Doebritz CIRV Series Cement Industry Rotary Valve, Heavy-Duty Airlock, Cast Iron / ATEX Certified / <1.5% Air Leakage

Product Summary

Doebritz CIRV Series rotary valves deliver high-efficiency airlock sealing for cement pneumatic conveying, silo discharge, and dust collection systems. Engineered to handle fine cement powder, raw meal, and clinker dust with capacities from 0.5 to 60 m³/hr and differential pressure up to 1.5 bar. ATEX certified (Zone 22/21) option available. Precision-machined rotors achieve air leakage rate <1.5% – lowering energy costs and boosting throughput.

Why Source Doebritz Valves

• Ultra-Low Air Leakage: <1.5% across 1.5 bar differential pressure – reduces compressed air waste and operational costs.
• ATEX Certified Explosion-Proof Configuration: Full ATEX Zone 22/21 compliance with anti-static rotor tips and flame-path housing.
• CNC Precision Rotor Engineering: Each rotor is dynamically balanced on Mazak 5-axis CNC machining centers with <0.05mm tip-to-housing clearance.
• Global OEM Supply with Fast Lead Times: Standard models 15-20 days; custom flange patterns, shaft extensions, and abrasion-resistant liners available.
• Superior Wear Life in Abrasive Cement Dust: Hard-chrome plated rotor and replaceable tungsten carbide tip scrapers as option for extreme duty.

Housing & Rotor Engineering

The Doebritz CIRV housing is cast from GGG 40 ductile iron (or SS304/316L) with integral machined mounting pads for outboard bearings – this design isolates the bearing housing from the material zone, preventing cement infiltration. The rotor features an open-end 8-vane or 10-vane configuration with machined swept-back pockets to minimize material grinding. All rotors are CNC profile-ground and individually dry-clearance tested before assembly. Optional abrasion-resistant stellite hardfacing on vane tips extends service life in high-silica cement applications.

Technical Specifications

The following standard ranges apply to the Doebritz CIRV platform. Custom engineering (flange dimensions, shaft material, polished internal bores) can be quoted for OEM integration or plant retrofit.

Specification	Detail
Body Material	GGG 40 Ductile Iron (standard) / SS304 / SS316L (option)
Rotor Design	8-vane open rotor, CNC-ground, tip clearance <0.10mm
Inlet/Outlet Size Range	DN150 to DN500 (6” to 20”)
Capacity (max)	60 m³/hr @ 20 rpm bulk density 1.2 t/m³
Max Differential Pressure	1.5 bar(g) standard / 2.5 bar(g) with reinforced rotor
Max Operating Temp.	-20°C to +120°C standard / -20°C to +250°C (HT option)
ATEX Certification	Zone 22 (dust) / Zone 21 (gas) – Optional
Bearing Type	Outboard-mounted, sealed spherical roller bearings
Shaft Seal	PTFE lip + air purge connection (standard) or mechanical seal (option)

Heavy-Duty Application Scenarios

Pneumatic Conveying Systems

Installed downstream of cement mill cyclones or silo discharge cones, the CIRV provides controlled, air-locked material feed into dense or dilute phase conveying lines. Works with Blower pressures up to 1.5 bar(g) without bridging or flushing.

Silo Discharging & Truck Loading

Mount the Doebritz valve directly under cement storage silos, fly ash bins, or lime hoppers. Our heavy-duty cast housing and replaceable wear sleeves withstand abrasive flow at high cycle counts (>1,000,000 cycles without performance drop).

Dust Filter Collectors & Baghouses

As a baghouse rotary airlock, the CIRV reliably discharges fine dust under negative pressure or positive venting. ATEX-certified models include flame arrestor and temperature monitoring port (optional up to 200°C continuous).

Frequently Asked Questions

What are the standard delivery times for Doebritz CIRV valves?

Standard cast iron models with DN150 to DN400 flanges: 15-20 working days EXW Doebritz plant. Stainless steel or ATEX-certified valves: 4-5 weeks. Urgent OEM projects can be expedited – contact our project desk.

Can you manufacture non-standard flange drilling patterns or custom inlet/outlet dimensions?

Yes. Doebritz supports full OEM engineering. Provide your connection dimensions (DIN/ANSI/JIS or custom bolt circle) and we will CNC-machine the housing flanges without tooling charges for volumes ≥10 pcs. Minimum order quantity for full custom casting: 25 pcs.

Is this valve suitable for high-temperature cement dust above 150°C?

Yes. The Doebritz CIRV-HT variant uses high-temperature graphite-filled PTFE rotor tips and extended bearing standoffs. Maximum continuous operating temperature: 250°C (cast iron housing) or 350°C with SS310 housing and air-cooled bearing pedestal. ATEX compliance maintained up to 200°C.

Do you provide ATEX certification and documentation for Zone 21/22?

Absolutely. Every Doebritz CIRV-ATEX model is certified by an EC-Type Examination Certificate (Notified Body). You receive full technical file, Declaration of Conformity, and individual serial-numbered nameplate. Available for both gas and dust explosive atmospheres.

What is the guaranteed air leakage rate, and how do you verify it?

Doebritz guarantees ≤1.5% leakage of theoretical volumetric displacement at 1.0 bar differential pressure. Each valve undergoes a pressurized air leakage test before shipping – test report included. For high-efficiency pneumatic conveying, we can supply low-leakage rotors with ≤0.8% leakage (add 15% to base valve price).