Preforms: injection-compression is here

With the Xtreme brand machines, Sipa SpA presents a new technology for the production of preforms from granules.

With the Xtreme brand machines, Sipa SpA presents a new technology for the production of preforms from granules. Alternative to injection molding, injection compression is thus called because it proceeds with the injection of PET into the mold cavity, and then with the dosage and compression, enabling very thin gauges (0.8-1mm) to be attained.
As Roberta Gualtieri, Sipa marketing manager explained - Xtreme opens up endless possibilities. The injection-compression not only allows the minimum thickness limit of traditional injection procedures to be overcome, safeguarding the mold from premature wear caused by very high pressures, it also enables working on previously inaccessible areas of the neck and base, attaining unusual shapes and stretch ratios unimaginable up to now (weight/length 80:1; against 45 of traditional processes), this in all directions.
Important too the economic advantages. With Xtreme - which produces 50 thousand preforms per hour - the product process management costs (among other things 10% less energy is used) are drastically cut, the overall dimensions of the system also being reduced: The 72 cavity version takes up only 34.5 square meters or 30% less space than the most compact Sipa injection molding machines (Xform).

Facts and figures. Xtreme enables the attainment of preforms that are 10% lighter, with a working cycle 5 times faster, and an opto-electronic quality control of 100%. With this technology you get bottles of 500 ml only weighing 5g, ideal for making containers up to 1.5 liters while attaining 2.5 liters without problems; it can also produce two different types of preforms simultaneously, adding new elements of flexibility to those already ensured by rotary technology due to the absence of hydraulics (all the valves are pneumatic) and by the single compressional bars, that are replaced one at a time. This element, in particular, has revolutionized job change operations: a 72 cavity mold is replaced in 45 minutes, or one quarter of the time of a conventional injection molding machine, and without any particular effort.