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The NNPB process is mainly used for lighter containers such as beer bottles, small water and juice containers, and other lightweight containers. It is the most advanced forming process because it yields not only the highest machine speeds but also a homogeneous glass distribution in the final container. It is similar to the PB process in that the gob is not blown into the parison but pressed via a plunger. After loading the gob (Figure 6), the mold is closed fully by the baffle and a plunger smaller in diameter than in PB presses in an upward movement the glass into the mold (Figure 6b). The plungers are also made out of tungsten‐carbide. As with PB, the finish is formed at the end of the blank‐mold process (Figure 6c). Again, the baffle is removed after the parison has been formed, the mold opens (Figure 6d), and the parison is transferred to the blow‐side.

Figure 5 (a–d) Press & blow process, blank‐side.

Restrictions in usage of the NNPB process are due to the plunger dimensions and finish openings and the corresponding cavities pressed into the parison. The parisons are usually shorter for NNPB than for BB if the same final container shape is to be produced (e.g. a 0.33 l beverage bottle). Another significant difference between NNPB and BB is that the required gob temperature is from around 20 to 50°C higher in NNPB because of difficult pressing conditions. This difference in consequence leads to different thermal requirements during the process in terms of mold‐cooling and reheat‐timing.