Add valves.
Part Insertion panel
Spec Viewer. 
Part Properties
Valve Operator. 

Part Properties
Valve Operator.
In the Operator box, click the valve operator override button. 



When you are tracking over a piping component, attachment port and insertion point options display on the command prompt.
If No Endpoint Found for Specified Point displays when using the Near object snap, you can increase aperture size or zoom out. To snap correctly, the Nearest osnap glyph must be visible when the mouse is directly over the pipe centerline.



