New KHS filler series for cans

Ludwig Clüsserath*

With the electronically controlled, volumetric Innofill Can DVD filler KHS is launching a new series of canners to market. Like the generation of Innofill Glass fillers introduced about two years ago and now extremely well established, the Innofill Can DVD is distinguished by its optimum hygienic design. Its excellent filling quality goes hand in hand with a further improved line availability, this brought about by shorter cleaning cycles and longer maintenance intervals. The system also profits from minimized water, energy, and sanitizing costs. Another huge plus of the Innofill Can DVD is the newly designed inert gas purging process (CAN+) performed prior to filling. This not only cuts the amount of CO2 used but also greatly reduces the residual oxygen content in the can. Other outstanding advantages of the new development include the hygienically improved centering bell for can sealing and the use of flavor-resistant materials in the filling valves. All told, the Innofill Can DVD heralds the dawn of a new generation of can fillers which is based on tried-and-tested practices and has also been greatly optimized wherever possible. 

For many different beverages at a rate of up to 120,000 cans per hour

Whether it's beer, mixed beer beverages, soft drinks, water, wine sparkling wine, or even health drinks you want to fill, the Innofill Can DVD can do them all! The new machinery can also hot fill as an option, which is so essential for the canning of juices, teas, and coffee beverages. If required, the system can be equipped with a pressure-controlled pre-snifter for very foamy beverages. The Innofill Can DVD has a maximum output of 120,000 cans per hour and processes containers holding from 0.1 to 1 liters.

No front table

As on the recently launched glass filler the Innofill Can DVD generation of filling machines has been designed without a front table. The conveyor and feed screw, transfer starwheel, filler carousel, and seamer are driven here by separate servo motors which are encased in stainless steel in the hygiene area or located in protective star columns outside the hygiene area.

* Development Manager, Filling and Process Equipment, KHS GmbH, Bad 

   Kreuznach, Germany, Phone: +49 671 852 2501

The height of the cam race that lifts the can centering bells is adjusted by stainless steel linear drives which are well protected by VA columns. This does away with the need for any gears, couplings, or joint shafts. There are also no more open gear wheels or screw fittings in the hygiene zone, in turn also cutting costs for servicing, maintenance, and energy. On the Innofill Can DVD the star columns and bearing elements for the feed screw and infeed belt are directly connected to one another and to the filler carousel by cross pipes with no flanges. They are secured by hygienic sealing systems on the exterior, and cables and lines are laid in the connecting pipes. If required the filler carousel support structure can be fabricated in stainless steel, making it resistant to the foam cleaners commonly used in the industry – like all the other materials that go into the makeup of the new Innofill Can DVD.

Consistent implementation of hygienic design

The consistent implementation of hygienic design starts straight off with the conveying of the cans to the filler. A feed conveyor open on both sides provides optimum conditions for cleaning and disinfection. The conveyor with a transfer chain to the can seamer is also available in an open hygienic design and thus equally easily accessible for sanitizing and disinfection. An optional automatic sanitizing system can be integrated into the transfer chain with the spray nozzles directed at all critical points. A screw spaces the cans before they enter the infeed star. On the Innofill Can DVD format parts such as the aforementioned screw and star enable a quick runoff of liquids. They are also low in weight, allowing them to be changed quickly and easily without the need for any tools. 

Tubular ring bowl saves energy, water, and cleaning agents

The tubular ring bowl built into the Innofill Can DVD is not only hygienically designed but also helps to save energy, water, and cleaning agents. Its shape keeps the CIP and SIP process very simple and utilizes little media. The tubular ring bowl is also lighter than the classic square ring bowl, therefore reducing heating and cooling times. Less drive force is also needed, which in turn has a positive effect on the machine's energy consumption. 

Filling valves easy to fit and remove

Another great advantage of the Innofill Can DVD is that each filling valve can be fitted to or removed from the valve support by simply tightening or loosening three cap nuts.  This compact valve unit includes all control cylinders, the can bell with its lifting rod, and the bell lowering device. When the filling valves are fitted, all pneumatic connections and the connections for the beverage and process gases are automatically made – and automatically released when the valves are removed. This means that there is no hosing or cabling in the hygiene area. The solenoid valves needed to drive the filling process are encapsulated outside the hygiene and filling area in the filler carousel, making them hygienically safe. 

Media feed through hygienically designed pantograph joints

When changing the machinery over to a new can size, the height of the filler turret must be adjusted. In order to ensure a safe and hygienic feed of media from the rigid supply pipes to the height-adjustable rotary leadthrough, on the Innofill Can DVD connecting pipes in the form of pantograph joints with aseptic sealing systems are used. A new rotary leadthrough enables an extremely safe transfer of media. The seals operate without any grease lubrication, with the bearings safely lubricated away from the hygienically sensitive media area. Even if the bearings are overlubricated, food-grade grease still cannot enter the beverage and process gas seals.

