Disappearing tanks in Ortho View

[ugurbalbay]

Dear All,

I have a very strange problem while I wanna get ortoghraphic view from the tanks that I draw by using the create equipment button ( Class is tanks) from the autocad plant 3D menu.

I can see all tanks that I draw in the 3D model,

I can start piping over the nozzles

I can move or hide the tanks

I can see the tanks in the database as tanks

I can see the tank in the isometric drawing as connected

I can also save the tanks as .peqs format.....  but:

I can not orbit the all 3d model if I see tanks in my screen'

I can not select the tanks if I not click onto the one of nozzles'

I can not EXPLODE the tanks into the blocks from the equipments.

I think that maybe I did a mistake but I started over again and it seems as it before!

I think this is like a bug or another problem I have in my drawing file. Because I checked the layers and view options.

If anyone can help me it would be perfect.

Best Regards...