Coperion improves tried-and-tested Standard Twin Screw Compounder

At Chinaplas (Shanghai, 18-21 April 2012),  Coperion GmbH  will be presenting its STS advanced series with various new and improved features. Two sizes of machine will be exhibited at Coperion’s Booth E1D31 in Hall E1. The STS 96 advanced compounder with 96 mm diameter twin screws is equipped with a new STS die head and a twin screw side feeder. This machine configuration is ideal for the compounding of engineering or biodegradable polymers or cable compounds. Typical applications for the STS 35 advanced, also being exhibited, are the development of products and processes in the laboratory and the production of a wide diversity of polymer compounds in small batches, such as color-masterbatches.

The STS advanced compounders cover all standard applications in the compounding of plastics. The modular design of the screw barrels and the screw elements permit process lengths of 24 to 68 D. Featuring five different machine sizes, the STS advanced series makes production throughputs of up to 3,800 kg/hour possible, depending on the actual compounding application.

Improved extruder die head, wear resistance and service

The new STS die head features an improved heating system and optimized flow geometry. Heater cartridges running transversely through the die head ensure a uniform temperature across its entire width. They are also distinguished by their long service life and extreme energy efficiency. The flow geometry has been improved in such a way that the rate of melt flow is uniform across the entire die head, thus ensuring that the individual strands discharge from the die head at the same rate – an important prerequisite for uniform strand pelletizing.

The process section of the STS advanced will in future offer a choice of materials featuring improved wear and corrosion resistance. A powder metal composite is available for the screw elements, while the screw barrel can be provided with oval liners in hard cast chromium steel. These materials have been thoroughly tested and are distinguished by their very long service life and high reliability in production.

At present, as many as 340 STS compounders are proving themselves in daily operation all over the world, around 60% of them providing service in the Asian-Pacific region and another 17% in America. A particularly successful year for the STS advanced was 2011; with almost 100 systems sold, the sales results again significantly exceeded the previous year’s figures.

In order to be able to provide an even better in-depth, requirement-oriented service – especially for its potential customers from the Asian region – Coperion will equip its test lab in Nanjing/China, with a new STS 35 advanced by July 2012. With this machine and the already installed STS 50, Coperion will then be able to offer its customers the ideal means of testing new formulations or screw configurations. The test results obtained can be reliably scaled up and applied to actual production requirements. So as to ensure an optimum service towards the compounding systems installed, last year Coperion increased its service team in Nanjing, China, to a total of 40 experienced service engineers.