Bolt Torque Calculator

Author: Neo Huang Review By: Nancy Deng
LAST UPDATED: 2024-07-21 20:32:30 TOTAL USAGE: 215 TAG:

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The Bolt Torque Calculator is a free tool that helps determine the correct rotational force needed to tighten a bolt. Torque is a measure of the rotational force applied at a certain distance from the rotation axis. When selecting the clamping force option in the input panel, the following tool can also serve as a clamping force calculator.

How to Calculate Bolt Torque

To start using this bolt torque calculator, you will need some details on hand. The first factor is the K constant, which accounts for the friction characteristics of the bolt and mating parts. The bolt diameter is also required. Additionally, a lubrication coefficient can be included in the calculation. Finally, the torque or clamping force to be applied to the bolt needs to be provided before running the bolt calculation.

Bolt Torque Calculation Formula

The formula used in this calculator is:

\[ \text{Required Torque (T)} = k \cdot d \cdot F \cdot (1 + C_l) \]


  • \( k \) is the nut factor constant depending on the bolt size and material.
  • \( d \) is the bolt diameter (in mm).
  • \( C_l \) is the lubrication coefficient.
  • \( F \) is the clamping force (in N·m).

Importance of Bolt Torque

Bolt torque is crucial for ensuring that the correct clamping torque is applied to bolted connections. By using a bolt torque calculator, engineers can ensure the integrity, performance, and tightness of bolted joints across multiple connections.

Common FAQs

  1. Why is bolt torque important?

    • Bolt torque ensures the correct clamping force is applied, maintaining the integrity and performance of the connection.
  2. What factors affect bolt torque?

    • Factors include bolt diameter, bolt threads, material properties, and lubrication. These can be easily determined using the calculator.
  3. Where can I find torque specifications?

    • Torque specifications can be found from bolt manufacturers and engineering standards.