How many bar of pressure to lift 1 ton?

First, you will have to convert the ton to units of force (about 10,000 Newton). Second, to convert the pressure to force, use the definition of pressure: pressure = force / area. In other Words, the pressure required will also depend on the area over which the pressure is applied.

Note

1 bar = 100,000 Pascal

1 bar = 100,000 Newton/m2