A high-shear plough shear mixer with choppers integrates 2–4 wall-mounted chopper assemblies (1,500–3,000 RPM, tip speed 25–40 m/s) operating simultaneously with the main plough blades (60–250 RPM) — providing two independent shear zones within a single vessel. The choppers break primary agglomerates and disperse liquid binder at a localised high-shear rate while the plough blades maintain bulk three-dimensional circulation. Processing 10–3,000 kg, it achieves finer granule D90 (0.1–1.0 mm) and tighter PSD than standard configuration.
Challenges
Chopper Pin Breakage from Dense Agglomerate Impact
High-density mineral or sugar agglomerates fracture chopper pins — metal contamination risk.
Over-Milling at High Chopper Speed Late in Granulation Cycle
Extended chopper operation after binder incorporation over-mills granules — fines >15%.
Chopper Housing CIP Dead-Zone at Pin Root
Binder residue accumulates at chopper pin-to-disc junction — validated CIP coverage required.
Noise Above 90 dB(A) from Dual High-Speed Rotating Assemblies
Combined plough and chopper operation at maximum speed requires hearing protection and acoustic enclosure.
Synchronisation of Plough and Chopper Speed Profiles per Recipe
Incorrect chopper activation timing relative to binder addition creates inconsistent granule batches.
Solutions
- Grade 316L SS Chopper Pins with Stellite Tip (Fracture-Resistant): Stellite-tipped pins resist dense agglomerate impact — service life 3–5× standard SS 316L.
- Recipe-Based Chopper Speed Programme (VFD per Chopper, ±1 RPM): PLC recipe controls each chopper independently — speed reduces to zero at endpoint hold phase.
- Self-Draining Chopper Housing (Tangential Flush Port + CIP Lance): Dedicated CIP lance enters chopper bore and flushes pin root zone — validated residue removal.
- Acoustic Enclosure Around Chopper Motor Assemblies (−15 dB Reduction): Foam-lined SS enclosure on each chopper motor reduces external noise to <78 dB(A).
- PLC Dual-Torque Endpoint (Plough + Chopper Combined Power Trend): Both motor current traces combined to a single endpoint parameter — tighter batch-to-batch control.
Applications
- Pharmaceutical: Fine granule wet granulation for immediate-release, MR tablets; HPAPI granulation with fine PSD control.
- Nutraceuticals: Fine supplement granule production requiring narrow PSD for capsule dosing uniformity.
- Chemical: Fine specialty chemical granule wet agglomeration; catalyst support fine granule production.
- Food & Beverage: Fine instant food and beverage granule; uniform granule size for controlled dissolution rate.
- Cosmetics: Ultra-fine compact powder granule; mineral cosmetic fine particle wet granulation.
Models & Capacities
1A — Standard Horizontal Plough Shear Wet Granulator (PSW) — 10 L Lab to 3,000 L Large Production — Batch Size 2–1,800 kg — Granule D90 0.3–2.5 mm | ||||||||
Model | Scale | Bowl Vol [L] | Batch Size [kg] | Blade Motor [kW] | Blade RPM | Tip Speed [m/s] | Granule D90 [mm] | Â |
PSW-010 | Lab | 10 | 2 – 6 | 1.5 – 3 | 60–250 VFD | 2 – 6 | 0.3 – 2.5 |  |
PSW-030 | Pilot | 30 | 8 – 18 | 4 – 7.5 | 60–250 VFD | 2 – 7 | 0.3 – 2.5 |  |
PSW-100 | Pilot/Prod | 100 | 30 – 60 | 11 – 18.5 | 60–250 VFD | 3 – 7 | 0.3 – 2.5 |  |
PSW-300 | Production | 300 | 90 – 180 | 30 – 37 | 60–200 VFD | 3 – 8 | 0.3 – 2.5 |  |
PSW-600 | Production | 600 | 180 – 360 | 55 – 75 | 60–200 VFD | 3 – 8 | 0.3 – 2.5 |  |
PSW-1000 | Large Prod | 1,000 | 300 – 600 | 90 – 132 | 60–180 VFD | 3 – 8 | 0.3 – 2.5 |  |
PSW-3000 | Large Prod | 3,000 | 900 – 1,800 | 220 – 280 | 60–150 VFD | 3 – 8 | 0.3 – 2.5 |  |