FROM FLAWS TO FLAWLESS: ADVANCING PACKAGING QUALITY

In this project, born to solve a problem on a Japanese injection moulding machine from a leader on the international market, we once again worked solely on the design of the screw; eliminating the need exposed by other competitors of having to change the entire plasticizing unit.

The problem arose on transparent pieces produced with a sandwich-type mould and an original plasticising unit equipped with a barrier screw used to process PP to which, due to contractual terms, costumer had to add a 1.5% clarifying additive in order to guarantee the excellent transparency of a the cover for sweets box from a globally famous brand. The defects on the moulded pieces concerned the need to eliminate whitish streaks/veins which, obviously, made the product totally unacceptable by mould owner.

Problem to be solved:

• Coloured Streaks

Plus desired but not imperative:

• Improve cycle time

Solution:
After carefully checking the original screw design characteristics and plasticizing cycle time parameters we proceeded with a complete design modification, changing the shearing gates of the barrier, the pitches and adding a mixing area, basically creating a customized HPB – MIXING design.

What we reached:

• Resolution of product non-compliance due to streaks
• Consequent improvement in the level of transparency
• Feeding time reduced by 30%
• Improvement in total cycle time between 9 and 11%