1. What Is The Screw Torque To Force Equation?

The Screw Torque To Force equation calculates the axial force generated from applied torque in threaded fasteners. It's particularly important for steel fasteners where proper clamping force is critical for joint integrity.

2. How Does The Calculator Work?

The calculator uses the screw torque to force formula:

Where:

• \( F \) — Axial force (lb)
• \( T \) — Applied torque (lb-in)
• \( K \) — Torque coefficient (dimensionless)
• \( D \) — Nominal diameter (in)

Explanation: The equation converts rotational torque into linear clamping force, accounting for friction and geometric factors through the torque coefficient.

3. Importance Of Force Calculation

Details: Accurate force calculation is essential for proper bolt tensioning, preventing joint failure, avoiding overtightening, and ensuring structural integrity in steel connections.

4. Using The Calculator

Tips: Enter torque in lb-in, torque coefficient as a decimal value, and diameter in inches. All values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical torque coefficient value for steel?
A: For steel fasteners, K typically ranges from 0.15 to 0.25, with 0.2 being a common default value for dry, unlubricated threads.

Q2: How does lubrication affect the torque coefficient?
A: Lubrication significantly reduces the torque coefficient, typically by 30-50%, allowing more clamping force for the same applied torque.

Q3: Why is diameter important in the calculation?
A: Larger diameters require more torque to achieve the same clamping force due to the increased lever arm effect.

Q4: Can this formula be used for metric units?
A: Yes, but units must be consistent (e.g., N·m for torque and mm for diameter will give force in Newtons when using appropriate coefficient).

Q5: What factors affect the torque coefficient?
A: Thread condition, lubrication, surface finish, material pairing, and thread fit all influence the torque coefficient value.