1. What is the Diameter of Shaft with Keyway?

The diameter of shaft with keyway is defined as the external surface diameter of a shaft (a rotating machine element) with a keyway. It represents the modified shaft diameter that accounts for the presence of a keyway, which affects the shaft's torsional strength.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( d \) — Diameter of shaft with keyway (m)
• \( b_k \) — Width of key in round shaft (m)
• \( h \) — Height of shaft keyway (m)
• \( C \) — Ratio of shaft strength with and without keyway

Explanation: This formula calculates the required shaft diameter that accounts for the reduction in torsional strength caused by the presence of a keyway, ensuring the shaft maintains adequate strength for its intended application.

3. Importance of Shaft Diameter Calculation

Details: Accurate calculation of shaft diameter with keyway is crucial for mechanical design and engineering. It ensures that the shaft can transmit the required torque while maintaining structural integrity, preventing failure due to torsional stresses, and accounting for the strength reduction caused by the keyway.

4. Using the Calculator

Tips: Enter the width of key in meters, height of shaft keyway in meters, and the ratio of shaft strength (0 ≤ C < 1). All values must be positive numbers with the strength ratio between 0 and 1 (exclusive of 1).

5. Frequently Asked Questions (FAQ)

Q1: What is a keyway in shaft design?
A: A keyway is a longitudinal slot machined into a shaft that accommodates a key, which prevents relative rotation between the shaft and mounted components like gears or pulleys.

Q2: Why does a keyway reduce shaft strength?
A: The keyway creates a stress concentration point and reduces the cross-sectional area of the shaft, both of which decrease the shaft's torsional strength capacity.

Q3: What is the typical range for the strength ratio C?
A: The ratio C typically ranges from 0.75 to 0.95, meaning the keyway reduces shaft strength by 5% to 25% compared to a solid shaft without a keyway.

Q4: How is the strength ratio C determined?
A: The strength ratio is determined through experimental testing or finite element analysis, comparing the torsional strength of identical shafts with and without keyways.

Q5: Are there different formulas for different keyway shapes?
A: Yes, different keyway profiles (rectangular, semicircular, etc.) may require modified formulas to account for their specific stress concentration factors and strength reduction characteristics.