1. What is Screw Clamp Force?

Screw clamp force refers to the axial force generated when torque is applied to a screw or bolt. This force is crucial in various mechanical applications where components need to be securely fastened together.

2. How Does the Calculator Work?

The calculator uses the screw clamp force formula:

Where:

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

Explanation: The formula calculates the axial force generated by a screw or bolt based on the applied torque, accounting for friction and geometric factors through the torque coefficient.

3. Importance of Clamp Force Calculation

Details: Accurate clamp force calculation is essential for ensuring proper joint integrity, preventing loosening under vibration, avoiding damage to clamped components, and maintaining safety in mechanical assemblies.

4. Using the Calculator

Tips: Enter torque in Nm, torque coefficient (typically between 0.1-0.3 for most applications), and nominal diameter in meters. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical value for the torque coefficient K?
A: For standard bolts with lubrication, K is typically between 0.15-0.2. Without lubrication, it can range from 0.2-0.3.

Q2: Why is clamp force important in bolted joints?
A: Proper clamp force ensures the joint remains tight under operating conditions, prevents leakage in sealed joints, and maintains structural integrity.

Q3: How does thread friction affect clamp force?
A: Higher thread friction reduces the clamp force generated for a given torque, as more torque is consumed overcoming friction rather than generating tension.

Q4: What factors influence the torque coefficient K?
A: Surface finish, lubrication, thread type, material combination, and plating/coating all affect the torque coefficient value.

Q5: Can this formula be used for all types of screws and bolts?
A: While the basic principle applies to most threaded fasteners, specific applications may require more complex calculations that account for additional factors like thread pitch and head friction.