Sand packs are characterized above all by high melt homogeneity and are therefore particularly suitable for virgin mate-rial. Packages with filter candles, on the other hand, offer a larger filter area and were originally developed specifically for recycling applications. The increased filter area improves filtration perfor-mance and extends service life but is also associated with a lower flux rate and shear, which can have a negative effect on homogeneity.

In the new ValuePack spinning package, BB Engineering combines both approaches — metal sand and filter cartridges — in a two-step filtration process. The melt first flows through the filter cartridge, where it is efficiently filtered down to 15 μm across a large filter surface area. It then passes through the sand chamber, where ho-mogenization and shearing in particular take place. The concept is as simple as it is innovative and offers clear advantages. It results in significantly improved homogeneity in terms of temperature and viscosity, better spinning performance, and higher yarn quality. This added value is particularly evident in recycling processes, where it enables the production of higher-quality products. Furthermore, the ValuePack’s two-stage filtration can also offer advantages in other demanding or quality-critical applications.

Another advantage of the ValuePack is its pressure-independent seal. This helps prevent leaks, which can occur with self-sealing packages. At the same time, this allows for a wider process window. Existing systems can be easily retrofitted to accommo-date the ValuePack, which is slightly longer due to its design.

With its multi-stage filtration in the spinning package, BB Engineer-ing plays a pioneering role and, underscores its expertise in the field of synthetic fiber spinning and recycling. At the ITM trade show, vis-itors were able to experience how the ValuePack works through an impressive VR animation.