Leistritz expertise at Achema 2018

The smallest Leistritz extruder: ZSE 12 HP-PH (Image: Leistritz)

The Leistritz Rheometer with patented nozzle geometry – closed and open. (Image: Leistritz)

The Leistritz Rheometer with patented nozzle geometry – closed and open. (Image: Leistritz)

Leistritz Extrusion Technology GmbH will showcase products for both Pharma/Life Science and the plastics industry from June 11 to 15, 2018 at Achema (Hall 5.0/Stand D59): the ZSE 12 HP-PH twin-screw extruder as well as the new Leistritz Online Extensometer for intelligent process monitoring.

The Nuremberg-based Leistritz Extrusion Technology presents itself at Achema with a double feature, displaying products from the Pharma/Life Science and plastics sectors. "In our luggage, we have our smallest twin-screw extruder, a ZSE 12 HP-PH, as well as our new Leistritz Online Extensometer," explains Albrecht Huber, Head of the Life Science/Pharma Product Division at Leistritz. In addition to the exhibited products, attention will also be paid during the five days of the fair to further auxiliary units such as side feeding and degassing, as well as the expanded service portfolio of the extruder manufacturer.

ZSE 12 HP-PH

With a throughput of 50 to 1,000 g/h, the ZSE 12 HP-PH is ideally suited for R&D. Depending on requirements, the production of clinical batches is also possible. When designing the ZSE 12 HP-PH, particular attention was paid to ease of handling, simple (dis-)assembly, and good cleanability. In addition to its mobile design, the machine features a foldable cylinder that provides insight into the process. "An important topic we addressed was temperature control," says Albrecht Huber. "We developed an innovative concept that has not been available in the pharmaceutical sector until now." This allows eight individual heating and cooling zones to be regulated, with temperature sensors included. The temperature control can be built into or removed from the cylinders using a simple clamping system. "Another highlight is a powerful drive unit," explains Huber. The torque of 20 Nm ensures stable operation under various process conditions and facilitates scale-up to the next machine size. Ultimately, the geometric properties of the ZSE 12 HP-PH match those of larger production extruders. The system is rounded off with a modern PLC control with a large touch panel.

"Like all other Leistritz extruders, the ZSE 12 HP-PH can be used for various processes, including melt and lipid extrusion as well as wet granulation. Our experience in process engineering, materials technology, and qualification is particularly valuable here," states Albrecht Huber. Leistritz's granulation systems can operate standalone or be integrated into continuous manufacturing systems, such as in cooperation with GEA (Hall 4.0/Stand F46).

Online Extensometer

In collaboration with Johannes Kepler University in Linz, Leistritz has developed an online extensometer with a patented nozzle geometry. Its application range covers all plastics and supports process safety both when processing highly viscous pipe compounds and when manufacturing low-viscosity products for fiber and injection molding applications.

During the extrusion process, part of the melt flow is diverted via a bypass system and directed through the rheometer's slit nozzle. The nozzle is based on a new, patented geometry featuring a hyperbolic constriction. The system subsequently allows the material to be returned to the main process, preventing material loss.

The rheometer enables online measurement of shear viscosity at shear rates from 10 to 10,000 s^-1 and elongational viscosity at strain rates from 5 to 75 s^-1. The innovative nozzle geometry produces a constant elongational flow, which was not possible with previous online measurement devices. During continuous measurement, users can simultaneously query two shear viscosity values and one elongational viscosity value within precisely defined shear/strain rate ranges. Intelligent automation in the control of the online rheometer allows users to quickly obtain viscosity curves of the currently produced material by targeted variation of shear and strain rates. Additionally, the melt flow index and IV value can be displayed. The online determination of melt density complements the extensive analysis capabilities.

Mechanically, the new online extensometer can be integrated into any extrusion process easily and without major modifications. The software and visualization of measurement results are either part of the Leistritz extruder control system or available as a separate stand-alone version.

Auxiliary Units

Over recent years, Leistritz has consistently optimized all assemblies for its ZSE MAXX twin-screw extruders to meet customer needs. In this context, particular focus has been placed on the further development of the side feeding LSB XX and the side degassing LSE XX.

The LSB XX impresses with the high Da/Di ratio of 2.0 of its side feeding screw. This allows materials with low bulk densities to be added easily. The screws are segmented and thus adaptable to the process. To handle low-melting-point formulation components reliably, there is an option to cool the side feeding screws from the inside. The LSE XX also features a large free volume and promotes optimal degassing of the polymer melt. The cylinders are heated with heating cartridges. Overheating of the gearbox is prevented by the cooled gearbox housing. The LSE XX is available as a horizontal version on a base frame or as a vertical attachment directly on the process section. Retrofitting is always possible.

Expanded Service Portfolio

The development of service offerings goes hand in hand with the development of modern extrusion lines. Therefore, Leistritz has expanded its portfolio with several attractive after-sales solutions. At Achema, the service team of Leistritz Extrusion Technology GmbH will showcase, in addition to standard offerings, Industry 4.0 solutions and "Smart Services." Interested visitors can learn about the added value for customers directly at the Leistritz booth.