キー溝深さ計算

Keyway and key dimension formulas

Keyways transmit torque between shafts and hubs via a square or rectangular key. The keyway dimensions are standardised based on shaft diameter. This calculator provides approximate key and keyway sizes for common shaft diameters.

• Key width ≈ shaft diameter × 0.25 (for shafts under 25 mm)
• Key height ≈ shaft diameter × 0.15 (for shafts under 25 mm)
• Keyway depth in shaft ≈ shaft diameter × 0.15
• For shafts over 25 mm: key width ≈ 0.2×D, key height ≈ 0.12×D

How to use this Keyway Depth & Key Dimensions Calculator

Enter the shaft diameter. The calculator suggests standard key width, key height, and keyway depth based on common ISO/ANSI proportions. Always verify against your specific standard (DIN 6885, ANSI B17.1, JIS B1301) for critical applications.