The key is the designed fuse: cheaper to shear a ₹50 key than a gearbox. Keep τ under ~60 MPa for C45 keys.
How to use Shaft Key Shear Calculator
- 1Enter Torque in N·m.
- 2Enter Shaft diameter in mm.
- 3Enter Key width in mm (DIN 6885: Ø40 → 12×8 key).
- 4Enter Key height in mm.
- 5Read Key shear stress, Crushing (side) stress instantly — no submit button needed.
- 6Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Shaft Key Shear Calculator?
- ✓Implements the standard formula — F = 2T/d; τ = F/(w·L); σ_c = F/(h/2·L)
- ✓Reference cited on-page: DIN 6885; Shigley keys & couplings
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Shaft Key Shear Calculator use?+
It computes F = 2T/d; τ = F/(w·L); σ_c = F/(h/2·L), per DIN 6885; Shigley keys & couplings. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
Crushing usually governs — only half the key height bears on each side. The key is the designed fuse: cheaper to shear a ₹50 key than a gearbox. Keep τ under ~60 MPa for C45 keys.
Is this suitable for machine design coursework?+
Yes — these are the exact Shigley/Machinery's-Handbook formulas, with the substitution shown step by step, so you can follow the worked example into your own calculation sheet.
Is the Shaft Key Shear Calculator free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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