A machine for expanding plastic parisons into plastic containers by a liquid medium with at least two transforming stations. These transforming stations fill and expand the plastic parisons with the liquid medium, with at least one pressure generating device. This pressure generating device is suitable and intended to deliver the liquid medium to at least one filling device which fills the plastic parisons with the liquid medium, wherein at least one shut-off device is installed in at least one connection channel between the pressure generating device and the filling device, inside which the liquid medium is conveyed. This shut-off device is configured and provided in order that a fluid path inside the connection conduit can be at least partially interrupted.