Aerosol Filling Process

An aerosol is made up of several basic components:

  • An aerosol can
  • The product
  • The propellant
  • A valve
  • An actuator
  • A dust cap

Here at Aztec Aerosols, these all have to be assembled, and this is achieved using automatic filling machinery.

For conventional aerosols the key steps in the filling process are:

1. Our process starts with an empty container which is either made from tinplate or aluminium.

2. The empty containers travel along the production line and the bespoke product, in the form of a liquid, is added to the can. This contains all of the active ingredients included by our Research and Development team, except for the propellant. The volume of liquid is very carefully controlled to ensure that it conforms t Weights & Measures legislation.

3. Our machinery then fits the Aerosol valve to the can. This is a very critical operation and the crimping machinery has to be carefully set up by our technical staff to ensure that the can/valve seal does not leak.

4. From there, the cans continue along the production line and the machinery injects the propellant, under pressure, through the valve. The propellant may be in the form of a liquified gas, or a compressed gas. If a liquified gas is used it will exist as both a liquid in the liquid phase and vapour in the aerosol can head space. If a compressed gas is used, it will usually only be in the head space, above the liquid in the can, and there will be little or no increase in liquid volume. Again, the volume of propellant is very carefully controlled to ensure that it conforms to Weights & Measures legislation. The aerosol is now in a pressurised state due to the addition of the propellant.

5. Once filled, the cans are tested for leaks.

6. Once tested for leaks the weight of the can is checked to ensure the correct fill.

7. The actuator is then fitted and the cans are date and batch coded, to ensure full traceability, before the cap is applied.

8. If labelling is required the cans will pass through a labelling machine applying either wet glue or self adhesive labels.

9. The product and either be boxed or shrink wrapped.