Are there any way of deleting or temporary hide all lines on surfaces?
Select the edges you want to delete or hide and delete them or hide them. If those edges are required to support faces, deleting them will delete the faces, too. Hiding or maybe softening would be the appropriate choice then.
Thank you but that is a non working solution, taking on each line at a time. Hundreds. Also sorry for my rough description - it should have said lines on non support faces, I will see if its possible to update the headline.
Attach an example so we can see what you are dealing with.
I didn’t say anything about doing them one at a time.
As Box wrote, attach an example.
You can make a group and then delete the group. That keeps the edges that are binding other faces.