1. What is Screw Clamping Force?

Screw clamping force refers to the compressive force generated when a screw or bolt is tightened. It is a critical parameter in mechanical design and assembly, ensuring proper joint integrity and preventing loosening under operational loads.

2. How Does the Calculator Work?

The calculator uses the screw clamping force formula:

Where:

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

Explanation: The formula calculates the axial clamping force generated by a screw based on the applied torque, screw diameter, and a friction-dependent coefficient.

3. Importance of Clamping Force Calculation

Details: Accurate clamping force calculation is essential for ensuring proper joint preload, preventing bolt fatigue failure, maintaining seal integrity, and avoiding joint slippage in mechanical assemblies.

4. Using the Calculator

Tips: Enter torque in Nm, coefficient value (typically 0.2 for standard conditions), and screw diameter in meters. All values must be positive and valid.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical range for torque coefficient K?
A: The torque coefficient typically ranges from 0.15 to 0.25 for most applications, with 0.2 being a common standard value.

Q2: How does lubrication affect the calculation?
A: Lubrication reduces friction and therefore the K value, resulting in higher clamping force for the same applied torque.

Q3: Why is proper clamping force important?
A: Insufficient force can lead to joint loosening, while excessive force may cause bolt yielding or thread stripping.

Q4: What factors influence the torque coefficient?
A: Surface finish, lubrication, thread pitch, material properties, and installation speed all affect the K value.

Q5: Should torque be measured during assembly?
A: Yes, torque measurement is critical for quality control and ensuring consistent clamping force across multiple fasteners.