The Kugler Flexofill machine fills neutralising liquids into cartridges. The cartridges are used in laboratory machines between the diagnostic screening processes. They rinse, remove, and calibrate possible residues from previous applications and ensure safe and unadulterated subsequent analyses.

Output and performance have not been the top priorities of this machine solution by Optima Group Pharma. Instead, the time factor has been essential for implementing the project. The diagnostics manufacturer considered the time-to-market as the decisive criterion of success for this neutralisation product. The project manager praised the constructive co-operation and reports that a “gang of four” fervently worked hand in hand to complete the project – the laboratory machine manufacturer, the packaging material company and the filling and packaging machine manufacturer as well as the client itself. This parallel engineering demanded increased communication efforts, which, however, was compensated by a much faster market launch.

The project manager is convinced that a project time of nine months is a good achievement. After all, unsteady containers and a few other special solutions involved a lot of additional ‘homework’ for the project engineers. The cartridges have a pyramid-shaped back-end to enable complete residue evacuation and are processed in four different formats from 8ml – 160ml. Filling quantities range from 4ml – 150ml. A welded aluminum foil guarantees safe sealing. The design of Kugler’s Flexofill was customised in all respects to meet the client’s specific requirements.

An all-round compact concept

The Kugler Flexofill is a monoblock machine; all the filling and closing functionalities are installed on one machine frame. In addition, Kugler’s engineers integrated a 20-digit buffer cylinder into the monoblock zone – a convenient space-saving solution for the customer in its assembly facilities. The buffer cylinder itself has 20 container racks, which can be attached vertically by snap-lock closures. Cartridges are loaded from the outside.

The containers are then destacked into the transport star wheel of the Kugler machine. At this destacking unit, the first station at the rotating cylinder is a vacuum ripper, which pulls off one cartridge from the cylinder guide and places it into a gap, especially designed for this purpose. Following this, the two-digit, servo-controlled dosing system with rotary piston pumps fills the desired liquid quantity. Filling of larger formats is realised by two steps at two stations; smaller volumes are filled at one filling position. To prevent foaming, a servo control keeps the movement of the dosing system’s filling needles precisely to filling level.

The next station is the sealing unit. The primary condition for accurate welding and tightly sealed cartridges are uncontaminated rims that are free of any liquid residues. This is ensured not only by needle movements coordinated with the filling level, but also by the servo-controlled rotary movement of the transport star wheel. The transport star wheel conveys the containers from one station to the next, and defined acceleration and deceleration movements keep the liquids inside the containers. The compact sealing station incorporates the functions of the foil uncoiling, cutting, pre-sealing and final welding units. The foil uncoiling unit feeds the foil to the welding unit, while the inner side of the foil is simultaneously sterilised by UV radiation. The cutting unit cuts the foil precisely to format size. None of the steps generates foil residues.

A manipulator accurately places the precision-cut foil onto the cartridge, where it is immediately presealed at the corners. Then, the cylinder advances the cartridges to the welding station for the final weld. After passing the optical control and the product reject, the cartridges leave the cylinder, for example the machine’s monoblock section. A special, two-component belt-type conveyor with a longitudinal groove ensures safe alignment of the cartridges which pass an inkjet printer in continuous movement. The OCR character recognition system reads and controls the imprint. The last station of this Kugler line is a belt checkweigher, over which the cartridges are moved in a horizontal position. On their way to the secondary packaging, the cartridges once again pass a product reject station eliminating products with incorrect print or weight.

The benefits of monoblock design

Fluent passage within the machine is the universal benefit of any monoblock design – there are no interface issues. For processing unsteady formats in particular, this has a positive effect on machine reliability. The line is operated under integrated laminar flow, ensuring that sterility of the cartridges meets pharmaceutical standards until final welding. The entire line meets FDA cGMP standards. Only certified materials have been used during production of the machine.

Format changeover takes 20min at most, as only racks and welding jaws for pre-sealing and final welding have to be exchanged. For the smallest size, a special filling nozzle and the star have to be fitted. Once a foil roll is empty, the splice station with the colour markings and a prolonged foil feed operates semi-automatically to support fast changeover. The line fills up to 30 containers per minute, and guaranteed filling precision is within standard range.