1. What is Screw Torque Tension Calculation?

The screw torque tension calculation determines the amount of torque required to achieve a specific clamping force in a bolted joint. This is essential for proper fastener installation and joint integrity in mechanical applications.

2. How Does the Calculator Work?

The calculator uses the screw torque tension formula:

Where:

• \( T \) — Torque (Newton-meters, Nm)
• \( K \) — Torque coefficient (dimensionless)
• \( F \) — Clamping force (Newtons, N)
• \( D \) — Nominal diameter (meters, m)

Explanation: The torque coefficient (K) accounts for friction and other factors that affect the relationship between applied torque and achieved tension.

3. Importance of Torque Calculation

Details: Proper torque calculation is crucial for ensuring joint integrity, preventing fastener failure, avoiding loosening under vibration, and achieving the desired clamping force in mechanical assemblies.

4. Using the Calculator

Tips: Enter the torque coefficient (typically 0.15-0.25 for standard fasteners), desired clamping force in Newtons, 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 unlubricated steel fasteners, K is typically between 0.15-0.25. Lubricated fasteners may have values as low as 0.10.

Q2: Why is proper torque important in fastening?
A: Proper torque ensures adequate clamping force without overstressing the fastener, which prevents joint failure, leakage, or loosening under vibration.

Q3: How does friction affect torque tension relationship?
A: Friction consumes a significant portion of applied torque (typically 85-90%), with only 10-15% actually creating clamp load. This is why the K factor is necessary.

Q4: When should I use a torque wrench?
A: Use a torque wrench for critical applications where consistent clamp load is essential, such as engine components, structural connections, or pressure-containing assemblies.

Q5: Are there limitations to this calculation?
A: This formula provides an estimate. Actual results may vary due to surface finish, lubrication, thread condition, and measurement accuracy. For critical applications, consult engineering specifications.