Packaging Systems - Filling Machinery
Loaded on to the conveyor and, if necessary, cleaned, bottles are now ready for the product! Machinery used to fill bottles on automatic packaging systems will use various principles to move product in to the containers based on factors such as speed, viscosity, container sizes, the presence of particulates and more. The different types of filling principles are described briefly below.
OVERFLOW FILLING MACHINE
The overflow filling machine differs from other liquid fillers in that it will fill bottles to a certain level each cycle, every cycle. So even where bottles differ slightly in interior volume, the overflow filler will each bottle to the same level. This is achieved using a nozzle that creates a seal over the bottle opening, then allows product to "overflow" into a return port in the nozzles when it reaches the desired level.
GRAVITY FILLING MACHINE
The gravity filler uses a volumetric filling principle which will open and close valves to release product. By timing the opening and closing of the valves (which can be done individually for each head), the filler produces an accurate volume with each cycle. However, relying on gravity for the fill, this machine will typically only be used for thin, free-flowing products. Unlike the overflow filler, which uses some variation of the same nozzle, fill heads and nozzles can vary to accommodate different containers and products with a gravity filler.
PUMP FILLING MACHINE
It might be simple to guess that a pump filling machine will use some type of pump to move product through the plumbing and in to the waiting containers. The type of pump being used will depend on the specific product or products being filled as well as some other factors. Pump fillers also provide a volumetric fill based on time or, in some cases, some movement of a component of the pump (for example, a half turn of a gear on a gear pump). Similar to gravity filling machines, pump fillers can use a variety of different fill heads and nozzles based on the product and project. However, pump filling machines are better suited to handle thick or high viscosity product as the flow is enhanced by the pump itself.
PISTON FILLING MACHINE
Piston fillers, like pump filling machines, are most often used for higher viscosity products. The piston itself retracts with each cycle to allow product to enter the cylinder. As the piston returns to the cylinder, the product is moved out of the machine and in to waiting containers. Because the volume of the cylinder never changes, the piston filler also provides a highly accurate volumetric fill. The wide open space of the piston filler also allows for products with large particulates, such as jams and jellies that include fruit pieces or sauces with vegetable pieces. Nozzles will vary to accommodate the product with a piston filler as well.
NET WEIGHT FILLING MACHINES
Also with a descriptive name, the net weight filler provides an option to both the volumetric fills and the fill to level system described above. Net weight filling machines will use scales on the power conveyor system and under the fill heads. These fillers use a set weight to turn off the flow of product, and will usually include a tare for the weight of the bottle or other container. The nozzles for net weight fillers will also vary according to the product and project at hand.
Automatic filling machines will use an indexing system, such as pins, a starwheel, a screw or other system, to automatically position bottles under the fill heads. Almost every automatic filler will include an easy to use, touchscreen operator interface. However, all of the principles described above can also be used for semi-automatic filling machines, which simply require a little more operator interface. To learn more about some of the different filling machines manufactured at Liquid Packaging Solutions, Inc., visit the Filling Machinery section of our website or call to speak with a Filler Specialist today.