STS Mc¹¹ extruder for economical masterbatch production

Bruno Peter AG, based in Büren an der Aare, Switzerland, is expanding its production facility to include an STS 35 Mc¹¹ twin screw extruder. With its screw diameter of 35 mm, this extruder is ideally suited to the requirements of the company Bruno Peter AG, which is furthering its development and production of high-quality color and additive masterbatches and compounds based on an additional production capacity of up to approx. 650 tons per year. Coperion has designed the STS Mc¹¹ extruder with a variety of solutions intended specifically for the economical production of masterbatch in small to medium batch sizes. The STS 35 Mc¹¹ extruder is currently being installed on the premises of Bruno Peter AG in Büren an der Aare, where production will soon commence.

Ease of cleaning for quick recipe changes
In addition to the attractive price/performance ratio, the design of the STS 35 Mc¹¹ extruder was also a deciding factor in securing the order from Bruno Peter: The system’s features ensure very simple handling and ease of cleaning. Both the water manifold and all wired connections are incorporated into the base frame. This setup ensures smooth surfaces and makes it easier to clean without hindering accessibility. The protective cover of the STS Mc¹¹ can also be easily cleaned thanks to its special, gapless design and smooth surfaces. It ends directly at the extruder’s base frame and gives operating personnel easy access to the process section when needed. Coperion has equipped the feed barrel of the STS 35 Mc¹¹ with an exchangeable sleeve insert that facilitates cleaning and faster product changes. All in all, these features ensure the economical production of high-quality masterbatches with a throughput rate of up to 300 kg/h.

The STS 35 Mc¹¹ also satisfies the requirements of Bruno Peter in terms of the discharge. Coperion has equipped the system with a die head that was particularly developed for masterbatch processing. The die head can quickly be opened and cleaned just by loosening two screws, which makes for rapid product change. The flow geometry of the die head has been optimized through FEM calculations, ensuring homogeneous discharge with minimal dead space – even for highly filled products. The quick-release die head also enables a rapid conversion from strand to underwater pelletizing operation.

Thomas Peter, Managing Director of Bruno Peter, is convinced that his company made the right choice in procuring the STS 35 Mc¹¹: “With the STS 35 Mc¹¹ twin screw extruder from Coperion, we have opted for a solution to expand our production capacity that can be seamlessly integrated into our order structure. When manufacturing masterbatches, we need to react to recipe changes increasingly quickly and quick product changes are crucial for being able to produce economically. Here, the STS 35 Mc¹¹ offers us the best conditions at attractive investment costs.”