How to Calculate Pipe Size From Flow Rate

1. Divide the volumetric flow rate by the linear flow rate. This will give the area of a cross section of the pipe.

2. Divide the area of the pipe by 3.14159.

3. Take the square root of the result from Step 2. This gives the internal radius of the pipe.

4. Multiply the internal radius of the pipe by 2. This is the internal diameter of the pipe. This value indicates the pipe size based on the linear and volumetric flow rate.