Liquid filling machine trends: Today's equipment is more versatile

A walk down the grocery store aisle will exemplify the overwhelming amount of beverage products to choose from these days. Even with the existing wide variety of flavors and concepts within each drink category, consumers seem to want even more. For example, one of the fastest-growing segments in the beverage industry continues to be craft beer. Even after the beginning of its meteoric rise a few years back, the number of specialty beers with unique ingredients and different styles continues to proliferate with other craft alcohol producers, such as cider and spirits, following close behind. To keep up, many facilities are designing and installing additional liquid filling lines.

“As product lines continue to evolve to match expanding consumer demands, manufacturers are seeking flexible equipment that allows for product modifications—without breaking the bank,” says Paul Grainger, technical key account direct or North America for Tetra Pak. “Today’s equipment simply must be designed to accommodate a diverse range of products in order to be viable.”

Additionally, to maximize production efficiency, many are turning to high-capacity and more automated equipment that provides this flexibility. Still top of mind, though, are accuracy, minimizing product waste, reducing changeover times and simplifying sanitation. Liquid filling equipment providers are working to meet all these needs and more.

Designing a filling line: Product is king

When picking a specific filling machine, a good place to start is to know the exact characteristics of the liquid product. Is it a free-flowing liquid? This might work better with a timed-flow fill machine where the same volume of product is delivered each cycle. What if the product is more viscous? For that, a positive displacement liquid filler might be the way to go.

“Product specification is the most important parameter that we, at Bosch Packaging Technology, need in order to identify a suitable piece of filling equipment for our customers,” says Jonathan Viens, manager of North American sales and marketing. “We are talking about product characteristics, such as filling temperature, particulates, tendency of the product to splash or froth, etc.”

He explains that if a company is trying to dispense baby food into containers, Bosch would suggest servo-driven aseptic filling machines with full-metal pistons. This type of equipment helps address precision in filling a product that is highly viscous and particulate rich, but also avoids weight fluctuations or overfill issues.

For products that need special attention paid to minimizing microorganisms and ensuring food safety, such as juices, hot-fill technology for hygienic bottles will be needed. This was the case when Coca-Cola Canners in South Africa started bottling iced tea, sports drinks and juices with and without fruit chunks. The facility had two existing PET bottling lines, but due to the high-pulp content of the juice, a new line was needed.

The company employed KHS, a manufacturer of filling and packaging equipment, to install a hot-fill line. The content is heated to over 100°C and filled at a temperature of approximately 83°C. The line can fill up to 48,000 bottles per hour, sized between 0.3 and 1.5 liters. To avoid damaging the fruit chunks during the filling, the line was equipped with two precision volumetric fillers where the fruit pieces are first bottled with a small amount of juice before the second filler tops off the bottles with pure juice. This understanding of the filler’s impact on the final product is important, especially for sensitive liquids.

“Some yogurts tend to ‘shear’ when being forced through small openings,” says Jan Sundberg, applications development manager for JBT Corporation. “The filler needs to have gentle handling inside the filler bowl/hopper and also as the product flows through the valve. Larger porting and short, straight paths for the product flow are key to minimizing any damage.” For instance, features like extra elbows, pipes and pumps can change the viscosity of a product, so eliminating them for these applications could offer protection against damage.

“Products like creams or oily dressings can only be dosed with a specific dosing station, for example, positive valve,” says Viens. “Otherwise, the rotary movement in standard dosing stations could damage the product, or the pump design could separate the oil from the base product.”

When bottling a product like beer, which has a tendency to foam, gentle filling is paramount. Breweries want to limit the amount of oxygen picked up by the beer as much as possible during the filling process, but also want to maximize throughput. To help address these issues, Krones has equipped its Modulfill filler with a level probe that includes a swirl.

“The swirl gently guides the liquid to the bottle wall and in the bottle,” says Stefan Kraus, product manager for filling technology. “Additionally, the filling valve is equipped with two different filling speeds. The result is a gentle filling process with low turbulence and less foaming behavior.”

Product and container versatility

Because of the wide variety of products being packaged at plants, more processors are looking for fillers that can handle multiple concepts. Equipment providers understand this, but might not be able to deliver a panacea yet.

“In the world of food, the day of ‘one filler fits all’ still hasn’t arrived due to the wide range of product characteristics,” says Viens with Bosch, which acquired filling and sealing equipment manufacturer Osgood Industries, Inc. in 2015. When Bosch Osgood introduced its tank-style pump, part of the objective was to address this need for fillers to handle many different types of products. Thus, the tank-style pump can handle a range of products, from liquid juice to viscous vat-set yogurt. “With this solution, the pistons that are used to pump the product are located inside the hopper. An even distribution of product above each piston and tight tolerances offer the user excellent lane-to-lane repeatability and eliminate the need for dynamic O-rings on the piston head.”

