Cleanliness is often considered a virtue. In the beverage packaging industry, it's an absolute necessity. That's because in the dairy and juice industries, machines are washed down constantly to avoid contamination. Equipment is subjected not only to water, but also to chemical cleaners and sodium potassium hydroxide. Because of the minimal risk of contamination, pneumatics is a very clean technology and the first choice for many food and packaging companies. Pneumatic components withstand even the toughest environments, with a long life expectancy due to their simple design and few internal parts.

For one beverage packaging OEM, Evergreen Packaging of Cedar Rapids, Iowa, using washdown-duty pneumatic components turned out to be the best strategy for avoiding contamination and reducing downtime. The company recently developed an economical gravity-fill bottle filler that uses washdown pneumatic valves from Bosch Rexroth Corp., Lexington, Ky. Suitable for water, juice, dairy, and other beverages, the Evergreen BFCG-32/16 provides high output and the versatility to handle a variety of liquid food products with at least 95% efficiency.

Using 32 fill heads and 16 capping heads, the small-footprint rotary machine takes up just 47.5 sq/ft. and fills up to 400 bottles per minute. Externally demountable, no-drip fill nozzles require a minimal amount of pressure to actuate, dramatically reducing bottle wrinkling and product waste. With a special focus on cleanliness, Evergreen offers extended life options including HEPA, auto sanitize, and full clean-in-place (CIP) capabilities.

To help avoid contamination and reduce downtime and maintenance costs, Evergreen specified IP69K washdown-duty CL03 pneumatic valves from Bosch Rexroth. The valves are used to control the filling process and the integrated sanitation and clean-in-place system. To meet the IP69K rating, valves must withstand high-temperature water with 1,450 psi at a distance of four to six inches while being rotated between 0, 30, 60, and 90° angles.

Bosch Rexroth designed the CL03 in cooperation with food and packaging end users and OEMs in Europe and the U.S. Based on OEM input, the company designed a product with smooth corners and drainable surfaces, strong fiberglass reinforced polyamide 12, stainless steel hardware, positive joints to avoid material buildup, and HNBR seals between the valve cover sub-base and sub-plates. Stainless steel cabinets traditionally needed to house the valves are eliminated; mounting valves closer to actuators minimizes air-line lengths and reduces air consumption costs. Placing valves closer to actuators also reduces cycle time, increasing productivity.

Tim Hughes, director of engineering at Evergreen, believes that using pneumatics is an advantage due to low maintenance costs. “In the dairy and juice industry, you can't afford to have a production line down,” says Hughes. “Stores get milk shipments every day, so avoiding downtime is critical. Dairies survive on very low margins. If they have high maintenance costs for keeping a piece of equipment going, that comes out of the profit margin. The beauty of pneumatics is that they're easy to troubleshoot without downtime being an issue.”