Shear Strength of Key Calculator

Tangential Force Formula:

\[ F = l \times b_k \times f_s \]

Length of Key:

Width of Key:

Shear Stress in Key:

Tolerance:

Tangential Force (N):

1. What is Shear Strength of Key Calculator?

Definition: This calculator determines the tangential force a key can withstand before shearing, based on its dimensions and material properties.

Purpose: It helps mechanical engineers and designers ensure keys in shaft assemblies can handle expected loads without failure.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ F = l \times b_k \times f_s \]

Where:

\( F \) — Tangential force (Newtons)
\( l \) — Length of key (meters)
\( b_k \) — Width of key (meters)
\( f_s \) — Shear stress in key (Pascals)

Explanation: The force is calculated by multiplying the key's shear area (length × width) by the material's shear stress capacity.

3. Importance of Key Shear Strength Calculation

Details: Proper calculation ensures mechanical connections can transmit torque without key failure, preventing equipment damage and safety hazards.

4. Using the Calculator

Tips: Enter key dimensions in meters, shear stress in Pascals, and optional tolerance percentage. All dimensional values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical shear stress value for keys?
A: Common steel keys have shear stress values between 50-100 MPa, but always consult material specifications.

Q2: Why include a tolerance percentage?
A: Tolerance accounts for material variations, manufacturing imperfections, and safety factors.

Q3: Should I use maximum or minimum dimensions for safety?
A: For conservative estimates, use minimum dimensions and maximum stress values.

Q4: How does key shape affect the calculation?
A: This formula assumes rectangular keys. Other shapes (Woodruff, round) require different formulas.

Q5: What safety factor should I apply?
A: Typical safety factors range from 2-5 depending on application criticality and load certainty.