Tetra Pak Carton Chilled Inc., Minneapolis (tetrapakusa.com), recently introduced a new Gable Top Liquid Carton filling machine that incorporates cleandesign pneumatics to ensure washdown resistance, efficient operation, and low maintenance.
The Tetra Rex TR/17 ESL fills Tetra Rex gable-top cartons with dairy products and juices. The machine reportedly offers advantages over competitive models, including the ability to fill several different carton sizes, hygienic design, and cleaning refinements that minimize bacteria contamination during and after filling. This enhances quality and helps extend the shelf life of chilled liquid products.
The machine is designed with a sloping tabletop that improves water drainage after frequent cleanings. Generally, packaging machines are constructed of "right-angle" components that harbor microbes in crevices. But the new TR/17 ESL uses slopes and angles to promote runoff and discourage bacterial growth.
An operator loads carton blanks and directs the machine using a touchscreen panel to automatically open, sterilize, fill, and seal cartons. Pneumatics handles the cartons, opens and closes process valves for filling and cleaning, inserts caps, and drives linear actuators for motion control. A DeviceNet fieldbus connects electronic controls, pressure switches, valves, and position sensors, and offers easy-to-decipher diagnostics.
The easy-to-clean concept was a key consideration when selecting the pneumatics. Festo Corp., Hauppauge, N.Y. (festo.com/us), together with Tetra Pak, developed the CDVI valve manifold that permits quick and easy washdowns and prevents contaminants from sticking to the machine.
Pneumatics was chosen over an electromechanical system because of economics and performance, according to Tetra Pak officials. Earlier machines experienced contaminated solenoid coils during washdowns, causing product contaminationand an unacceptable rate of valve failure. The CDVI prevents these problems because the valve and coil are encased in a plastic shield with no exposed metal parts.
The design includes no sharp edges, small radii, or crevices where dirt can gather, and enough space between valves to make cleaning easy and let water and other liquids run off rather than pool. The unit conforms to IP65 and IP67 protection standards with a polypropylene housing, anodized aluminum base plate, stainless-steel fasteners, and EPDM seals, together with a chemical-resistant multicore cable.The CDVI offers 5/2, 5/3, and 2
33/2-way valve functions. Terminals can be extended by adding two valve positions at a time up to a maximum of 12 positions at three different supply pressures. The design is also aesthetically appealing, say Tetra Pak officials.