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Edible Oil , Technology


PET bottle filling machine: rotary, isobaric and gravity


Technological innovation has led to the development of increasingly evolved liquid filling machines, offering a progressively better performance.

All the monoblocks are designed to ensure great operating flexibility, high levels of efficiency and a drastic decrease in format change over times.

A lot of attention was also paid to the sanitizability of all the component involved in the filling process.


In this article we will see in detail some of the most efficient types both in terms of precision and production speed.

We will talk about:


  • Rotary volumetric electronic fillers for large sized PET containers for still products
  • Isobaric mechanical filling monoblock for carbonated products
  • Gravity mechanical filling monoblock for hot or cold non-carbonated products

READ ALSO: "PET bottle filling machine, filling techniques: electronic, volumetric & gravity volumetric"


PET bottle filling machine:
rotary volumetric electronic fillers

 pet bottle filling machine


Large sized PET containers for still products

When a PET filler is required to handle and fill large sizes containers (for example from 3 to 20 litres) then it is necessary to consider a specific version of the rotary volumetric electronic filler for still products.


It is an electronic valve with no contact volumetric filler managed via a magnetic flow meter to define the bottle’s content and a 3-positions diaphragm valve with flow partialization.


The nozzle with wide pass-through sections, specific for large sizes bottles, is designed to obtain the maximum flow through the inlet of the bottle, minimising the turbulence of the product, in particular in the end of filling phase to prevent product leak (“splash out”).


During filling, the bottle is kept in position using mechanical gripper. Inside the monoblock, the full bottles over 5 lt are handled from the bottom. Operating management is very simple, with the selection of the various formats directly from the operator control panel.


This type of machine has many advantages:


  • Extremely clean filling: no contact between the valve and the bottle.
  • High filling speed.
  • High content precision.
  • The air in the bottle does not come into contact with the product feeding circuit


There are also models with mass flow meters, ideal for viscous or low conductivity products, such as edible oil, deminaralised water.



PET bottle filling machine:
sobaric mechanical filling monoblock for carbonated products


pet bottle filling machine

The bottling process takes place via isobaric filling, with the container touching the valve, then creating an overpressure in the bottle that is able to equalize the pressure in the tank.

In this way, it is possible to fill liquids with a high CO2 content without releasing it during the filling phase.

In addition, the depressurisation phase is carefully managed, avoiding the formation and leakage of liquids, before releasing the bottle at the end of the filling process.

These machines feature a central tank and a valve with height adjustable moving filling tube to define the level in the bottle, easy to sanitise.

The neck-handling PET bottle transfer - does not require for monoblock height adjustment.


This solution ensures a host of advantages:

  • Product deflection without deflector (swirling device), to minimise foam during the filling process.
  • A single vent tube for every format
  • Automatically engaged dummy bottles.
  • Manifolded decompression carried out with the filling tube raised.
  • Quick changeover for different necks and bottles diameters.


Also the performance is impressive: fillers with 20 to 160 valves boast a speed ranging from 3,900 to 33,000 b/hour on 1.5 l with carbonated drinks (at 13°C). 



PET bottle filling machine:
ravity mechanical filling monoblock

  pet bottle filling machine

Hot or cold non-carbonated products

In these case we are referring to PET filling machines, which are ideal for hot or cold non-carbonated products.

They have a central tank, with product feeding form the bottom of the rotating manifold, a stainless steel draining base, a simple and easy to sanitise valve, with notably reduced format change over times.


The advantages of this type of fillers include:

  • Centralised level adjustment, via a single intervention point.
  • Universal product deflection without deflector (swirl device).
  • No dynamic gaskets in contact with the product: the shutter is sealed by a simple membrane, protecting the movement form contamination.
  • Simple to operate. 
  • Evacuation to the outside of air returning from the bottles to prevent possible contamination.
  • Optional automatic dummy bottles
  • Valves made of AISI 316 stainless steel.
  • Quick format change over for necks with different diameters.

 pet packaging for impulse shopping


Written by SIPA

With 30 years of experience in PET containers solutions, SIPA has acquired considerable expertise in all available bottle manufacturing and filling technologies, from preforms to finished products, for the food and beverage, chemical products, cosmetics, detergents and pharmaceutical sectors.