键槽应力计算器 — 公式
## Parallel Key Stress Analysis
A key transmits torque between a shaft and a hub (gear, pulley, coupling).
### Formulas
The tangential force at the shaft surface: **F = 2T / d**
**Shear stress = F / (w x L)** (shear across the key width)
**Bearing stress = F / ((h/2) x L)** (crushing on half the key height)
where T is torque, d is shaft diameter, w is key width, h is key height, and L is key engagement length. Bearing stress is usually the governing criterion.
A key transmits torque between a shaft and a hub (gear, pulley, coupling).
### Formulas
The tangential force at the shaft surface: **F = 2T / d**
**Shear stress = F / (w x L)** (shear across the key width)
**Bearing stress = F / ((h/2) x L)** (crushing on half the key height)
where T is torque, d is shaft diameter, w is key width, h is key height, and L is key engagement length. Bearing stress is usually the governing criterion.
计算示例
A 12x8 mm key, 40 mm long, on a 40 mm shaft transmitting 200 N-m.
- F = 2 x 200,000 / 40 = 10,000 N
- Shear stress = 10,000 / (12 x 40) = 20.8 MPa
- Bearing stress = 10,000 / (4 x 40) = 62.5 MPa
- Bearing stress governs. For mild steel key (allowable bearing ~90 MPa), the key is adequate.