Granular Fertilizer Packing Machine

Equipment Introduction

The granular fertilizer packaging machine, also known as a granular quantitative packaging scale, is a core piece of equipment for packaging finished granules in organic fertilizer and compound fertilizer production lines. Specifically designed for 3-8mm fertilizer granules, it employs a fast/slow dual-gate gravity feeding system combined with net weight weighing. Unlike powder screw packaging machines, it prevents granule crushing, ensures smooth feeding, and provides accurate measurement.

(I) Mainstream Model Classification

1. Single-hopper gravity granular packaging machine: Standard for small factories, single-person operation, suitable for 10-50kg woven bags, high cost-effectiveness;

2. Double-hopper high-speed granular packaging machine: Dual weighing units operate alternately, increasing capacity by 50%, suitable for large fertilizer bases;

3. Fully automatic bag-loading granular packaging line: Robotic arms automatically open, clamp, convey, sew, and palletize bags, enabling unmanned production;

4. Small bag vertical granular packaging machine: 1-10kg water-soluble fertilizer and foliar fertilizer small packaging, for supermarket retail use.

(II) Core Industry Advantages

1. Extremely Low Particle Breakage: Gravity-fed feeding, no screw extrusion, particle breakage rate ≤1%, ensuring the appearance of the fertilizer product;

2. Precise and Compliant Metering: Two-stage segmented feeding, single bag weight error ±0.2%~±0.5%, conforming to national standards for agricultural input metering;

3. Corrosion and Anti-caking: All materials in contact with the material are made of 304 stainless steel, and the hopper is equipped with vibration-damping technology to prevent moisture-absorbing particles from bridging and clogging the material;

4. Low Dust Design: Annular seal at the bag opening + negative pressure dust removal, no fertilizer dust in the workshop, meeting environmental protection acceptance standards;

5. Wide Bag Type Compatibility: PP woven bags, kraft valve bags, and inner film composite bags are all compatible; one-click formula switching for 1–50kg capacity;

6. Simple Operation and Maintenance: No easily clogged screw structure, short cleaning and replacement time for parts.

Structural composition

Although there are various models of granule packaging machines, their core structural logic is consistent and is mainly composed of the following systems:

1. Storage and feeding system

Hopper/silo: used to temporarily store materials to be packaged, usually equipped with an arch breaking device or vibrator to prevent materials from bridging.

Feeding mechanism: According to the characteristics of the material, the gravity flow, screw conveying, vibration feeding or belt conveying method is selected to evenly feed the material into the metering unit.

2. Metering system

Weighing sensor + weighing hopper: Using an electronic weighing module (accuracy usually ±0.1%–±0.3%), the controller controls the feeding process according to the preset program based on the sensor weight signal, and stops when the set weight is reached.

Volumetric metering: metering through a measuring cup or turntable, suitable for regular particles with stable density.

3. Bag making and filling system (vertical packaging machine)

Former: The film roll is stretched and guided and then folded into a U-shaped tube.

Longitudinal sealing roller: heat seals the longitudinal edge of the film into a cylindrical bag.

Horizontal sealing roller: Completes bag bottom sealing (bag making) and bag top sealing (sealing), and at the same time, the cutter cuts at the sealing point to form an independent packaging bag.

4. Bag clamping and unloading system (open/ton bag packaging machine)

Bag clamping cylinder/air bag: Automatically clamps woven bags or kraft paper bags to prevent dust from escaping during blanking.

Discharging gate: automatically opens after the weighing reaches the standard, and the materials fall into the bag by gravity.

5. Sealing and conveying system

Heat sealing device: suitable for plastic film bags, with adjustable temperature (usually 120–180°C).

Bag sewing machine: suitable for woven bags and kraft paper bags to complete seam sealing.

Conveyor belt: conveys the finished bags to the palletizing or storage station.

6. Control system

PLC+touch screen: realizes functions such as parameter setting, recipe storage, fault alarm, output statistics, etc., and supports Chinese and English interfaces.

Working Principle

This system employs a dual-gate segmented gravity feeding, independent net weight weighing, and a closed-loop dust removal filling process:

1. Qualified granules after cooling and screening are fed into the top buffer silo via a bucket elevator. A vibrating motor continuously vibrates to prevent moisture-absorbing granules from bridging and failing to discharge.

2. A manual/robotic arm seals the bag opening with the discharge sealing skirt, and a cylinder automatically clamps the bag opening, simultaneously activating negative pressure dust removal.

3. PLC controls the coarse gate to rapidly discharge material. When 85% of the set weight is reached, the coarse gate closes, and only the fine gate provides a small amount of material replenishment. Sensors collect weight data in real time to compensate for the inertial impulse of the falling material.

4. Once the standard weight is reached, both the coarse and fine gates close, the bottom discharge door of the weighing hopper opens, and the granules fall into the packaging bag.

5. After unloading, the discharge door resets, the bag-clamping cylinder releases, and the bag filled with granules falls onto the conveyor belt, transporting it to the sealing station.

6. A small amount of dust generated during filling is recovered by the dust collector, and fine particles are returned to the silo, resulting in zero raw material loss.

Applications in Production Lines

1. Fertilizer Granule Production Line

After granulation, drying, cooling, and screening, the granule packaging machine serves as the finished product output terminal: Qualified granules are conveyed to the packaging machine's hopper via a belt conveyor; The packaging machine weighs granules in 25 kg/50 kg increments, automatically clamps, fills, and sews the bags; Finished bags are conveyed to the palletizing area or directly loaded onto trucks.

The entire line can achieve full automation of the "crushing → mixing → granulation → drying → screening → packaging" process.

2. Food Production Line

After raw material mixing or baking, the granule packaging machine completes the small bag packaging (e.g., 5 g–1 kg), which can be directly connected to pillow packaging machines or cartoning machines to form a complete food packaging production line.

3. Chemical and Feed Production Lines

Typically, open-bag or ton bag packaging machines are used. These lines have large processing capacities and high dust control requirements, necessitating a dust removal system and explosion-proof motors.

Target Customers:

1. Large-scale production plants of organic fertilizer, compound fertilizer, slow-release granular fertilizer, and water-soluble fertilizer;

2. Large-scale livestock and poultry breeding groups with their own manure granulation processing workshops;

3. Agricultural input wholesalers, fertilizer repackaging and storage stores, and flower nutrient fertilizer repackaging stores;

4. Municipal sludge and kitchen waste resource-based fertilizer production enterprises;

5. Fertilizer complete equipment and fully automated palletizing line supporting service providers;

6. Overseas fertilizer and organic fertilizer processing plants' foreign trade equipment procurement customers.

Summary of Equipment's Comprehensive Technical Features:

1. Strong granule protection: Pure gravity feeding with no compression results in extremely low finished product breakage, increasing fertilizer market value.

2. Stable and compliant metering: Dual-gate segmented weighing ensures errors meet national agricultural input metering standards, preventing market complaints.

3. Anti-clogging design suitable for high-moisture granules: Vibration-based arch-breaking hopper solves the problem of moisture absorption and bridging in organic fertilizers.

4. Environmentally friendly and dust-free: Fully enclosed negative pressure dust removal at the bag opening; unified recycling of powdery fine particles ensures environmental compliance in the workshop.

5. Optional automation levels: Low-cost semi-automatic and fully automatic unmanned lines cater to fertilizer companies of different sizes.

6. Corrosion-resistant and durable: All materials in contact with the material are made of 304 stainless steel, resistant to long-term acid and alkali corrosion from urea and potassium fertilizers.

7. Compatible with all bag types: One-button switching across the entire 1–50kg range, accommodating both retail small bags and wholesale large bags.