| Shaft & Key | ||
| Shaft Diam. D | ||
|---|---|---|
| Key Standard | ||
| Key Size | ||
| Key Width w | ||
| Key Height h | ||
| Shaft Seat Depth t1 Keyseat depth in the shaft, measured from the shaft's outer diameter. ANSI keys use h/2; DIN values are from DIN 6885. | ||
| Hub Seat Depth t2 Keyway depth in the hub, measured from the shaft's outer diameter. | ||
| Key Length L | ||
| Key Ends | ||
| Number of Keys Two keys at 180° share load unevenly due to fit tolerances. Following DIN 6892, they're taken to carry 1.5× one key, not 2×. | ||
| Keyseat Type | ||
| Keyseat Fillet r Radius at the bottom corners of the shaft keyseat. Blank = 0.02·D (a typical value; Shigley). | ||
| Loads | ||
| Torque, Mean Tm | ||
|---|---|---|
| Torque, Alternating Ta Amplitude of torque fluctuation. Peak torque Tm + Ta is used for the static key checks. | ||
| Bending, Alternating Ma Bending moment at the keyseat. On a rotating shaft, a steady bending load is fully reversed, so enter it here. | ||
| Bending, Mean Mm | ||
| Target FOS | ||
| Materials | ||
| Key Material | ||
|---|---|---|
| Key Grade | ||
| Key Sy | ||
| Shaft Material | ||
| Shaft Grade | ||
| Shaft Sy | ||
| Shaft Su | ||
| Shaft Se' Uncorrected endurance limit. Blank = no fatigue check. | ||
| Marin Factor k Product ka·kb·kc·kd·ke of the endurance-limit modifiers (surface, size, load, temperature, reliability). Machined steel shafts are typically 0.6–0.8. | ||
| Notch Sens. q / qs Bending / torsion notch sensitivity. Blank = computed from the Neuber constant for steels (Shigley eq. 6-35); 1 for other materials. | ||
| Hub Material | ||
| Hub Grade | ||
| Hub Sy | ||
| Key | ||
| Force at Shaft Surface F | ||
|---|---|---|
| Force per Key | ||
| Effective Length Leff | ||
| Key Shear Stress τ | ||
| FOS, Key Shear | ||
| Bearing, Shaft Side | ||
| FOS, Bearing Shaft Side | ||
| Bearing, Hub Side | ||
| FOS, Bearing Hub Side | ||
| Min. Key Length for Target FOS Shortest key whose shear and bearing checks all meet the target FOS. Doesn't include the shaft checks, which don't depend on key length. | ||
| Shaft at Keyseat | ||
| Fillet Radius Used r | ||
| Kt / Kts | ||
| q / qs | ||
| Kf / Kfs | ||
| von Mises σ'a | ||
| von Mises σ'm | ||
| FOS, Fatigue (Goodman) | ||
| FOS, First-Cycle Yield Sy / (σ'a + σ'm), using Kf (Shigley eq. 7-16). | ||
| Overall | ||
| Minimum FOS | ||
| Governed By | ||