The three in one isobaric filling equipment is an efficient device widely used in liquid packaging such as beverages and beer. Its core principle is isobaric filling (i.e. maintaining pressure balance between the container and the storage tank during the filling process). The following is a detailed explanation of its working principle and key features:
1. Basic components
Three in one equipment usually integrates three major functions: flushing, filling, and sealing, including:
Rinse unit: Rinse empty bottles with sterile water or disinfectant.
Filling unit: Complete liquid filling under isobaric conditions.
Sealing unit: Immediately seal the filled container (such as screwing, capping, etc.).
2. Principle of isobaric filling
The core of the filling process is to prevent the liquid from producing foam or spraying due to pressure difference. The specific steps are as follows:
(1) Inflate and pressurize
Empty bottles enter below the filling valve through the conveying system, and the filling valve seals the bottle mouth.
Inject inert gas (such as CO ₂) or compressed air into the bottle to make the pressure inside the bottle equal to the pressure of the reservoir (usually 0.2~0.4MPa).
(2) Liquid filling
When the pressure inside the bottle is balanced with the storage tank, the liquid flows steadily into the bottle through the filling valve under the action of gravity or slight pressure, avoiding turbulence or oxidation.
The liquid level is ensured for accuracy through quantitative control, such as liquid level sensors, time control, or volume measurement.
(3) Pressure release
After the filling is completed, the filling valve slowly releases the residual gas inside the bottle to prevent the liquid from suddenly depressurizing and splashing.
The filling valve is lifted and the bottle enters the sealing station.