Oval gear flow meter YY CL series

volumefor liquidsfor chemicals

Overview
The YUNYI oval/circular gear flowmeter is a positive-displacement (volumetric) meter using precision meshing gears to measure liquid volume per rotation. Fixed cavities formed by the gears deliver a defined volume each revolution, enabling highly repeatable cumulative and instantaneous flow measurement. The design is suited to high-viscosity and high-pressure liquids and to applications requiring trade-level accuracy.

Product Advantages

• High accuracy: Volumetric measurement achieving typical accuracy to ±0.5% R (±0.2% R possible).
• Viscosity-insensitive metering: Maintains accuracy across viscosity ranges; higher viscosity can reduce internal leakage and improve precision.
• No straight-run requirement: Insensitive to upstream velocity profile — flexible installation without long straight piping.
• Wide turndown: Typical turndown ratios of 10:1 or 20:1; some configurations up to 100:1.
• High-pressure capability: Mechanical construction rated up to tens of MPa.
• Multiple outputs: Pulse, 4-20 mA, and digital interfaces for PLC/DCS integration.

Core Application Areas

• Petrochemical: Trade transfer and process control for crude oil, fuel oil, lubricants, resins.
• Food & Beverage: Sanitary quantitative filling and dosing of syrups, edible oils, chocolate, honey.
• Chemical & Coatings: Precise batching of solvents, paints, inks, adhesives.
• Pharmaceutical: Accurate transfer and addition of solutions, glycerin, culture media.
• Calibration & R&D: Reference meters for laboratory and online calibration.

Comparison (Oval/Circular Gear vs Roots/Lobe)

• Rotor design: Oval/circular gear meter — two meshing gears; Roots/Lobe — two or three lobed rotors without contact.
• Fluid contact: Gear meters have gear contact and are lubricated by process fluid; Roots/Lobe rotors operate with clearance and minimal contact.
• Best for: Gear meters — medium to very high viscosity, lubricating liquids; Roots/Lobe — lower-viscosity liquids and gases.
• Pressure drop: Higher for gear meters (increases with viscosity); generally lower for Roots/Lobe.
• Maintenance: Gear meters may need more attention with abrasive fluids; Roots/Lobe typically require less maintenance for clean media.

Typical Media and Limitations

• Ideal: High-viscosity liquids (hydraulic oil, greases, polymer melts, asphalt), lubricating liquids (diesel, biodiesel), chemicals, food-grade viscous products (syrup, molasses, creams).
• Not suitable: Abrasive slurries, non-lubricating fluids (plain water in many cases), or gases. Particulates can cause wear or jamming — install upstream filtration.

Installation & Maintenance

• Installation: Prefer horizontal pipe with gear shaft horizontal; ensure the line is full. Fit coarse strainer/upstream filter (e.g., ~100 mesh). Consider heat tracing for high-viscosity or cold environments. Use bypass or dual meters for very wide flow ranges.
• Maintenance: Regularly clean/replace inlet filter; monitor pressure drop and noise for wear indicators; perform periodic calibration and k-factor checks. Some models allow in-line calibration adjustments.

Integration & Outputs

• Outputs: Mechanical totalizer, pulse (rate/total), 4-20 mA for flow, RS485 for digital communication.
• Protocols: Support for Modbus RTU, HART, Profibus, enabling PLC/DCS/SCADA integration, remote monitoring, diagnostics and batch control.

Certifications & Standards

• Typical certifications: OIML R117, API, 3-A/EHEDG for hygienic versions, ATEX/IECEx for hazardous areas, PED/CRN for pressure equipment (application dependent).

Technical specifications

• Accuracy: Typical ±0.5% R (±0.2% possible)
• Nominal sizes: DN2, DN4, DN6, DN10, DN15, DN25, DN32
• Connections: Threaded, clamp, flange, tri-clamp (sanitary)
• Outputs/communication: Pulse, 4-20 mA, RS485
• Materials: 304 stainless steel, PP, aluminium alloy (others available)
• Range ratio (turndown): Typical 10:1 or 20:1; up to 100:1 in some configs
• Pressure rating: 1.0–40 MPa
• Temperature range: -196 °C to 170 °C
• Suitable media: Particle-free liquids, high-viscosity liquids
• Display: LCD (instantaneous + cumulative flow)