Precision in pipe extrusion – the route to sustainability

The production of high-quality pipes was one of the highlights of the extrusion sector with many innovations presented during K 2025. Sustainability, precision, and high productivity serve as the targets of these breakthrough pipe extrusion technologies. KraussMaffei Extrusion presented its new 3-layer pipe head that enables the processing of 100% recycled materials; while SIKORA demonstrated the advantages of its measuring devices for improved precision and efficiency.

3-layer PVC pipe head meets demands of the circular economy

Sustainability is not just skin deep – it often begins underground: in our cities' pipe systems. This also applies to the production of PVC sewage pipes which has been the focus of KraussMaffei Extrusion’s latest 3-layer pipe head that allows the safe and stable processing of up to 100% recycled material. With this latest development, KraussMaffei Extrusion is sending a clear signal for greater resource conservation in pipe manufacturing while also meeting the growing demands of the circular economy.

New 3-layer PVC pipe head from KraussMaffei Extrusion enables safe and stable processing of up to 100% recycled material.

RK 42-HP is the result of a completely new development – not a further development of existing concepts, but a pipe head that has been redesigned and simulated from scratch. With a processing range of 400 to 1,200 kg/h and a diameter of 110 to 250 mm, it is ideally suited for large-scale industrial applications. "With the new KM-3L RK 42-HP, we highlighted the most advanced 3-layer pipe head for PVC applications. Our customers benefit from economical, sustainable, and outstanding quality pipe production," according to Ralf Benack, CEO KraussMaffei Extrusion.

At the heart of the new die head is a high-precision, patent-pending flow system with symmetrical material feed for all three layers. The solution for the core layer is particularly innovative. It benefits from a highly efficient 1-to-8 distribution, which enables extremely short dwell times and thus significantly reduces the susceptibility to errors. This allows 100% recycled material to be processed reliably, regardless of whether the layer is foamed or compact, and regardless of whether in-house recycled material or post-consumer waste is used.

The two cover layers are also characterised by maximum efficiency and flexibility. Currently, virgin material is predominantly used here, but the design is also suitable for the use of 100% recycled material.

The new KM-3L RK 42-HP enables manufacturers to produce much more economically. "Thanks to the largest process window on the market, long production runs with minimal downtime are possible. At the same time, material costs are significantly reduced," says Dr. Thomas Unger, Vice President Technologies at KraussMaffei Extrusion. And since material typically accounts for the largest share of operating costs, even small savings have an immediate and noticeable effect on the overall calculation.

Spiderlines—fine, unwanted marks on the inner wall of the pipe—can be virtually eliminated thanks to the new flow system. The optimised, even material flow in the pipe head prevents material accumulation and turbulence in the pipe head, ensuring a perfect surface without streaks.

The new pipe head also does away with chrome plating and double compression entirely. Avoiding chrome plating not only reduces manufacturing costs, but also significantly improves the environmental balance. Doing away with double compression geometry reduces the thermal stress on the material, simplifies cleaning, and enables quick tool changes in everyday production.

The new pipe head impresses not only with its technical performance, but also with its high level of maintenance and user-friendliness. Cleaning and product changes are straightforward, which in turn minimizes downtime. With the new KM-3L RK 42-HP, KraussMaffei Extrusion demonstrates how sustainable technology and the highest quality go hand in hand. The new pipe head makes it possible to manufacture durable and reliable infrastructure products from recycled PVC while increasing cost-effectiveness.

Innovative measurement systems for improved quality and efficiency

SIKORA, a manufacturer of innovative measurement, control, and sorting technologies recorded a significant increase in visitor numbers at K 2025 as compared to the 2022 edition. While most visitors came from Germany, there was also strong international interest, with guests from countries including India, Japan, and Turkey, showing great enthusiasm for the technologies on display.

SIKORA placed a strong focus on innovative technologies aimed at improving quality and efficiency, reducing material usage, promoting circular economy practices, and enhancing sustainability. The spotlight was on measuring devices for pipe, tube, and sheet extrusion, as well as inspection, analysis, and sorting systems for plastics production and processing.

One highlight was the CENTERWAVE 6000 radar system, a groundbreaking innovative key technology during the extrusion of big tubes. One or several transceivers, arranged around the circumference of a tube, for continuously sending and receiving frequency modulated millimeter waves measure contactless and µm-precisely the diameter, ovality and wall thickness of big plastic tubes during the extrusion process – without knowledge of material properties and without coupling mediums. CENTERWAVE 6000 precisely measures tubes and pipes with diameters ranging from 32 to 1,600 mm in terms of wall thickness, outer and inner diameter, and inner profile. The integrated “Dynamic Shrinkage Prediction” function allows for precise forecasting of the final pipe dimensions already after the first vacuum tank – a crucial advantage for early process optimisation.

THe PLANOWAVE 6000 system also attracted significant interest as the system enables precise and non-contact inline measurement of sheet thickness and density. The PLANOWAVE 6000 is used for a non-destructive measurement at the extrusion of plastic sheets for thickness measurement. The system is designed for measuring all plastic materials such as PE, HDPE, PP, PA6, PVC as well as glass fibre reinforced plastics. The PLANOWAVE 6000 is directly integrated into the production line or it is used for final inspection. The measurement of the sheet is accomplished by using millimeter waves according to the FMCW runtime method.  The AI-powered X-RAY 6000 PRO C-PIPEAI X-ray measurement system for dual-wall corrugated tubes and pipes, along with another X-ray-based solution for single-layer products, impressed the professional audience with their high performance.

One major attraction was the “Human vs. Machine” campaign, where visitors could bring their own pellets or test plates to be analysed with the PURITY CONCEPT V system. The analysis results provided valuable insights into material purity. Another crowd-puller was the PURITY SCANNER ADVANCED system. In a live demonstration, visitors were able to observe the inspection and sorting of pellets in real-time and experience the system’s efficiency first-hand. PURITY SCANNER ADVANCED is a powerful system that inspects plastic pellets in real-time using X-ray and optical technologies and sorts them with high precision. This is complemented by the PURITY CONCEPT V inspection and analysis system. Ideal for repeatable laboratory applications, it detects black and coloured contaminants as small as 50 µm as well as discolourations.

Ready for use in modern piping systems: the 3-layer PVC sewage pipes made from up to 100% recycled material

Holger Lieder, General Manager at SIKORA: “The response to our technologies was impressive – we were delighted to welcome not only familiar customers to our booth, but also to establish numerous new contacts. We are particularly pleased that we were able to discuss concrete projects that we will now pursue further together with our partners.”

There was especially high interest in the offerings of the SIKORA Academy, which provides hands-on training for the devices. These training sessions deliver in-depth knowledge for optimal usage and maintenance – an important contribution to increasing process reliability and efficiency while minimizing downtime.

A particularly significant highlight was SIKORA’s first public appearance under its new brand identity and as part of the MAAG Group. The repositioning was very well received by customers and partners and reflects both the company's technological advancement and its international growth strategy.