1. What is Screw Clamp Strength?

Screw clamp strength refers to the axial force generated by a screw fastener when a specific torque is applied. It's crucial for ensuring proper joint integrity in mechanical assemblies.

2. How Does the Calculator Work?

The calculator uses the screw clamp strength formula:

Where:

• \( Torque \) — Applied torque (Nm)
• \( K \) — Torque coefficient (unitless)
• \( D \) — Nominal diameter (m)

Explanation: The equation shows that clamp strength is directly proportional to applied torque and inversely proportional to both the torque coefficient and bolt diameter.

3. Importance of Clamp Strength Calculation

Details: Proper clamp force ensures joint integrity, prevents loosening, and maintains seal pressure in bolted connections. Under-torquing can lead to joint failure while over-torquing may damage components.

4. Using the Calculator

Tips: Enter torque in Nm, K factor (typically 0.2 for dry steel), and diameter in meters. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical range for K factor?
A: K typically ranges from 0.1 to 0.3, with 0.2 being common for dry steel connections. Lubricated threads may have lower K values.

Q2: How does thread pitch affect clamp strength?
A: Finer threads generally provide greater clamp strength for the same torque due to better mechanical advantage.

Q3: What affects torque coefficient (K)?
A: Surface finish, lubrication, thread condition, and material combinations all influence the K factor.

Q4: Why is bolt diameter important?
A: Larger diameter bolts require more torque to achieve the same clamp force due to increased friction radius.

Q5: How accurate is this calculation?
A: This provides an estimate. Actual clamp force can vary ±25% due to friction variations and other factors.