Following the Fluid Through the Liquid Filling Machine

Following the Fluid Through the Liquid Filling Machine

The goal of any liquid filler is to get the product to the waiting bottles or other containers, but the product will not always travel the same path.  Below we look at a few of the more popular filling machines and follow the typical path of the product to the containers, assuming that each begins with the product in a bulk tank or other supply container.


Upon leaving the bulk tank, the fluid in an overflow filler moves into a resupply or reserve tank (sometimes also called a recirculation tank).  A pump will then move product into a manifold that will deliver the fluid to tubing leading to each of separate fill heads on the machine.  The overflow nozzles deliver the product to the bottles, but unique to this liquid filler, not all product will stay in the bottles.  Instead, once the product reaches a certain level, the liquid will overflow through the nozzle return port and back into the resupply tank, to begin the process again.


Gravity fillers differ slightly from overflow fillers in that product from the bulk tank will be delivered to a supply tank, normally located above the fill heads.  From the supply tank, product will move into a manifold and reach the fill nozzles through tubing, similar to the overflow filler.  However, as the name suggests, this packaging machine uses gravity to move the product down to the fill heads and through the nozzles to bottles or containers.  No pump is used (except possible to deliver from the bulk tank to the supply tank) and recirculation does not occur.  Instead, ball valves will be used to start and stop the supply of fluid.


Though pumps exist on overflow filling machines, a pump filler differs in that each fill head will use a pump to deliver product.  So after leaving the bulk tank, the product will move through the supply tank to the individual pumps, one for each fill head.  Fill nozzles, which can take a variety of forms, then deliver the product to the waiting bottles.  The fact that each fill head uses its own pump removes the need for a manifold to deliver product.


Piston fillers work similar to the pump fillers, moving through a three way valve after leaving the holding tank.  From the three way valve, product will enter the piston as it retracts, and will then be pushed out of the piston and through the fill nozzles when the piston re-enters the cylinder.  Both pump and piston fillers are popular machinery for more viscous liquids, with assistance coming from the pump or piston in pushing product through the pathway. 
These are, of course, general configurations, and even the filling machines described above may be designed to move product along a slightly different path to reach the bottles.  Other packaging principles can also be used, such as net weight fillers and siphon filling machines.  For assistance in choosing the correct filling machine for your own packaging project, consult with one of the Packaging Specialists at Liquid Packaging Solutions.