“Customers are demanding that new filling equipment is more versatile and can handle a full range of varying products,” says Sundberg. As a result, the JBT Unifiller filler can handle products with a thin, watery consistency to thick, chunky products with high solid content and large particulates. “[It] is a unique volumetric piston filler with short product paths and larger porting.” Additionally, the fill nozzles are designed for specific applications and can be easily exchanged.

Krones filling machines are also designed with flexibility in mind, says Kraus. As an example, he cites some of the company’s filling equipment that can be adjusted automatically via the filling probe, which addresses improved automatization as well.

For most of its filling machines, Serac uses net weight filling technology, which controls the amount of product dispensed into the container to give an accurate measure of what is inside. Alan Bonanno, marketing manager for Serac, says because aeration, temperature and viscosity do not affect the accuracy of a net weight filler, it can handle a variety of products with different characteristics.

Product flexibility isn’t the only filling demand, but the shapes, sizes and materials used in different containers being filled are also highly variable. Knowing the type of container is important for packaging providers to understand, says Viens, as it “will drive the configuration on numerous machine stations and the number of lanes required.”

“Larger containers will require larger valves, longer filling cycles and increased pitch between valve centers; this all drives larger filler frames,” says Sundberg. However, it is not just the container size that is a factor, but material as well. “Glass is sometimes more difficult simply because it is that much heavier than cans. The back pressure on the infeed section is higher, and reinforcements might be needed. A traditional wedge-type container stop will not work with glass.” However, JBT uses a rotary-style container stop, which he says won’t break glass.

Many companies are moving to lighter weight packaging and using materials such as PET. Serac has adapted to this by developing the universal neck gripper, which moves the container by the neck through the machine. This can increase throughput and lower costs by reducing set-up time and maintenance needs.

“Because the neck diameter of most containers have standardized sizes, the Serac neck gripper can handle different size containers without changing tooling, thus saving tooling costs that are normally required for machines without neck grippers,” says Bonanno.

Krones filling machines allow a broad range of similar container types with varying volumes to be filled with one machine. When Ocean Spray opened its new production facility in Lehigh Valley, PA in 2014, the company installed a Krones flex PET line that can produce 11 different package sizes and operates at 350 bottles per minute at 87.5 percent efficiency. Different container types can sometimes be done on one machine, says Kraus, but glass and cans have to be kept separate.

Accuracy and efficiency

Having properly filled containers is one of the key elements to ensure product quality and control giveaway. Under-filled bottles, at best, can result in consumer complaints and, at worst, can land a company in court. However, overfilling can be costly and wasteful. This means a filler must be accurate and consistently maintain that accuracy over the years.

“Accuracy is a function of many different parts of the filler,” Sundberg says. In other words, the machine must be robust to fulfill the criteria most important for processors, which are uptime and maximizing operational throughput with minimal maintenance.

Because the filling accuracy depends on so many factors, such as technology used and varying product characteristics, one method to improve performance is increasing automation. Bosch’s Viens recommends using programmable logic controllers (PLCs) that control and consistently make adjustments to the filling parameters and product flow. Additionally, in facilities that use multilane fillers, he stresses the importance of eliminating lane-to-lane variations during the filling process. He recommends having sterile air pressure in the hopper to minimize variation of the fill and having “a level distribution of the product in the hopper above each piston.”

Serac’s Bonanno says the key to increasing accuracy during the filling operation is control of the flow rate. The Servo Dynavalve filler monitors and adjusts the flow rate via a servomotor controlling the opening and closing of the valve and a stepper mechanism to maintain a constant flow rate. Serac also designed its new FC Filler Capper’s filling station to integrate three components into one standardized action.

“Our new designs offer increased filling speeds by employing an advanced algorithm to monitor the filing cycle for greater accuracy and a new filling valve utilizing servo motors for increased efficiencies and precise filling,” he says. Additionally, this precision helps eliminate product waste by ensuring no overfilling or overflow of product. “This not only saves money by saving product, but it also reduces maintenance expenses associated with cleaning the machine and the area surrounding the machine.”

Conserving energy is becoming more of a sticking point for processors trying to save on utility costs as well as decrease their environmental footprint. Viens says Bosch works to improve this by installing electrical motors and servo drives, which reduces the need for operators to manually input different formulas, formats, quantities, etc.

“All major movements are also propelled by servo motors, enabling quick and easy adjustments to the set-up, enhancing overall equipment effectiveness [OEE] and offering speeds of up to 40 cycles per minute,” he says. “Stations for additional features, such as snap-on lids, can also be easily integrated using servo drives, further enhancing line flexibility.”

To address energy efficiency, Krones’ Modufill machines are also equipped with servo drives as well as a proportional flow regulator. This technology allows processors to electronically adjust the flow speed of the liquid in the filling valve without the need for pneumatic air.

Minimizing changeover time through hygienic design

With many processors increasing the variety of products to fill, minimizing cleaning and changeover time continues to be a major focus. Fillers with automatic clean-in-place (CIP) capabilities have long been identified as a way to speed up the cleaning process. However, Sundberg says this is only possible if the filler bowl and valves have a self-draining design, which traditional piston fillers did not have, but the JBT Unifiller does.

