Bolt Bending Capacity Calculator

Bending Moment Formula:

\[ M = \frac{\pi \times d^3 \times S}{32} \]

Bending Moment Capacity (lb-in):

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1. What is a Bolt Bending Capacity Calculator?

Definition: This calculator determines the bending moment capacity of a bolt based on its diameter and material yield strength.

Purpose: It helps engineers and designers evaluate whether a bolt can withstand bending loads in structural applications.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ M = \frac{\pi \times d^3 \times S}{32} \]

Where:

\( M \) — Bending moment capacity (lb-in)
\( d \) — Bolt diameter (inches)
\( S \) — Material yield strength (psi)

Explanation: The formula calculates the elastic bending capacity based on the bolt's cross-sectional properties and material strength.

3. Importance of Bending Capacity Calculation

Details: Proper bolt bending evaluation ensures structural integrity, prevents fastener failure, and maintains safety in mechanical connections.

4. Using the Calculator

Tips: Enter the bolt diameter in inches and material yield strength in psi (default 36000 psi for Grade 2 bolts). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical yield strength for bolts?
A: Common values: Grade 2 (36,000 psi), Grade 5 (92,000 psi), Grade 8 (130,000 psi).

Q2: Does this account for shear loads?
A: No, this calculates pure bending capacity only. Combined loading requires additional analysis.

Q3: Is this formula valid for all bolt materials?
A: Yes, as long as you use the correct yield strength (S) for the specific material.

Q4: How does thread affect bending capacity?
A: This calculates full-diameter capacity. Threaded portions have reduced capacity - use root diameter for precise calculations.

Q5: What safety factor should I apply?
A: Typical safety factors range from 1.5 to 3.0 depending on application criticality.