What is the recommended size of tubing to install for a gas line that is 520 feet long with a pressure drop of 0.3 in. w.c.?

The correct choice of 1-1/2 inch tubing for a gas line that is 520 feet long with a pressure drop of 0.3 inches of water column (w.c.) is based on several key factors, including gas flow requirements, pressure drop standards, and pipe sizing charts.

For gas distribution systems, the size of the pipe is critical to ensure that the gas flows efficiently from the supply source to the appliances. A longer line, such as 520 feet, will inherently experience a pressure drop due to friction and other factors. A pressure drop of 0.3 in. w.c. indicates that the gas pressure at the end of the line is still within acceptable limits for most appliances, but it is essential to size the tubing correctly to achieve this.

Using pipe sizing charts, which consider both the length of the run and the pressure drop, engineers and technicians can determine the appropriate diameter needed to keep the pressure drop within acceptable limits while allowing for necessary gas volume flow. In this case, the 1-1/2 inch size is derived from calculating the required volume of gas for operation at that length and pressure drop.

A smaller diameter tubing, such as 1 inch or 1-1/4 inch