Diameter of bolt given torque resisted by one bolt Calculator

Diameter of Bolt Formula:

\[ d_{bolt} = \sqrt{\frac{8 \times T_{bolt}}{f_s \times \pi \times d_{pitch}}} \]

Diameter of Bolt (m):

1. What is Diameter of Bolt Calculator?

Definition: This calculator determines the required diameter of a bolt based on the torque it needs to resist, shear stress, and bolt pitch circle diameter.

Purpose: It helps mechanical engineers and designers properly size bolts for various applications where torque resistance is critical.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ d_{bolt} = \sqrt{\frac{8 \times T_{bolt}}{f_s \times \pi \times d_{pitch}}} \]

Where:

\( d_{bolt} \) — Diameter of bolt (meters)
\( T_{bolt} \) — Torque resisted by bolt (N·m)
\( f_s \) — Shear stress in bolt (Pascals)
\( d_{pitch} \) — Diameter of bolt pitch circle (meters)

Explanation: The formula calculates the minimum bolt diameter needed to resist a given torque while staying within allowable shear stress limits.

3. Importance of Bolt Diameter Calculation

Details: Proper bolt sizing ensures structural integrity, prevents mechanical failure, and maintains safety in assemblies under torque loads.

4. Using the Calculator

Tips: Enter the torque value, allowable shear stress, and pitch circle diameter. All values must be > 0. Results include a ±5% tolerance.

5. Frequently Asked Questions (FAQ)

Q1: Why is there a ±5% tolerance?
A: The tolerance accounts for material variations, manufacturing tolerances, and safety factors in real-world applications.

Q2: What's a typical shear stress value for bolts?
A: Common values range from 140-350 MPa for steel bolts, but always consult material specifications.

Q3: How do I determine the pitch circle diameter?
A: It's the diameter of the circle that passes through the center of all bolts in a pattern.

Q4: Does this account for multiple bolts?
A: No, this calculates for a single bolt. For multiple bolts, divide the total torque by the number of bolts.

Q5: What if my bolt material has different properties?
A: Adjust the shear stress value accordingly based on your material's specifications.