A single-deck vibro sifter uses a circular vibrating screen (Ø300–2,000 mm, 25–5,000 µm rating) energised by a dual-motor eccentric drive (900–3,600 RPM) to classify feed into two fractions under-screen (pass) and over-screen (reject). Processing 20–10,000 kg/h, it achieves separation efficiency greater than 95% and is the standard GMP sieving device for pharmaceutical powder quality control, de-lumping, and oversize particle rejection before tablet compression.
Feed material is delivered centrally onto the vibrating screen surface; three-dimensional gyratory motion horizontal orbit combined with vertical vibration stratifies particles by size. Fines migrate through the screen aperture while oversize particles spiral outward to the periphery and discharge. Ball trays below the screen surface prevent blinding by continually impacting the underside of the mesh. Screen inclination and vibration amplitude/frequency are adjusted to balance throughput against separation sharpness. CIP-in-place design with spray ball cleans screen and housing in 20–30 minutes without screen removal.
Challenges
Screen Blinding with Fine Cohesive Powder
Electrostatic and cohesive powders blind fine mesh screens within 10–30 minutes throughput collapses.
Low Throughput at Fine Screen Rating (<100 µm)
Fine apertures limit flow-per-unit-area; require larger diameter or ultrasonic assistance to maintain rate.
Screen Frame Fatigue at High Vibration Amplitude
High-amplitude operation fatigues screen frame welds at corners and mounting points mesh failure.
Dust Generation at Feed Point
Open powder loading onto vibrating screen generates significant ambient dust OEB risk.
Screen Mesh Damage from Tramp Metal
Metal fragments in feed puncture woven-wire mesh contaminate passed fraction with metal.
Solutions
- Ultrasonic Screen Tensioning (36 kHz): Ultrasonic vibration prevents particle adhesion enables sustained throughput at <75 µm without blinding.
- Ball Tray (Anti-Blinding) Below Screen: Rubber or PTFE balls impact screen underside every vibration cycle prevents mesh blinding continuously.
- Reinforced Wire Mesh (200× Wire Thickness at Frame Border): Heavy-gauge wire construction at frame borders prevents fatigue cracking at corners.
- Enclosed Feed Inlet with Dust Collar: Flexible dust collar at feed inlet prevents ambient powder release during loading.
- Magnetic Grid on Feed Inlet (12,000 Gauss): Rare-earth magnetic bars intercept ferrous tramp metal before screen contact protects mesh integrity.
Applications
- Pharmaceutical: API powder sieving, granule QC classification, tablet blend de-lumping, oversize rejection before compression.
- Food & Beverage: Flour sieving, sugar grading, spice classification, instant beverage powder quality control.
- Chemical: Pigment classification, catalyst particle grading, specialty powder QC sieving.
- Cosmetics: Talc and mineral powder classification, finished cosmetic powder quality control sieving.
- Nutraceuticals: Supplement powder QC, protein powder classification, vitamin premix oversize rejection.
Models & Capacities
| Type 1Â Single-Deck Vibro Sifter: Models & Capacities | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Model | Scale | Throughput [kg/h] | Screen Ø [mm] | Screen Rating [µm] | Decks | Vibration Motor [kW] | Vibration Freq. [RPM] | L × W × H [mm] | Weight [kg] |
| VS-D1-300 | Lab | 20–100 | Ø300 | 25–5,000 | 1 | 0.12–0.18 | 900–3,600 | 500×500×800 | 35 |
| VS-D1-450 | Lab/Pilot | 50–300 | Ø450 | 25–5,000 | 1 | 0.18–0.37 | 900–3,600 | 650×650×900 | 55 |
| VS-D1-600 | Pilot | 100–600 | Ø600 | 25–5,000 | 1 | 0.37–0.55 | 900–3,600 | 800×800×1,000 | 90 |
| VS-D1-900 | Production | 300–1,500 | Ø900 | 25–5,000 | 1 | 0.55–0.75 | 900–3,600 | 1,100×1,100×1,100 | 160 |
| VS-D1-1200 | Production | 600–3,000 | Ø1,200 | 25–5,000 | 1 | 0.75–1.1 | 900–3,600 | 1,400×1,400×1,200 | 280 |
| VS-D1-1500 | Production | 1,000–5,000 | Ø1,500 | 25–5,000 | 1 | 1.1–1.5 | 900–3,600 | 1,700×1,700×1,300 | 420 |
| VS-D1-2000 | Large Prod | 2,000–10,000 | Ø2,000 | 50–5,000 | 1 | 1.5–2.2 | 900–3,600 | 2,200×2,200×1,400 | 680 |