Screw Torque Tension Calculator

Screw Torque Tension Formula:

\[ F = \frac{Torque}{K \times d} \]

F (Newtons):

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1. What is the Screw Torque Tension Formula?

The Screw Torque Tension Formula calculates the axial force (tension) generated in a screw or bolt when a specific torque is applied. This relationship is fundamental in mechanical engineering and fastener design.

2. How Does the Calculator Work?

The calculator uses the screw torque tension formula:

\[ F = \frac{Torque}{K \times d} \]

Where:

\( F \) — Axial tension force (Newtons)
\( Torque \) — Applied torque (Newton-meters)
\( K \) — Dimensionless torque coefficient
\( d \) — Nominal diameter of the screw (meters)

Explanation: The formula relates applied torque to the resulting axial tension in a screw, accounting for friction and geometric factors through the torque coefficient K.

3. Importance of Screw Tension Calculation

Details: Accurate screw tension calculation is crucial for proper fastener installation, ensuring adequate clamping force while preventing over-torquing that could lead to bolt failure or thread damage.

4. Using the Calculator

Tips: Enter torque in Nm, K value (typically 0.15-0.25 for standard fasteners), and screw diameter in meters. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical range for K values?
A: K values typically range from 0.15 to 0.25 for standard fasteners, but can vary based on lubrication, surface finish, and thread type.

Q2: Why is screw tension important?
A: Proper screw tension ensures joint integrity, prevents loosening under vibration, and maintains sealing pressure in gasketed joints.

Q3: How accurate is this formula?
A: The formula provides a good estimate but actual tension can vary ±25% due to friction variations. Critical applications may require direct tension measurement.

Q4: What affects the K value?
A: K value is influenced by thread friction, bearing surface friction, lubrication, surface finish, and material properties.

Q5: Can this formula be used for all fastener types?
A: The formula works for standard threaded fasteners. Special fasteners like torque-to-yield or prevailing torque nuts may require different calculations.