1. What is the Bolt Clamping Force Formula?

The bolt clamping force formula calculates the axial force generated when torque is applied to a bolt. This force is crucial for maintaining joint integrity and preventing loosening in mechanical assemblies.

2. How Does the Calculator Work?

The calculator uses the bolt clamping force formula:

Where:

• \( F \) — Clamping force (N)
• \( T \) — Applied torque (Nm)
• \( K \) — Torque coefficient (dimensionless)
• \( D \) — Bolt diameter (m)

Explanation: The formula relates applied torque to the resulting clamping force, accounting for friction and geometric factors through the torque coefficient.

3. Importance of Clamping Force Calculation

Details: Accurate clamping force calculation is essential for proper bolt tightening, preventing joint failure, ensuring structural integrity, and avoiding damage to fastened components.

4. Using the Calculator

Tips: Enter torque in Nm, torque coefficient (typically 0.15-0.25 for standard bolts), and bolt diameter in meters. All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical torque coefficient value?
A: For standard steel bolts, K is typically between 0.15-0.25, but varies with lubrication, surface finish, and thread condition.

Q2: Why is clamping force important?
A: Proper clamping force ensures joint integrity, prevents loosening from vibration, and maintains seal pressure in gasketed joints.

Q3: How accurate is this formula?
A: The formula provides a good estimate but actual values may vary due to friction variations, thread quality, and lubrication conditions.

Q4: What affects the torque coefficient?
A: Surface finish, lubrication, thread pitch, material combination, and washers all influence the torque coefficient value.

Q5: Can this formula be used for all bolt types?
A: While the basic formula applies to most bolts, specialized fasteners may require modified calculations or specific torque tables.