Fully-Sealed Scraper Screeners
Fully enclosed screen for fragile materials like granular products in chemical processes.

Product Overview
Fully-Sealed Scraper Screeners are engineered for high-purity screening of fragile, hygroscopic, or chemically sensitive granular materials in industries such as pharmaceuticals, fine chemicals, and food processing. Featuring a fully enclosed design, these screeners eliminate dust emissions and cross-contamination risks while protecting friable particles from degradation during classification. Ideal for processing active pharmaceutical ingredients (APIs), polymer pellets, or catalyst granules, they comply with GB/T standards for safety and performance in demanding industrial settings.Key Features & Benefits
- Hermetic Containment
- Sealed housing with IP66-rated enclosures (per GB/T 4208) prevents airborne particle release and moisture ingress.
- Gas-tight flange connections (optional) for inert gas purging in explosive atmospheres.
- Gentle Material Handling
- Low-speed scrapers (5–15 RPM) with adjustable blade pressure minimize particle breakage.
- Screen deck inclination: 0°–10°, optimized for fragile material retention time.
- Corrosion-Resistant Construction
- Contact surfaces use 304/316L stainless steel (GB/T 3280) or polymer-coated options.
- Welded joints adhere to GB/T 36865-2018 Section 6.2.8 for leak-free integrity.
- Sanitary Design
- CIP/SIP-compatible configurations with radiused corners (R≥3 mm) for easy cleaning.
- Surface roughness: Ra ≤0.8 μm on material-contact areas (per GB/T 1031).
Technical Parameters
Structural Specifications
- Screening Chamber:
- Diameter: 800–2500 mm (customizable).
- Working height: 200–600 mm, with sight glasses for process monitoring.
- Deck Construction:
- Perforated plate thickness: 2–6 mm (apertures 0.5–20 mm).
- Flatness tolerance: ≤1 mm/m² (GB/T 1184-K grade).
- Sealing System:
- Double-lip silicone gaskets (FDA-compliant) with ≤0.1% leakage rate under 5 kPa pressure.
Drive & Scraping Mechanism
- Scraper Assembly:
- Blade material: UHMWPE or PTFE-coated steel.
- Adjustable clearance: 1–5 mm from screen surface.
- Drive Unit:
- Explosion-proof motor (Ex d IIC T4, per GB/T 3836.1) with 0.37–7.5 kW power range.
- Gearbox reduction ratio: 1:50 to 1:150, with torque limiter for overload protection.
Performance Metrics
- Throughput Capacity: 0.5–15 t/h (varies with material density and aperture size).
- Particle Size Range: 0.1–10 mm (fines recovery efficiency ≥98% for >200 μm particles).
- Residual Moisture: ≤0.5% after screening (for hygroscopic granules).
Quality Assurance
- Material Traceability:
- All stainless steel components include Mill Test Certificates per GB/T 3280.
- Non-metallic parts comply with GB 4806.1 for food/medical contact safety.
- Production Controls:
- Dimensional tolerances:
- Chamber cylindricity: ≤1.5 mm total deviation.
- Shaft alignment: ≤0.05 mm/m runout.
- Helium leak testing at 1.5× design pressure (per GB/T 36865-2018 Appendix C).
- Dimensional tolerances:
- Testing Protocols:
- 72-hour continuous run with silica gel granules to validate dust containment (<1 mg/m³ emission).
- Vibration analysis: ≤4.5 mm/s RMS at rated load (ISO 10816-3 Class B).
Applications
- Critical Industries:
- Pharmaceuticals: Screening of APIs, excipients, or tablet granules under GMP conditions.
- Fine Chemicals: Classification of catalyst beads, ion-exchange resins, or polymer powders.
- Food Processing: Sorting dehydrated vegetables, instant coffee granules, or powdered flavors.
- Operational Scenarios:
- Closed-loop recycling of solvent-moistened materials.
- In-line screening of toxic or sensitizing compounds.
Competitive Advantages
- Zero-Emission Guarantee: Patented sealing architecture exceeds GB/T 16292 cleanroom particulate standards.
- Gentle Processing: Combines low shear forces with precise retention time control to preserve granule integrity.
- Regulatory Readiness: Documentation packages support FDA 21 CFR Part 11, EU GMP, and ATEX compliance.
- Modular Upgrades: Optional integration with gloveboxes, nitrogen purging, or explosion venting systems.
Engineered to protect both your product and workforce, our Fully-Sealed Scraper Screeners redefine reliability in critical material handling. Contact us to configure a system tailored to your process’s purity and containment requirements.