Foaming liquid filling: a mastered challenge
Depending on the shapes of the packaging, the constraints of the product and the industry from which it comes, filling a foaming product onto a dispenser can be a delicate operation. Indeed, when the machine performs the dosage, if it is not adapted, the foam will overflow the packaging and in the best case, soil the bottle. We talk about the cleanliness of the dosage when we manage: the problems of foam, the drops at the end of the dosage and the absence of filaments.
Plunge cane spouts
Historically, the first solution found to avoid foam was to fill bottles from the bottom. The spout enters the packaging, then comes out as it is filled. This method solves foaming problems in most cases. However, plunge rod spouts have many drawbacks.
The first is a drop in rates: the nozzle must dive before the start of dosing then come out at the end of dosing. The second drawback is the duration of the adjustment times. Indeed, when changing packaging format, the operator must again adjust the high position of the spout, the low position, the speeds of the up-and-down movement and the flow rate of the spout. In addition, depending on the characteristics of the liquid, the spout may drip at the end of dosing. Finally, plunge rod spouts involve risks of cross-contamination (or cross-contamination). If the packaging in which the spout is immersed is soiled, the spout will in turn be soiled, which will cause contamination of the entire batch. As this risk is not acceptable in the pharmaceutical and food industries, manufacturers have had to find new strategies for foaming liquid filling.
The evolution of grilled mouthpieces
A grilled spout
The next step was the use of grids in the mouthpieces. In fact, to reduce foaming phenomena, it is sought to transform a turbulent flow into a laminar flow. This is the role of the grids! In addition, the grids retain the drops by capillarity. This eliminates the risk of soiling the bottle at the end of the dosage. If these mouthpieces prove their effectiveness in 75% of cases, they also show their limits. For the most foaming products, classic grid spouts are not enough. Some manufacturers then refer to plunger rod spouts. However, there is a new technology!
Warning: the spout grids should not be used for all liquids. When used with viscous products, the grids create filaments which soil the bottles and slow down the dosage. If you want to filter your products for quality reasons, ask the manufacturers to add a filter system. The filters are specially designed for filtering, the grids to manage the filling of foaming liquid .
The result: nozzles
A plug & play nozzle
Result of research on the filling of foaming liquid, nozzles with nozzles have made it possible to solve the various problems. These beaks contain 1 major evolution: the nozzle. This constriction makes it possible to maximize the action of the grids to obtain a diffuse and laminar flow. The advantages of nozzle spouts are multiple.
First of all, the most foaming products are perfectly controlled by the nozzles. Also, having no need to dive, they are much less expensive than plunge rod spouts. Easily removable and cleanable, they are generally simply screwed in place of another spout. Finally, they retain the advantages of grid spouts: elimination of the risk of cross-contamination by intrusion of the spout into the packaging and of drops at the end of dosing by the capillary effect of the spout on the liquid.
Conclusion
For foaming products, the most suitable solution is the use of a nozzle. However, there is no one mouthpiece that responds to all liquids. For example, for filling viscous products, other types of more suitable nozzles exist. In any case, ask the manufacturer to show you tests with your products. You will be able to judge the cleanliness of the dosage. But also the simplicity and robustness of the equipment, its precision and its cleanability.
For your foaming products, we equip all our liquid dosing machines with nozzles. Ask us to carry out filling tests on your products in your packaging!
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