6% higher OEE: Wavin stabilizes processing recycled material via Injection volume

Extreme weather events are increasingly pushing urban drainage systems to their limits. As a global leader in water and climate management solutions, Wavin addresses this with modular rainwater storage systems such as AquaCell and Q-Bic+, which pick up, temporarily store, and control the discharge of water.

These components must withstand high mechanical loads, for example in accessible Zones for pedestrians or vehicles. They are therefore produced from high-performance compounds.

The sustainability approach is consistently applied to the products:

• AquaCell is made exclusively from recycled Polypropylene

• Q-Bic+ is also available with a very high recycled content

When processing recycled plastics, the injection volume is a particularly critical process parameter. It influences component quality, dimensional accuracy, and process stability. Wavin was confronted with these process-related requests.

Recycled materials are a central component of sustainable, eco-friendly plastic products. However, they pose particular challenges for injection molding.

Not all recycled materials are the same: Depending on origin, processing, and batch, material properties such as plastic material viscosity, flow behavior, or moisture content can vary significantly.

Since Wavin is working with up to 100% recycled plastic in some of its production processes, fluctuating viscosities are unavoidable.

Such material-related fluctuations have a direct impact on the injection molding process:

• fluctuating part weights

• unstable process windows

• increased rejects

• additional effort by means of manual corrections

Against this background, it is crucial to specifically compensate for material-related fluctuations in the injection molding process. The injection volume becomes the central control parameter for reliably processing different recycled material batches.

By automatically compensating for recyclate-related deviations in injection volume in real time, consistently high quality can be achieved despite varying recyclate properties. This reduces the increased effort required for manual readjustments, minimizes rejects, and improves OEE.

iQ weight control is a digital assistance system from ENGEL that automatically adjusts the injection volume shot by shot. It is based on the continuous evaluation of relevant process data, including plastic material viscosity, filling speed, and Pressure profile. The system detects deviations early on and adapts the injection volume directly in the next cycle.

Wavin benefits from:

• consistent parts weights

• consistent quality despite raw material fluctuations

• low operator intervention

• a robust process also during recycled material batch changes

Thanks to digital process control, viscosity fluctuations in plastic recyclates can be effectively compensated for, ensuring reliable and reproducible production of heavy-duty, sustainable drainage components.

“iQ weight control helps enormously to compensate for material differences and keep the process stable.” (Eddy Gerritsen, Injection Molding Manager at Wavin)

To efficiently and reliably manufacture sophisticated, technical plastic components for water management, Wavin has relied on ENGEL machine technology at its Hardenberg location for over 30 years.

For the production of small and medium-sized parts, Wavin relies on ENGEL victory machines with a tie-barless design, which are particularly impressive due to their flexibility and efficiency:

• high mold accessibility

• fast mold change

• simplified automation

For large-volume components such as AquaCell, ENGEL duo two-platen machines are set to be used:

• The duo 2700, with a clamp force of 27,000 kN, ensures the necessary precision for 15-kg components.

• Thanks to the machine’s consistent performance since commissioning, the production process remains reliable even with large, delicate parts.

• System availability is a critical factor for large components, as downtime is particularly costly in this context.

The combination of high-performance injection molding machines with large mold areas and digital assistance systems such as iQ weight control ensures stable processes, fast cycle times, and reproducible results – regardless of the material.

Wavin has made the effect of the implemented solution measurable: OEE was increased by 6%.

The key to this is the targeted stabilization of the injection molding process via precisely controlled injection volume per cycle. This is also maintained at a constant level even when recycled material properties vary.

The lever behind this acts on several levels:

• Reduced rejects, as consistent shots and uniform part weights are reproducibly reached

• High machine availability and power, as less malfunctions, less rework, and significantly less standstills occur

• Recycled material is no longer a risk factor, but a fully controllable standard material

For Wavin, the solution contributes to several aims at once:

• sustainability by means of recycled plastic

• process stability despite fluctuations

• cost-effectiveness through OEE improvement

• planning reliability for large-format parts

In short: Thanks to automatically controlled injection volume, iQ weight control not only has a positive effect on part quality but also specifically helps improve OEE, thereby sustainably increasing production efficiency.