Fastener Torque Calculator

Formula

To calculate the Fastener Torque (\(Tf\)):

\[ Tf = \frac{D \times P \times K}{12} \]

Where:

\(Tf\) is the Fastener Torque (lbf-ft)
\(D\) is the Nominal Diameter (in)
\(P\) is the Desired Clamp Load (lbf)
\(K\) is the Coefficient of Friction

What is Fastener Torque?

Fastener torque is the amount of rotational force applied to a fastener, such as a bolt or screw, to achieve the desired clamp load. It is a critical parameter in ensuring the proper assembly and performance of mechanical systems.

Example Calculation 1

Let's assume the following values:

Nominal Diameter (\(D\)) = 0.5 in
Desired Clamp Load (\(P\)) = 1000 lbf
Coefficient of Friction (\(K\)) = 0.2

Using the formula:

\[ Tf = \frac{0.5 \times 1000 \times 0.2}{12} = 8.33 \text{ lbf-ft} \]

The Fastener Torque is 8.33 lbf-ft.

Example Calculation 2

Let's assume the following values:

Nominal Diameter (\(D\)) = 1 in
Desired Clamp Load (\(P\)) = 2000 lbf
Coefficient of Friction (\(K\)) = 0.15

Using the formula:

\[ Tf = \frac{1 \times 2000 \times 0.15}{12} = 25 \text{ lbf-ft} \]

The Fastener Torque is 25 lbf-ft.