Winkworth claims hygienic mixer/extruder is a ‘world first’

01 May 2020

Winkworth, a leading designer and manufacturer of industrial mixing and blending machinery, believes it has developed the world’s most hygienic kneader mixer extruder machine to suit the most demanding application requirements.

As part of an intensive three-year design programme, the Hampshire-based company has manufactured a reliable, high-powered compact mixer extruder machine that can be fully integrated within ancillary equipment. The machine is also free from cross-contamination.

A high level of automation is required to cover the full control of the mixing process, precision and control of the blade and screw speeds, full integration with inlet systems, mixing durations, vacuum levels and duration, temperature control, zone management during mixing and, critically, during discharge.

“Machine cleaning requirements vary from machine to machine and applications, some permit wet washing and CIP (cleaning in place) approaches, while other strictly forbid liquids,” said Winkworth’s managing director,” Grant Jamieson.

“Designing and building a machine as complex as this was a challenge, but with the product to be mixed ‘sticky’ by definition, this added a further challenge due to the strictly ‘no liquids’ cleaning procedure.”

Despite the need for all product contact services to be cleaned between formulas, downtime due to cleaning had to be minimised. To meet this requirement, the machine has been designed to the latest pharmaceutical more stringent Good Manufacturing Practice (GMP) standards, though similar to the European Hygienic Engineering and Design Group (EHEDG), which supports a simple yet effective independent verification of ‘clean'.

Providing access to allow ergonomic safe cleaning behaviours was critical; the human factors reach, touch, line of sight, lifting, pulling, pressing and trip hazards were all considered. Therefore, the machine had to be retractable to provide access to the kneader blade. Simultaneously, the extruder screw is retracted, which provides full 360° access to the screw itself.

Meanwhile, a pivoting, hinged, non-drive end door to the mixer chamber provides access from the end of the mixer chamber and full access to the inside surfaces. Closure after cleaning and inspection is an automated reversal of opening, allowing for a fast and verifiable process that promotes high levels of productivity.

The operation is fully automated using electrics, hydraulics, pneumatics and optical control sensors with safety guards, incorporating proximity sensors, fitted to verify safety systems are intact.

“I'm very proud of the quality demonstrated throughout this project and the strategic relationship we have developed with our client,” added Jamieson. “The machine is state-of-the-art and houses several innovative design features ensure performance and hygiene. It has an unprecedented amount of automation too, which means it is capable of being cleaned in a fraction of the time when compared to similar machines. It will provide our clients with a totally dependable solution for decades to come.

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