In floating fish feed production lines, vibrating screens play a crucial role as the “quality guardian” — they are mainly used for precise classification, powder removal, and separation of broken or oversized particles of cooled finished products. This ensures uniform particle size, stable floatability, and good palatability of the feed, while also recycling fine powder to reduce losses and protect downstream equipment. For feed manufacturers, a high-performance vibrating screen is not just an auxiliary device, but a key guarantee for improving product quality and production efficiency.
Key Installation Position
To better understand its function, let’s first review the typical process of floating fish feed production:
Raw Material Crushing → Mixing → Extrusion → Drying → Oil Spraying/Seasoning → Cooling → Vibrating Screen → Finished Product Packaging
The vibrating screen is installed after cooling and before packaging, serving as the final quality check before the finished products leave the factory. This position is critical because it directly filters out unqualified products and ensures that only high-quality feed enters the packaging link.
Core Functions of Vibrating Screens
1. Precise Particle Size Classification (Ensuring Uniform Specifications)
Vibrating screens are equipped with 1–3 layers of screens, which can separate feed into standard particle sizes according to customer needs, such as 1.5–2.0mm (for fry), 2–4mm (for juvenile fish), and 4–6mm (for adult fish). By removing oversized particles (uncut or stuck together) and overly fine powder (broken or powdered), the finished feed has a consistent particle size, good palatability, and ensures uniform feeding of fish.
2. Powder Removal and Recycling (Cost Reduction & Quality Improvement)
One of the important functions of vibrating screens is to separate and collect fine powder and broken materials, which are then sent back to the mixer for re-granulation. This not only reduces waste but also improves the finished product rate. At the same time, removing surface floating powder prevents dust caking, poor water stability, and water turbidity after packaging — problems that directly affect the feed’s marketability and user experience.
3. Protecting Floatability and Water Stability (Core Indicators)
Floating fish feed relies on its porous structure to maintain floatability and water stability. The vibrating screen adopts a three-dimensional vibration and low-damage design, which ensures that the particle integrity rate is ≥98%. This design does not damage the porous structure of the extruded feed, allowing the feed to float for more than 20 hours without collapsing. In addition, uniform particles absorb water consistently, avoiding problems such as “sinking first then floating” or “rapid disintegration” in water.
4. Removing Impurities and Defective Products (Quality Control)
Vibrating screens effectively remove impurities such as charred particles, hard lumps, hair, and metal debris (after pre-magnetic separation) from the feed. This not only improves the purity of the product but also enhances the brand reputation, as high-purity feed is more favored by aquaculture farmers.
5. Ensuring Continuous Production (Efficiency Improvement)
With automatic discharge and continuous operation, vibrating screens reduce manual sorting and labor intensity, matching the rhythm of production lines with a capacity of 500–5000kg per hour. Moreover, they prevent fine powder from entering the packaging machine, which would cause mold jamming and material blockage, thereby reducing downtime for cleaning and improving overall production efficiency.
Advantages of Vibrating Screens for Floating Fish Feed
- Anti-clogging Screen: Equipped with a bouncing ball screen cleaning system and a sealed structure, it is suitable for high-humidity (12–14%), oily, and sticky materials, ensuring no screen clogging and continuous operation.
- Low Damage Rate: Adjustable amplitude (5–8mm) and flexible vibration trajectory result in a particle breakage rate of <2%, effectively protecting the porous structure of the extruded feed.
- 304 Stainless Steel Material: The parts in contact with food are corrosion-resistant and easy to clean, complying with hygiene standards for aquatic feed.
Common Configurations
- Layers: 1–2 layers (2 layers are commonly used: the upper layer removes oversized particles, the lower layer removes powder, and the middle layer is the finished product).
- Screen Aperture: Customized according to the finished product specifications (e.g., 2.0mm/4.0mm).
- Power: 0.75–2.2kW, with low noise and low energy consumption.
Conclusion
In summary, the vibrating screen is an indispensable key equipment in the floating fish feed production line. It ensures that the feed is uniform, clean, intact, and stable, directly determining the appearance of the finished product and the effect of aquaculture. For feed manufacturers looking to improve product quality and market competitiveness, choosing a suitable vibrating screen is a wise investment.