Method and apparatus for forming plastic preforms for plastic containers with curve evaluation

Method for forming plastic preforms into plastic containers, wherein a plastic preform is introduced into a blow mould and is expanded into a plastic container by being applied by a flowable medium, wherein the plastic preform is applied by at least two different pressure levels and wherein furthermore preferably a rod-like body is introduced into the plastic preform, in order to expand the plastic preform in its longitudinal direction, wherein a pressure curve and/or a movement curve of the rod-like body being determined by a measuring device during the expansion process, wherein least one of the curves is evaluated by means of a processor device and at least one point or region of this curve which is characteristic of the course is determined.