Click
Gas tab 
Gas Distribution panel, and use the tools to create Gas pipes, fittings, and valves.
If the features you want to create are not available on the Gas Distribution panel, use the Feature Library or Model Viewer in the Design Explorer. For more information, see About the Feature Library and About the Model Viewer.
You can lay out a gas pipe independently or add it to existing segments as needed. For more information, see To Add Ducts and Conductors to an Existing Segment.
Note: As you create features, be sure to maintain connectivity to avoid validation issues. The Connected To icon helps identify features for connection. For more information, see
About Connection.