1. What is Thread Clamping Force?

Thread clamping force refers to the axial force generated when a threaded fastener (such as a bolt or screw) is tightened. This force is crucial for maintaining joint integrity and preventing loosening under various loads and vibrations.

2. How Does the Calculator Work?

The calculator uses the thread clamping force formula:

Where:

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

Explanation: The formula calculates the axial force generated in a bolted joint based on the applied torque, fastener diameter, and a coefficient that accounts for friction and thread geometry.

3. Importance of Clamping Force Calculation

Details: Proper clamping force is essential for joint integrity, preventing bolt fatigue failure, maintaining seal pressure, and ensuring structural stability in mechanical assemblies.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: What is a typical value for coefficient K?
A: For standard unlubricated steel bolts, K is typically around 0.2. Lubricated bolts may have K values around 0.15-0.18.

Q2: Why is clamping force important?
A: Proper clamping force ensures joint integrity, prevents loosening from vibration, maintains seal pressure, and prevents bolt fatigue failure.

Q3: How accurate is this calculation?
A: This provides an estimate. Actual force can vary due to surface conditions, lubrication, thread quality, and measurement accuracy.

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

Q5: When should I use torque measurement vs. tension measurement?
A: Torque measurement is more common and practical for field applications, while direct tension measurement is more accurate for critical applications.