Marimex ViscoScope® VA-300 Online Viscometer
| Brand | Marimex |
|---|---|
| Origin | Germany |
| Model | VA-300 |
| Sensor Materials | 1.4571 / 1.4404 (316Ti/316L), optional Hastelloy C22 or duplex 2205 |
| Temperature Range | −40 °C to +450 °C |
| Pressure Range | Vacuum to 450 bar |
| Measurement Range | 0.1–2,500,000 mPa·s (model-dependent) |
| Repeatability | ±0.3% or ±1 digit (VA-300L/M) |
| IP Rating | IP65 |
| Integrated Temperature Sensor | Pt100 |
| Optional ATEX Certification | II 1/2G Ex ia IIC T6–T3 Ga/Gb |
Overview
The Marimex ViscoScope® VA-300 Online Viscometer is a robust, in-line rotational viscometer engineered for continuous, real-time viscosity monitoring in demanding industrial process environments. It operates on the principle of torsional resonant vibration—measuring the damping effect of process fluid on a precisely oscillating stainless-steel sensor element. Unlike capillary or rotational cup-based systems, this design eliminates moving parts, bearings, or seals, delivering intrinsic mechanical reliability and zero maintenance requirements over extended service life. The sensor’s resonance frequency shift correlates directly with dynamic viscosity and density, enabling high-fidelity measurement under turbulent, pulsating, or low-flow conditions where traditional methods fail. Its all-welded construction and compatibility with CIP (Clean-in-Place) and SIP (Sterilize-in-Place) protocols make it suitable for regulated biopharmaceutical, food, and fine chemical applications requiring full traceability and hygiene compliance.
Key Features
- Hermetically sealed, all-welded sensor housing fabricated from ASTM A240 UNS S31603 (316L) or UNS S31635 (316Ti) stainless steel—optionally available in UNS N06022 (Hastelloy C22) or UNS S32205 (duplex 2205) for aggressive media.
- Wide operational envelope: −40 °C to +450 °C process temperature and vacuum to 450 bar pressure—validated per EN 13480 and ASME B31.3.
- Integrated Pt100 Class A temperature sensor (IEC 60751) co-located with the active sensing element, enabling simultaneous, spatially correlated viscosity and temperature measurement without external compensation drift.
- No moving parts, no bearings, no seals—eliminating wear mechanisms and leakage paths; certified for SIL 2 functional safety per IEC 61508 when configured with appropriate safety controllers.
- Multiple model variants (VA-300L, VA-300M, VA-300H, VA-300X) optimized for distinct viscosity ranges and signal-to-noise requirements across laminar, transitional, and highly viscous regimes.
- ATEX/IECEx-certified explosion-proof variants available for Zone 0/1 hazardous areas (II 1/2G Ex ia IIC T6–T3 Ga/Gb), compliant with Directive 2014/34/EU.
Sample Compatibility & Compliance
The VA-300 is validated for homogeneous liquids, suspensions, emulsions, and non-Newtonian fluids exhibiting shear-thinning or thixotropic behavior—provided particulate content remains below 15 wt% and particle size is <100 µm to avoid abrasion or clogging. It complies with key industry standards including ISO 2555 (viscosity determination), ASTM D2196 (non-Newtonian fluids), and USP <911> (rheological characterization of pharmaceutical formulations). In hygienic applications, the sensor meets 3-A Sanitary Standards 74-01 and EHEDG Doc. 8.2 for surface finish (Ra ≤ 0.8 µm), crevice-free geometry, and drainability. All wetted materials are REACH-compliant and FDA 21 CFR §177.2600 approved for food contact. For GxP environments, the system supports audit trails, electronic signatures, and 21 CFR Part 11–compliant data integrity protocols when integrated with validated SCADA or DCS platforms.
Software & Data Management
The VA-300 outputs analog (4–20 mA HART) and digital (RS-485 Modbus RTU, optional Profibus DP or Foundation Fieldbus) signals. Configuration, calibration, and diagnostics are performed via Marimex’s PC-based ViscoLink™ software, which provides real-time trend visualization, automatic temperature compensation algorithms, and configurable alarm thresholds (high/low viscosity, temperature deviation, sensor fault). Raw data—including resonance frequency, phase angle, damping coefficient, and Pt100 resistance—is timestamped and exportable in CSV or XML format. When deployed in validated manufacturing systems, ViscoLink™ supports IQ/OQ documentation templates aligned with Annex 11 and GAMP 5 guidelines. Firmware updates follow change control procedures compliant with ISO 13485 and ICH Q9 principles.
Applications
- Petrochemical refining: Real-time monitoring of lube oil blending, polymer melt viscosity in extrusion lines, and heavy fuel oil conditioning prior to combustion.
- Pharmaceutical manufacturing: In-situ viscosity control during buffer preparation, monoclonal antibody formulation, and sterile filtration validation—ensuring batch consistency and reducing hold-time variability.
- Food & beverage processing: Continuous measurement of tomato paste, chocolate mass, dairy concentrates, and plant-based alternatives during thermal concentration and homogenization.
- Pulp & paper: Robust black liquor viscosity monitoring at digester discharge and evaporation stages—even under high solids (>35 wt%) and elevated temperature (>120 °C).
- Paints & coatings: Closed-loop control of solvent evaporation kinetics during inline mixing and dispersion, maintaining target rheology for spray, roll, or dip coating processes.
FAQ
How does the VA-300 handle non-Newtonian fluids?
It measures apparent viscosity at the native shear rate imposed by the resonant oscillation (typically 10–100 s⁻¹), providing repeatable process-relevant values—not absolute zero-shear viscosity. For yield stress estimation, optional multi-frequency sweep mode is available on VA-300H/X models.
Can the sensor be calibrated in situ without removal?
Yes—zero-point calibration is performed dry (in air or nitrogen), while span calibration uses traceable reference oils injected via a dedicated calibration port; both procedures are fully documented in ViscoLink™ and support ALCOA+ data integrity principles.
Is the VA-300 compatible with sanitary Tri-Clamp connections and CIP cycles?
All sanitary variants feature 3-A compliant Tri-Clamp end fittings, electropolished surfaces (Ra ≤ 0.4 µm), and full compatibility with NaOH/HNO₃-based CIP solutions at 85 °C and SIP steam at 135 °C for ≥30 minutes.
What is the minimum required flow velocity for accurate measurement?
The VA-300 functions reliably at velocities as low as 0.05 m/s in pipe installations and is insensitive to flow profile—making it suitable for recirculation loops, static tanks with gentle agitation, and low-Reynolds-number processes.
Does the system support predictive maintenance analytics?
Yes—ViscoLink™ logs long-term resonance amplitude decay and temperature hysteresis trends, enabling early detection of fouling onset or material fatigue well before performance degradation exceeds specification limits.
