Gas Piping Size Calculator

Calculate Gas Flow Rate







Formula

The formula to calculate the flow rate of natural gas through a pipe is:

\[ q = 3550 \left[ \frac{d^5}{1 + \frac{3.6}{d} + 0.03d} \right]^{1/2} \left( \frac{h}{L \cdot SG} \right)^{1/2} \]

Where:

What is a Gas Pipe Size?

The correct gas pipe size depends on the diameter, length, and pressure drop of the pipe. It also depends on the specific gravity of the gas moving through the pipe.

Example Calculations

Example 1:

Using the formula:

\[ q = 3550 \left[ \frac{2^5}{1 + \frac{3.6}{2} + 0.03 \cdot 2} \right]^{1/2} \left( \frac{10}{50 \cdot 0.60} \right)^{1/2} \]

Calculating step-by-step:

\[ q = 3550 \left[ \frac{32}{1 + 1.8 + 0.06} \right]^{1/2} \left( \frac{10}{30} \right)^{1/2} \]

\[ q = 3550 \left[ \frac{32}{2.86} \right]^{1/2} \left( \frac{1}{3} \right)^{1/2} \]

\[ q = 3550 \left[ 11.19 \right]^{1/2} \left( 0.333 \right)^{1/2} \]

\[ q = 3550 \cdot 3.34 \cdot 0.577 \]

\[ q \approx 6855.8 \text{ cfh} \]

Example 2:

Using the formula:

\[ q = 3550 \left[ \frac{3^5}{1 + \frac{3.6}{3} + 0.03 \cdot 3} \right]^{1/2} \left( \frac{15}{100 \cdot 0.60} \right)^{1/2} \]

Calculating step-by-step:

\[ q = 3550 \left[ \frac{243}{1 + 1.2 + 0.09} \right]^{1/2} \left( \frac{15}{60} \right)^{1/2} \]

\[ q = 3550 \left[ \frac{243}{2.29} \right]^{1/2} \left( \frac{1}{4} \right)^{1/2} \]

\[ q = 3550 \left[ 106.11 \right]^{1/2} \left( 0.25 \right)^{1/2} \]

\[ q = 3550 \cdot 10.30 \cdot 0.5 \]

\[ q \approx 18282.75 \text{ cfh} \]