1. What is the Length of Key Formula?

The Length of Key formula calculates the required length of a key to prevent rotation of machine components based on tangential force, crushing stress, and key thickness. It ensures proper mechanical design and prevents key failure.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( l \) — Length of Key (mm)
• \( F \) — Tangential Force (N)
• \( f_c \) — Crushing Stress in Key (Pa)
• \( t \) — Thickness of Key (mm)

Explanation: The formula calculates the minimum key length required to withstand the crushing stress caused by the tangential force transmitted through the key.

3. Importance of Key Length Calculation

Details: Proper key length calculation is essential for mechanical design to ensure power transmission efficiency, prevent key failure, and maintain the integrity of shaft-hub connections in machinery.

4. Using the Calculator

Tips: Enter tangential force in Newtons, crushing stress in Pascals, and key thickness in millimeters. All values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is tangential force in key design?
A: Tangential force is the force that acts tangentially to the shaft surface, transmitted through the key from the hub to the shaft or vice versa.

Q2: Why is crushing stress important in key design?
A: Crushing stress determines the key's ability to withstand compressive forces without deformation or failure, ensuring reliable power transmission.

Q3: How is key thickness typically determined?
A: Key thickness is usually taken as one-sixth of the shaft diameter, following standard mechanical design practices.

Q4: What factors affect key length requirements?
A: Higher tangential forces, lower crushing stress materials, and thinner keys require longer key lengths to prevent failure.

Q5: Are there standard key dimensions?
A: Yes, most countries have standardized key dimensions (e.g., ANSI, ISO standards) based on shaft diameters to ensure compatibility and safety.