This page contains a Flash digital edition of a book.

off via a by-pass system and pushed through the rheometer’s slot die. This die is based on a new, patented design with a hyperbolic narrowing. After the measurement, the material is transferred back into the process without losing any material. The rheometer facilitates online measuring of

Above: Leistritz’ smallest twin-screw compounder, the ZSE 12 HP-PH was originally

developed for pharma applications

Consultants. “The voice of the customer has told us that small lots of materials are key, they are what they want and need to develop their businesses – and they want and need them fast. REV Materials is working to dominate this small lots niche.” Entek’s recent development of its QC3 (Quick

Change, Quick Clean, and Quality Control) twin-screw extruder technology is said to fit the REV Materials business model perfectly. Only one thing was missing: the best sized machine for the operation. “We approached Entek asking them for something they didn’t have – a 33mm twin-screw extruder,” said Cernohous. “We wanted a custom- developed machine that was ideal for producing small lots, fast.”

Right: The new inline elonga- tional rheom- eter from Leistritz shown with the front cover removed

Inline rheometry A novelty introduced by Leistritz at Fakuma this year was its inline Elongational Rheometer. The company had flagged up its development activities in this area at the K show last year but this was the first public showing of the measurement technol- ogy, which provides data to identify even the slightest variations in the compounding process, the company claims. “As part of the continuous development of process technology and Industry 4.0 activities, Leistritz paid close attention to the important issue of an intelligent process control,” says Leistritz Managing Director Sven Wolf. The rheometer has been developed in

cooperation with the Johannes Kepler University in Linz, Austria. The range of ap- plications is said to extend to all plastics and supports process reliability when working with both highly viscous pipe compounds as well as low viscous products for fibre and injection moulding. During the extrusion process, a small amount of the melt flow is channelled

22 COMPOUNDING WORLD | December 2017

the shear viscosity with shear rates in the range of 10 to 10,000/s and the elongational viscosity with elongation rates in the range of 5 to 75/s. The die generates a constant elongational flow. So far, this has not been possible with current online measure- ment devices, Leistritz says. During a continuous measuring process, the operator can query two measured values of shear viscosity and one value of extensional viscosity in the according, precisely defined shear and expansion ranges at the same time. An intelligent automation in the online rheometer’s control unit allows the user to obtain viscosity curves of the material being currently processed within a very short time. This is accom- plished through targeted variation of the shear and elongational rates. The rheometer can also indicate the melt flow

index as well as the IV value and melt density. It can be mechanically integrated onto any given extrusion process, without having to undergo major retrofits. The software and visualisation of the measured results is either part of the Leistritz extruder control unit or via a separate stand-alone control.

Repurposed from pharma Leistritz also highlights the availability of its smallest twin-screw compounder, the ZSE 12 HP-PH. This was actually designed for the pharma- ceutical sector, the company says, but when it was shown at K last year caught the eye of plastics R&D visitors. “The ZSE 12 HP-PH twin screw extruder offers sophisticated features, which makes it a perfect R&D machine,” says the company. “Additionally, it has all machine characteristics that are necessary to facilitate scale-up to larger extruders.”

The unit, which has a throughput of 50 to 2,000 g/h, was designed as a mo- bile plug&play solution. It comes with what Leistritz says is a unique and innovative C profile for the barrels to satisfy demand for easy cleanability and assembly/disassembly. On the one hand, it ensures that the hinged barrels are tight; on the other hand, all relevant media connections for heating and cooling of the processing unit are integrated. There are eight



Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78