In the course of an innovative partnership, the two well-known German machine building companies, Hans Weber Maschinenfabrik from Kronach and Leistritz Extrusionstechnik from Nuremberg, have implemented a trend-setting project in the field of pipe extrusion.
 
A great treasure trove of experience and the latest technologies, geared to the highest quality level, as well as highly motivated employees – these are the qualities that Leistritz Extrusionstechnik from Nuremberg and Hans Weber Maschinenfabrik from Kronach have in common. It is therefore not surprising that the two Franconian machine building companies are now cooperating to develop an innovative project.

Their customer clearly specified the requirements and tasks: the scope of project was a PP-3-layer pipe extrusion line, consisting of a main extruder (co-rotation twin-screw extruder) for the high-filled middle layer and two co-extruders for the inner and outer layer, as well as a multilayer head. The necessary production steps will be optimised, the production costs will be reduced and – obviously more importantly than ever today – there will be savings in CO₂ and energy costs. Moreover, a further objective was to be able in future to react immediately to possible changes in recipes or market requirements regarding the feed materials.
The set project targets do not pose a problem for the two Franconian machine builders.

The newly developed complete plant is equipped with a co-rotation twin-screw extruder type ZSE 60 MAXX made by Leistritz and two single-screw extruders type NE3.30, as well as a three-layer pipe head made by Hans Weber Maschinenfabrik. Combined with the respective gravimetric and dosing systems, this system offers clearly lower production costs for the customer.
 
Rather than two production steps (production of a compound (pellets) + pipe extrusion), Leistritz and Weber’s system requires only one single step thanks to intelligent in-line compounding. In this case, it mainly saves production time and CO₂ and as a result, makes for an important contribution to climate protection. The high percentage of calcium carbonate CaCO₃ or barium sulphate BaSO₄ for the high-filled middle layer is directly fed to the extruder by a gravimetric dosing system. A melt pump builds up the necessary and stable pressure of the melt.
The central line control is achieved by the control system OS5, made by WEBER. This ensures the integration of the downstream assemblies in a flexible and simple way.
The complete planning, project management and execution of this project has been in the hands of a team of experts with employees of the two machine building specialists.

The advantages at a glance:

• Flexible production
• Output of up to 650 kg per hour
• Better energy balance
• CO₂ saving
• Saving in production costs
• Production of pipes with a diameter of 40 - 160 mm is possible