Compact valve manifold saves up to 50% space

The canner has a compact valve manifold which saves around 50% of the space needed to install the valve manifold used to date. Less space is needed because the fittings are constructed vertically instead of horizontally. Another plus point of the compact valve manifold is that it is extremely easy to service, as the new alignment of the individual components makes them much easier to access. The compact valve manifold is positioned next door to the filler cladding so that media has only a very short distance to travel to the filler carousel. 

Top-level flavor resistance 

All sealing areas on the Innofill Can DVD's filling valves are fitted with flavor-resistant seals, membranes, and expansion joints. Resistance to flavors is a given thanks to the utilization of PTFE materials or special elastomers. Flavor carryover when the product is changed over following a system clean is reduced to a minimum; the filler can therefore be switched over from coke to still mineral water or from energy drink to shandy without any risk to the product flavor. 

Pneumatic air hermetically sealed

So that the purging, pressurization, and snifting processes upstream or downstream of the filling system can be controlled as required, Innofill Can DVD technology includes integrated pneumatic actuator plungers. The sliding sealing collars used to date have been replaced by gas-proof expansion joints, meaning that pneumatic air is hermetically sealed from the outside area. Leaked air can therefore no longer escape into the hygiene zone. 

Centering bell guided by an expansion joint

Can fillers have a special centering bell which is lowered onto the can prior to purging, pressurization, and filling in order to seal it. The standard practice to date was to guide the bell using a sliding seal which shifted between the sterile and unsterile areas of the machine. This design poses a hygienic risk which calls for very careful hygienic management. It also requires water lubrication across the open can with the result that the filling valve is covered with a film of water above the open can mouth. There is a particular risk of contamination when cans are not pasteurized following the filling and seaming process. Grit can also enter the can. One important new development on the Innofill Can DVD in this respect is to have an expansion joint guide the centering bell – which is an absolute first. This joint seals the can mouth under aseptic conditions, doesn't require any lubrication, and is hygienically safe on all counts. It can also be incorporated into the CIP sanitizing and sterilizing process which wasn't feasible on the former setup. The centering bell with a sliding seal could only undergo limited cleaning on the outside.   

Innovative CAN+ purging process for a minimized residual oxygen content in the can and targeted CO2 savings

The force with which the bell seal is pressed against the can mouth can be pneumatically adjusted by the expansion joint so that it always perfectly suits the size and stability of the can. Once the can mouth has been completely sealed the next step is the CAN+ inert gas purging process to remove any residual oxygen from the can. Up until now it was usual for pure CO2 to be fed from the ring bowl gas chamber through the pressurization channel into the can at a purge pressure equivalent to the pressurization pressure which for beer is between two and three bar, for example. After purging the gas either passes through a purge gas channel in the direction of the valve manifold and from there into the atmosphere, or is extracted from the production shop by a special discharge system. The resulting high purge pressure in the can leads to the current high consumption of CO2 which when purging cans to be filled with beer, for instance, is between 500 and 1,000 grams per hectoliter. 

The new CAN+ purging process designed for the Innofill Can DVD specifically throttles the gas feed, thus resulting in a purge pressure that is close to atmospheric pressure. This both lowers the gas density in the can and the consumption of CO2 –and/or leads to a comparably significant reduction in the amount of residual oxygen contained in the can.  Laboratory results have shown that the residual oxygen content after pressurization using the new process is reduced by up to 50% for a 0.5-liter can, for example, and the CO2 consumption cut by up to 20%. If we take today's usual values for oxygen pickup, even less CO2 is required.  As is common practice CO2 enters the can from a separate channel which is connected to the gas chamber of the tubular ring bowl where a pure CO2 atmosphere constantly prevails. To keep as near to atmospheric pressure as possible during the entire purging process the flow of gas is limited by a defined flow cross-section, this action performed by a restrictor unit integrated into the valve seat. This can be automatically controlled by the motion of the liquid valve without the need for an additional switching function. This means that neither a separate valve nor another solenoid valve or electronics output are required. The new, beneficial purging process can therefore be implemented without the complexity in the filling valve being increased. To prevent a back pressure from building up when the CO2 is discharged during purging, the filling valve has large cross-sections. The holes which discharge the return gas flow are evenly distributed across the can diameter. Purge gas is removed from the system through the purge gas channel – as is usual – yet here two separate gas valves are used. 

Electromagnetic inductive flow metering for maximum filling accuracy 

Even during the pressurization process the restrictor unit is exactly matched to the system requirements. This restriction is lifted for the filling process. The can is at the same pressure as the tubular ring bowl, with the optimum rate of flow of the product to be filled stipulated by the level in the tubular ring bowl. 

