Gravity & Overflow Liquid Filling Machine

Description & Operating Principle

HMEC’s Gravity & Overflow Liquid Filling Machines utilize specialized coaxial filling nozzles to achieve a consistent cosmetic liquid level inside every container, regardless of minor manufacturing inconsistencies in bottle wall thickness or internal volume.

During operation, the nozzle seals against the bottle neck and liquid flows into the container under gentle gravity or low-pressure pump feed. Once the liquid reaches the precise height of the nozzle's vacuum return port, excess liquid and displaced air are seamlessly recirculated through a closed overflow return line back to the main supply tank—preventing overflows and ensuring an identical liquid level across all retail shelf displays.

Target Products & Applications

Gravity and overflow level fillers are ideal for free-flowing, low-viscosity liquids packed in transparent containers:

🍾 Spirits, Wines & Liquors

Whiskey, vodka, gin, wine, rum, and craft spirits in premium glass bottles requiring identical shelf-level alignment.

🥤 Water, Juices & Non-Carbonated Drinks

Packaged mineral water, clear fruit juices, flavored water, energy drinks, and iced teas.

🧴 Perfumes & Personal Care

Perfume colognes, body mists, aftershaves, astringents, mouthwashes, and cosmetic toners.

🧼 Household & General Chemicals

Glass cleaners, window sprays, clear vinegar, light disinfectants, and non-viscous chemical solutions.

Pros & Cons Comparison

✅ Advantages (Pros)

Uniform Cosmetic Fill Height: Guarantees identical fill levels on retail shelves even with glass bottle tolerances.
Cost-Effective & Reliable: Simple, robust mechanical design with low initial cost and minimal maintenance.
Continuous Closed-Loop Recirculation: Excess fluid return prevents spillage, splashing, and product loss.
High-Speed Multi-Head Capability: Fills up to 16+ bottles simultaneously on high-speed lines.
Easy Sanitization: Smooth sanitary SS 316 fluid paths allow fast water flushing and CIP sanitization.

⚠️ Considerations & Limitations (Cons)

Free-Flowing Liquids Only: Not suitable for thick gels, heavy creams, or viscous lotions above 500 cPs.
Fill Level vs Strict Volume: If bottles vary in wall thickness, net liquid volume may vary slightly while visual level remains identical.
Requires Recirculation Tank: Closed overflow loop requires clean collection and return tank plumbing.

Type & Range of Gravity & Overflow Machines

On basis of automation & heads

✅ Semi-Automatic 2 & 4 Head Tabletop Level Filler
✅ 6 Head Automatic Inline Gravity Filler
✅ 8 Head Automatic Inline Overflow Filler
✅ 12 Head High-Speed Automatic Level Filler
✅ 16 Head High-Speed Rotary Overflow Bottling Line

On basis of filling method

✅ True Gravity Head Level Filling
✅ Pressure Overflow Level Filling
✅ Vacuum Assist Level Filling

On basis of features

✅ With Automatic Bottle Level Verification & Rejecter
✅ With Overhead Sanitary Buffer Holding Tank
✅ With Overflow Recirculation Pump & Filter
✅ With "No Bottle - No Fill" Safety Gate Logic

Precision-engineered coaxial overflow nozzles achieve uniform liquid line in all bottles
All product contact parts crafted from corrosion-resistant SS 316 / SS 316L
Adjustable fill level spacer collars allow quick modification of target fill height
Closed-loop overflow fluid recycling system prevents splashing and product waste
Optical bottle tracking with automatic pneumatic rejection of improperly positioned bottles
"No Bottle - No Fill" mechanism ensures nozzles only discharge into present containers
Heavy-duty AISI 304 stainless steel framework with protective safety guarding
Supported by over 40 years of precision packaging engineering expertise

Output / Speed	30 to 200+ Bottles Per Minute (BPM) depending on heads and bottle geometry
Container Size Range	30 ml to 2000 ml (Glass, PET, HDPE, Aluminum bottles)
Fill Level Accuracy	± 1 mm height consistency across all bottles
Supported Viscosity	Water-thin to light liquids (0 to 500 cPs)
Number of Nozzles	2, 4, 6, 8, 12, 16 Heads (Linear Indexing & Rotary Formats)
Recirculation System	Sanitary SS 316 return manifold with float-controlled return pump
Material of Construction	AISI 316 / 316L (Contact Parts), AISI 304 (Chassis and Panels)
Control Architecture	PLC with Color Touch Screen HMI & VFD speed synchronization
Power Supply	415V / 3 Phase / 50Hz (Customizable for global electrical standards)
Air Supply	5 to 6 Bar Clean Compressed Air

Format change parts for different bottle heights and neck diameters include:

Coaxial Nozzle Seal Rings & Level Spacers
Infeed / Outfeed Bottle Clamping Star Wheels
Conveyor Guide Rails & Neck Centering Bells
Overflow Return Tube Sets
Sanitary EPDM / Viton Nozzle Gasket Kits
Bottle Infeed Indexing Gate Blocks

Why is an overflow filler preferred for wine and spirits in glass bottles?

Glass bottles frequently have subtle variations in glass thickness and internal volume due to glass molding. A volumetric filler would leave visible differences in liquid height on store shelves, whereas an overflow level filler makes every bottle look identical.

How do you adjust the fill height in the bottle?

The target fill height is easily adjusted by adding or removing precision spacer collars on the nozzle shaft, or via motorized nozzle height adjustment on the HMI.

Does the overflow return line compromise product hygiene?

No. The return line is completely sealed and fabricated from sanitary SS 316 tubing with an inline micron filter, returning clean product back to the sealed holding tank without exposure to environmental dust.

Can the machine handle foaming liquids like window cleaners?

Yes, the overflow principle naturally pulls any surface foam through the return vacuum port at the end of the fill cycle, leaving clear liquid exactly at the target fill line.