This method involves the use of special washing nozzles inside the container. Depending on the type of washing, these may be:
- Static washing nozzle, which delivers cleaning solution or pressurised water in specific directions.
- Rotary wash nozzle, which rotates when the cleaning solution is delivered, providing a more effective mechanical action.
- Directional nozzles, which also rotate and are able to deliver a larger volume of cleaning fluid, providing a more intense mechanical action on the vessel walls.