51 are disposed at the side of the perforating element 5 in fig3 these are fixed relative to the upper die carrier 13 so that the perforating element 5 can also be displaced relative to the lateral perforating elements 51 in the direction described above a counter support 11 is disposed in the area between the two molding rings 17 in the lower die opposite to the perforating element 5 it cooperates with the perforating element 5 and if necessary lateral perforating elements 51 upon the introduction of the mechanical weakening in the lid element 39 a clamping frame not shown is also disposed on the upper die carrier 13 which fixes the sheet shaped starting material in the thermoforming die by means of a counterpunching plate also not shown in addition to this function as a clamping tool the counterpunching plate has the further function of acting as a counterelement to the circumferential cutting edge 47 of the cutting knife 15 in order to make a punching out of the lid element 39 formed between the upper die and the lower die from the sheet web material possible the counterpunching plate is disposed on the lower die carrier 12 two molding rings 17 are so to speak disposed on the carrier 1 of the lower die which mold parts of the subsequent inner contour of the lid element 39 to be produced they have in each case a recess within which a mold bottom 18 a b is disposed the mold bottoms 18 a b have the function of molding parts of the inner area of the lid element 39 and after the implemented molding of ejecting the produced lid element 39 from the.