Depends on how and by who the families are made.
You should check your visbility graphics overrides of your elevation view.
I expect there will be a setting for something like "Elevation Swing".
Deselect that one and see if thos swing lines dissapear from your view.
Otherwise you will have to check the families and see how they are made and if those lines are in a separate sub-categfory you can switch of easily.
Louis
Please mention Revit version, especially when uploading Revit files.