I have added 2 symbols to plant3d 2012, On this line they are placed in 2 places, when the iso is produced one place comes out correct the other comes out wrong, I don’t know if I have done the symbols correctly so have attached images from the
It's not problem of symbol. This is the problem of 3D inserction. Your flange (or clamp) is insert in the first case Port1-Port2 and in the second case Port2-Port1. To solve this revise the connection settings.