Maximum filling accuracy is provided by the Innofill Can DVD's use of electromagnetic, inductive flowmetering. Product savings are therefore virtually a given. It no longer matters whether the cans supplied by different manufacturers are the same or not; if a filling quantity of 0.5 liters is programmed, then the can filled by the Innofill Can DVD will contain 0.5 liters of beverage. In contrast, users of conventional fill level systems have to take possible tolerances in the supplied cans into account when selecting fill levels, with overfilling not unusual here. Another outstanding advantage is that no mechanical parts come in contact with the product being filled during volumetric flow metering.   Aseptic sealing systems and membranes are present in all beverage and gas passages. Once filling has finished, snifting begins. The existing pressure is reduced to that of the surrounding atmosphere and gas is discharged through a separate final snifting channel. Pressure-controlled snifting with little foaming is also a possible option.                                                                     

Minimum changeover times

The Innofill Can DVD can be changed over to a different filling valve or new product and adapted to new can heights or different can diameters at the press of a button (can mouths from 200 to 206 mm can be processed without the bell having to be changed). Changeover times for can guide parts have also been kept as short as possible. The machine operator simply calls up preprogrammed settings and continues production with the new product or type of can. 

Twin valve control for even more simplicity

Twin filling valve control is standard on the Innofill Can DVD. This means that two filling stations have been combined to form one technical unit, considerably reducing the control complexity of the machine. If, by way of example, we take a can filler with 164 filling stations, three solenoid valves and three electronic outputs are normally needed per filling station to control the gas processes, with all the hosing and cabling these require. This means that we have a total of 492 solenoid valves and the same number of electronic outputs with all the necessary connections in use. Twin valve control reduces this number to 246 apiece. This not only makes the equipment less complex and cuts down on the number of parts; other benefits include lower servicing and maintenance costs – without detriment to the quality of the filling results.

Option: fully automatic CIP plate solution

If CIP is to be performed on the new generation of can fillers, what are known as rinsing plates are responsible for sealing the filling valves. The filling system can also be fitted with automatic CIP plates if such an option is required. When a customer opts for the fully automatic CIP plate solution, here integrated spray nozzles ensure targeted exterior cleaning of the filling valves and CIP plates.  All product and process gas passages can be reliably cleaned using CIP sanitizing; even the hygienically critical inside of the centering bells is fully included in the cleaning process. CIP sanitizing is also possible when the filler is stopped. Smooth surfaces, few parts, and easy access – the result of consistent hygienic design – help the exterior cleaning of the Innofill Can DVD. 

Minimum installation and commissioning times

The much lower complexity of the Innofill Can DVD compared to previous machinery shortens installation and commissioning times, among other things. Another advantage KHS customers who already use the Innofill Glass platform profit from is that there are many parallels thanks to the consistent hygienic design of both filler series, meaning that operators can familiarize themselves with the new system extremely quickly. Many areas also utilize the same spare and wear parts, with the result that warehouse inventories are reduced and therefore costs saved.

Transparent outer cladding for excellent interior views

On the Innofill Can DVD and its monoblocked seamer the external cladding is made of glass or Makrolon panels which give operators an excellent view of the filling process and enable them to permanently monitor the hygiene situation. In addition, great value has been attached to providing ample access to the relevant components for cleaning and maintenance. If required, part of the cladding ceiling can be fitted with filter units which clean the shop air directly. A slight amount of overpressure ensures a permanent flow of air from the ceiling to the floor, providing the open can conveyors with a continuous supply of freshly cleaned air and specifically preventing the entry of unfiltered shop air. 

Innovative operating system leaves nothing to be desired

The operating system included in the new Innofill Can DVD series of fillers is the KHS Human Machine Interface. The result is user-friendly machine operator prompting that employs buttons, colored graphics, easy-to-remember icons, and interactive handling instructions, all of which have been kept simple and are self-explanatory. The system is subdivided into several levels, thus providing access to varying degrees of viewing detail and different operating levels as the specific application requires. The new interface also allows user profiles to be accessed with an ID card, displaying relevant data to specific individual users. 

Full package of benefits

To sum up, the new Innofill Can DVD series of fillers gives the brewing and beverage industries a full package of convincing benefits. On the one hand these are the result of a consistent hygienic design; can centering bells without water lubrication have been realized for flawless hygiene for the very first time.  On the other, considerable improvements have been made to the filling technology. The significant reduction in the amount of residual oxygen in the can, coupled with a clear saving in CO2, will surely be of great importance to companies who want top filling quality. Another important factor is that flavor carryover has almost been eliminated when filling different products on the Innofill Can DVD. What's more, thanks to twin valve control – and to the many other improvements in the hygienic design, many of which result in energy and water savings – operating costs and servicing and maintenance measures have been reduced.