Automatic Volumetric Cup Granule Packaging Machine Guide: High-Speed Dosing and Cost-Effective Sachet Sealing Solutions

In dry food processing, agricultural packaging, and chemical manufacturing, granular materials such as refined sugar, sea salt, monosodium glutamate (MSG), seasoning pellets, seeds, dry beans, and plastic beads represent some of the highest-volume portioned packaging categories worldwide. For packaging facilities seeking high throughput with straightforward mechanical maintenance, volumetric cup vertical form-fill-seal (VFFS) systems offer an efficient, field-proven solution.

Compared to complex multihead combination weighers or sensitive electronic load cells, rotary volumetric cup metering delivers dependable portioning speed, exceptional mechanical robustness, and low capital investment. In this technical guide, Huapai Machinery explains the mechanical working principle, cup volume adjustment methods, film sealing synchronization, and key project considerations for volumetric cup granule packaging machines.

Why Choose Volumetric Cup Dosing for Granule Packaging?

Volumetric cup dosing systems measure granular products based on physical cavity volume rather than dynamic gravitational weighing. For free-flowing dry materials with uniform bulk density, this mechanical method provides notable operational advantages:

• High Packaging Speed: Continuous rotating cup turntables can deliver 30 to 70 discharges per minute, smoothly synchronized with vertical continuous bag forming mechanisms.
• Mechanical Simplicity & Durability: With no electronic weighing load cells or fragile flexures, volumetric cup machines withstand plant vibration and continuous multi-shift operation with minimal downtime.
• Cost-Effective Capital & Maintenance: Simplified mechanical linkages reduce both initial equipment acquisition costs and ongoing spare parts expenditures.
• Rapid Product Changeover: Telescoping cup designs allow operators to fine-tune portion weights quickly via a single centralized adjustment screw without replacing parts.

Watch the Factory Video: Continuous Volumetric Cup Granule Packaging Operation

The video below demonstrates Huapai Machinery's automatic volumetric cup granule packaging machine during live factory testing. The rotating cup disc continuously fills, scrapes, and discharges measured granule charges directly into the vertical forming collar, producing clean, tightly sealed back-seal sachets:

Step-by-Step Operating Principle of Volumetric Cup VFFS Machines

The volumetric cup packaging process operates in continuous mechanical synchronization across six interconnected stages:

1. Hopper Infeed & Cavity Filling: Granular material flows by gravity from the upper stainless steel storage hopper into the rotating cup disc chamber, completely filling each open measuring cup.
2. Level Scraping (Uniform Volume): A stationary leveling scraper sweeps across the top of the rotating cups, removing excess granules and ensuring a flush, uniform fill volume in every pocket.
3. Bottom Gate Discharge: As the filled cup rotates over the discharge chute opening, the trapdoor bottom opens, releasing the measured granular charge directly into the vertical bag former tube.
4. Roll Film Collar Forming: Flexible packaging laminate is pulled over the collar-style forming shoulder, converting flat film into a continuous vertical cylinder around the drop tube.
5. Longitudinal Back Sealing: Heated vertical seal rollers or pneumatic sealing bars continuously fuse the overlapping film edges to form a hermetic back seam.
6. Cross Sealing & Guillotine Cut: Heated horizontal sealing jaws close synchronously to form the top seal of the filled sachet and bottom seal of the next pouch, with an integrated knife severing the completed sachet.

Key Design Features for High Accuracy and Clean Sealing

To ensure consistent pouch weights and prevent granule dust from contaminating heat seal areas, Huapai Machinery integrates several critical engineering features into our volumetric packaging machines:

• Telescoping Cup Height Adjustment: Precision threaded height adjusters allow continuous fine-tuning of cup depth, accommodating density variations across different product batches.
• Mirror-Polished SUS304 Contact Parts: All material-contact hoppers, cups, scrapers, and discharge tubes are made of food-grade stainless steel with polished seams to eliminate granule buildup.
• Zero-Gap Scraper Assembly: Specially engineered scraper blades ensure clean cut-offs without crushing fragile pellets or creating airborne dust.
• Photoelectric Eye-Mark Sensor: High-sensitivity optical sensors read printed film registration marks to ensure exact pattern centering on every sachet.

Suitable Granular Products and Incompatible Materials

Understanding product physical characteristics is essential when deciding between volumetric cup dosing and alternative weighing systems:

• Ideal Applications (High Accuracy):
  • Free-flowing food granules: White sugar, refined salt, MSG, chicken bouillon granules, instant coffee granules.
  • Agricultural grains & seeds: Millet, sesame seeds, mustard seeds, vegetable seeds, dry yeast.
  • Industrial & chemical pellets: Desiccant beads, plastic resin pellets, fertilizer prills, detergent beads.
• Not Recommended for Volumetric Cups:
  • Sticky, oily, or hygroscopic powders that bridge inside cavities.
  • Irregular large-piece snacks (e.g., potato chips or whole walnuts) where piece-to-piece void ratios vary drastically (multihead weighers recommended).

Technical Specifications Overview for Volumetric Cup Packing Machines

Note: Packaging speed and portion accuracy depend on material bulk density uniformity, target fill volume, and film sealing characteristics.

Project Parameters to Specify Before Ordering a Machine

To receive an accurate machine sizing and tooling proposal from Huapai Machinery's engineering team, preparing the following information will streamline equipment selection:

1. Material Details: Product name, particle size distribution, moisture content, and bulk density (grams per cubic centimeter).
2. Target Filling Grammage: Minimum, standard, and maximum target portion weight per sachet.
3. Finished Pouch Dimensions: Desired pouch width and length, or maximum film roll width.
4. Preferred Bag Sealing Style: Center back seal (pillow sachet), three-side seal, or stick pack.
5. Required Hourly Output: Production capacity targets to coordinate with upstream mixing or storage bins.
6. Optional Accessories: Ribbon date coder, hot stamping printer, nitrogen flushing device, or finished sachet discharge conveyor.