1. What is Axial Bolt Force?

Axial bolt force is the tension force generated in a bolt when torque is applied during tightening. It's crucial for ensuring proper joint clamping force in bolted connections.

2. How Does the Calculator Work?

The calculator uses the axial bolt force formula:

Where:

• \( F \) — Axial bolt force (N)
• \( T \) — Applied torque (Nm)
• \( d \) — Bolt diameter (m)
• 0.2 — Empirical coefficient (friction factor)

Explanation: The formula estimates the axial force based on torque input, accounting for typical friction conditions in bolted joints.

3. Importance of Axial Bolt Force Calculation

Details: Proper bolt tension is essential for joint integrity. Too little force can lead to loosening, while excessive force may cause bolt failure.

4. Using the Calculator

Tips: Enter torque in Nm and bolt diameter in meters. Both values must be positive numbers for valid calculation.

5. Frequently Asked Questions (FAQ)

Q1: Why is the coefficient 0.2 used?
A: This empirical factor accounts for typical friction conditions between threads and under the bolt head/nut.

Q2: How accurate is this calculation?
A: It provides a good estimate but actual force can vary ±25% due to friction variations in real applications.

Q3: What affects bolt tension accuracy?
A: Surface finish, lubrication, thread condition, and tightening speed all influence the torque-tension relationship.

Q4: When should I use more precise methods?
A: For critical applications, consider direct tension measurement or ultrasonic bolt elongation measurement.

Q5: Does this work for all bolt types?
A: The formula applies generally, but specific coefficients may vary for different thread standards or materials.