Fixed Speed Rotary Valve, Doebritz Rotary Airlock Feeder, Heavy-Duty Cast Iron / ATEX Certified

Product Summary

Doebritz Fixed Speed Rotary Valve is engineered for continuous, high-efficiency bulk material discharge in demanding industrial environments. With capacities up to 200 m³/h for powders, granules, and flakes, this rotary airlock feeder achieves ultra-low air leakage (<0.02 m³/min at 10 psi). Available with Cast Iron or Stainless Steel 304 housing and ATEX certified explosion-proof rotor, it ensures stable pressure sealing and safe operation in explosive dust atmospheres. The fixed-speed drive configuration provides consistent metering without complex VFD control, making it the go-to choice for silo discharge, dust collectors, and pneumatic conveying systems.

Why Source Doebritz Fixed Speed Rotary Valves

• Ultra-Low Air Leakage: Precision machined rotor-to-housing clearance down to 0.08mm minimizes blow-by, preserving system pressure and reducing energy waste.
• Superior Wear Resistance: Hardened cast iron housing (450 HB) and replaceable stainless steel end plates extend service life by 3-5x compared to standard rotary valves.
• ATEX Certified Safe: All Doebritz Fixed Speed Rotary Valves meet ATEX Zone 22 (II 3D c T125°C) standards, with optional Zone 21/20 configurations for explosive dust environments.
• Global OEM Supply Ready: Backed by ISO 9001:2015 and full material traceability, Doebritz provides direct OEM integration, custom flange drilling (ANSI/DIN/JIS), and 5-year spare parts availability.
• Fast Lead Time: Standard cast iron models ship within 10 working days. Emergency 48-hour expedited service available for critical plant shutdowns.

Housing & Rotor Engineering

The Doebritz Fixed Speed Rotary Valve housing is precision cast from GG25 gray iron or CF8 stainless steel, featuring integrally cast inspection ports for easy maintenance. The drop-through design enables free gravity flow of materials, reducing bridging and blockages. The rotor employs a heavy-duty 8-vane closed open rotor geometry, CNC-machined to achieve consistent tip clearances. Outboard bearings with triple labyrinth seals protect the bearing housing from dust ingress, while the fixed speed gearmotor (selectable 15, 25, 40 rpm) provides constant volumetric discharge. For abrasive or sticky materials, we offer optional chrome-plated rotor coating and polished internal surfaces. All Doebritz valves undergo 100% air leakage testing and dye penetrant inspection of castings before shipping.

Technical Specifications

The following table outlines key technical parameters for Doebritz Fixed Speed Rotary Valves. Custom configurations (including special alloys, FDA compliant seals, and cryogenic service) are available upon request. Strict quality control ensures each unit complies with your required operating temperature, pressure differential, and material characteristics. Contact our technical team for sizing assistance.

Specification	Detail
Body Material	Cast Iron GG25 / Stainless Steel 304 (316L optional)
Rotor Design	8-Vane Open Rotor, CNC machined clearance 0.08-0.12mm
Drive Speed	Fixed 15, 25, or 40 rpm (others on request)
Capacity	Up to 200 m³/h (depending on rpm and material density)
Max Pressure Diff.	1.5 bar (22 psi) standard, up to 3.5 bar available
Max Temperature	Standard +80°C / HT version +250°C / Ceramic +400°C
ATEX Certification	Zone 22 (II 3D c T125°C); Zone 20/21 optional
Connection	ANSI #150, DIN PN10, or JIS 10K (custom flanges available)

Heavy-Duty Application Scenarios

Pneumatic Conveying Systems

Doebritz Fixed Speed Rotary Valves act as pressure-tight airlocks feeding dilute or dense phase conveyors. The minimal air leakage ensures stable line pressure, reducing compressor load by up to 12% compared to conventional valves. Ideal for cement, fly ash, plastic pellets, and starch.

Silo Discharging with Bridge Breaking

For cohesive powders (e.g., carbon black, lime, food ingredients), the Doebritz valve’s large inlet flange and anti-bridge rotor pockets promote reliable mass flow. Optional agitator or vented rotor designs eliminate rat holing and degrade.

Dust Filter Collectors & Baghouses

Mounted under filters or cyclones, these valves discharge collected dust without leaking system vacuum. ATEX certified options safely operate in wood, grain, metal dust environments. Heavy-duty shafts survive high torque start-ups under full dust loads.

Chemical & Pharmaceutical Powder Dosing

With optional stainless steel 316L construction, electropolished finish, and sanitary seals, Doebritz valves provide contaminant-free metering for API powders, lactose, and pigments. Fixed speed ensures repeatable batch dosing without drift.

Frequently Asked Questions

1. What is the minimum order quantity (MOQ) for Doebritz Fixed Speed Rotary Valves?

Our standard MOQ is 1 unit, supporting both project-based single orders and large OEM contracts. Volume pricing is available for orders of 10+ units.

2. Can you supply custom flanges or non-standard inlet/outlet sizes?

Yes. Doebritz provides free technical drawings approval for custom flange drilling (ANSI #150, DIN PN10, JIS 10K) and square-to-round adapters. Minimum custom order charge applies only if CAD modifications exceed 2 hours.

3. Are Doebritz Fixed Speed Rotary Valves ATEX certified for Zone 20?

Standard valves are ATEX Zone 22 certified (II 3D c T125°C). For Zone 20 or 21 (continuous dust presence), we offer high-protection versions with cast aluminum bodies, grounding continuity, and temperature limiting devices. Please specify your zone requirement when ordering.

4. What is the maximum operating temperature for these valves?

Standard nitrile seals allow up to 80°C. For high-temperature applications (up to 250°C), choose the HT package with Viton seals, expanded clearance rotor, and air-cooled bearing pedestals. For up to 400°C, we provide carbon graphite rotor tips and ceramic-coated housing.

5. What are typical lead times and warranty coverage?

Standard cast iron valves: 10 working days (ex-works). Stainless steel or custom orders: 3-4 weeks. Doebritz offers a 2-year warranty against manufacturing defects and a 10-year spare parts commitment after purchase.