“Many folks don’t understand this,” he says. “An automatic quick product flush and hot water rinse is only possible if you can drain the product lines, bowl and valves completely without any disassembly.”

With Bosch-Osgood’s tank-style pump solution, the pistons and nozzle stems retract into the hopper during CIP. Viens says some of the company’s clients have reported decreased CIP times versus traditional horizontal piston fillers. Also, as previously noted, the design eliminates the need for dynamic O-rings, which can break and fall into a container.

Increasing the general sanitary design features of fillers continues to be another area of improvement. More equipment is incorporating sloped surfaces for increased drainage and avoiding usage of hollow bodies, which can facilitate product buildup.

“Making the filler easy to clean and visible for the operators makes it automatically a cleaner machine,” Sundberg says. Elements such as clear guarding and LED lighting can illuminate the dirty areas. “If it’s visible, it will get cleaned.”

Serac’s new FC Filler Capper was designed to reduce contamination via a sloped shroud and the elimination of a traditional holding tank, says Bonanno. He recommends looking for stainless steel usage on equipment, including airlines and standoffs, which helps keep the machine sanitary. Machines that use a properly designed laminar flow system as well as blow tubes and wash jets will also help reduce contamination.

These are all general clean equipment design principles that are good to keep in mind. However, the filler’s level of hygiene will be dictated by the specific needs of the filling product.

“It’s best to define the product’s shelf-life ambitions, flavor profile and other requirements,” says Tetra Pak’s Grainger. So, instead of beginning with the equipment choice and then developing a product, start with determining whether the product needs clean, ultraclean or aseptic filling technology.

“For food with a shelf-life expectancy of up to 14 days, like edible oils or hot-filled fruit juices, most manufacturers use the clean technology, which doesn’t require additional container decontamination,” says Viens. “Whereas, in case of products requiring up to six weeks of storage, the packaging materials are treated and disinfected, and the fill process is completed within the confines of a sterile air tunnel. The highest possible hygiene level, allowing for up to one-year shelf life outside of the cooling chain, is a solution chosen by infant and clinical food producers.”

Operator interaction

Even though filling machines are trending toward more automation, equipment must be easy for operators to use. More attention is being paid to designing intuitive human machine interface (HMI) with panels that are easier to use and read.

“A proper set-up of the HMI is vital,” says Sundberg. JBT has incorporated pictures on the HMI of some machines so operators can detect a problem with just a glance, also without needing to overcome any language barriers.

Some equipment providers have been focusing on configuring machines with one standard HMI system. For instance, Bosch is using touchscreens with features designed to make operators’ jobs easier, like including FAQ sections and using more graphical representations. Viens says this helps operators monitor performance more closely and prevent potential downtime.

“Another way to increase usability is to localize operator interactions to a specific zone,” says Tetra Pak’s Grainger. The company redesigned its filling machines to locate all modules on the ground level, thereby eliminating the need to climb stairs to execute commands on the second level. “This eliminates unnecessary movement and reduces the incidence of fall or other injuries.”

However, it might not just be improved machine-operator interaction that boosts worker efficiency. Grainger takes a more holistic approach and advises processors to embrace the 5S methodology. This is a workplace organizational method that uses a list of five Japanese words, which can be translated to: sort, set in order, shine, standardize and sustain. These concepts instruct employees to maintain an orderly environment through tidiness and mise-en-place work strategies. Also, through this scheme, the onus is put on managers to identify and employ best practices, which are designed to maintain high standards.

“A plant can have all the technology in the world, but they won’t get very far if the floor is a mess, and the workers don’t know what they’re supposed to do next,” says Grainger.

Sidebar: One-step bottle forming and filling

Traditionally, blow molding and filling were two separate manufacturing steps, using compressed air to form plastic containers. Recently developed LiquiForm technology combines these processes into one by using pressurized liquid to form a rigid plastic container.

“LiquiForm represents a significant opportunity for the consumer products industry by creating a step change in efficiency and flexibility,” says Ann O’Hara, president of LiquiForm Group, a joint venture between Amcor and Sidel.

The preform is placed in the mold, and the actual liquid to be bottled is then forced at high pressure into the preform, molding it into the bottle shape, thus, resulting in a filled bottle. The benefits include energy reduction due to the elimination of compressed air in the process; cost efficiency since there is no redundant equipment needed for traditional blow and fill operations; and saving space due to the combined processes.

The LiquiForm technology has been validated with a range of packaging substrates, products and conditions using the same LiquiForm machine for cold, ambient and hot-fill containers. Recently, the LiquiForm Group and Krones have entered into a technology licensing agreement to further develop and commercialize this technology.

“With the LiquiForm technology, Krones has an opportunity to build on existing bottling technology, intellectual property and know-how to develop unique industrial solutions for improving the total cost of ownership for our customers even further,” says Dr. Christian Compera, head of bottling technology at Krones.