Purge Time Calculator

Formula

The formula to calculate the purge time is:

\[ \text{PT} = \frac{\pi \times D}{12} \times \frac{L}{PR} \times 60 \]

Where:

\( \text{PT} \) is the purge time (minutes).
\( D \) is the pipe diameter (inches).
\( L \) is the pipe length (feet).
\( PR \) is the purge rate (cfh, cubic feet per hour).

What is Purge Time?

Purge time refers to the time required to completely replace the air or any other gas inside a pipe with an inert gas or a new type of gas. This is important in various industrial processes to prevent contamination, oxidation, or explosions.

Example Calculation

Let's consider an example:

Pipe Diameter (D): 10 inches
Pipe Length (L): 100 feet
Purge Rate (PR): 200 cfh

Using the formula to calculate the purge time:

\[ \text{PT} = \frac{\pi \times 10}{12} \times \frac{100}{200} \times 60 \approx 78.54 \text{ minutes} \]

This means that the purge time for this scenario is approximately 78.54 minutes.