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There is a well-known rule of progression when it comes to cavitation in medium and large-sized PET preform molds: 72, then 96, 128, 144. But SIPA thinks some rules are made for breaking – especially when it means its customers can optimize the output/capital ratio!

SIPA has demonstrated on numerous occasions that, with some very clever hot runner configurations and ingenious tool engineering, it is perfectly possible to squeeze more cavities into a given mold space, with absolutely no loss of preform quality.

Unconventional cavity numbers for better output/capital ratio

Think about a “workhorse” 72-cavity mold: this is considered a good choice for low-to-medium output production on a 250-tonne machine like SIPA’s XFORM 250. But what if you could give yourself an important incremental boost, without having to invest on a bigger tooling (i.e. 96 cavities)?

SIPA has the answer. It has developed an 84-cavity mold for the XFORM 250 platform. This unconventional mold provides a significantly better output per capital ratio than a 72-cavity mold – something like 13% better in fact, when producing preforms for 1.5-L bottles on the same SIPA machine – and well ahead of what is possible on rival 72-cavity machine/mold combinations.

XFLOW allows consistency and reliability

Creating a hot runner system that consistently and reliably enables more cavities to be filled identically, at high speed, without excessive force, is a task that extremely few companies are capable of handling. SIPA can do it, thanks largely to its Xflow melt distribution system.

Xflow incorporates an innovative hot runner manifold design that provides the best balance of melt distribution in the industry. In fact, it exhibits the lowest pressure drop ever measured.

This technology, unique to SIPA, allows the company to create very high-cavitation systems without having to compromise on balance, pressure losses, and the formation of acetaldehyde due to polymer degradation.

Cost-effective unique solutions for high productivity

The unique engineering solution applied to 84-cavity molds has already been widely proven by SIPA when introducing the world’s first 180 cavity injection mold and which has since then become one of the company’s bestsellers to run on XFORM 500 systems that would normally be acquired to run with 144-cavity molds.

The world’s first 200-cavity preform mold makes it possible to produce over 130,000 preforms every hour, making the investment in an XFORM 500 production system even more cost-effective than ever. It is just what major packaging companies are after: with a single system producing more preforms, they can cut consumption of utilities, be more efficient in the use of labor, and tie up less valuable floor space.

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