Brookfield DVNXLV Cone-Plate Rheometer

Overview

The Brookfield DVNXLV Cone-Plate Rheometer is a precision torque-transduction instrument engineered for absolute viscosity and controlled-shear-rate rheological characterization of low-volume liquid samples. It operates on the fundamental principle of cone-and-plate geometry, where a precisely angled rotating cone shears a thin, uniform film of sample against a stationary plate—establishing a well-defined, linear shear rate profile across the gap. This geometry eliminates wall slip and edge effects common in coaxial cylinder systems, enabling true first-order Newtonian and non-Newtonian flow curve analysis (e.g., yield stress, power-law index, thixotropy) with metrological confidence. Designed for R&D laboratories in pharmaceuticals, coatings, cosmetics, and biomedical research, the DVNXLV delivers traceable, SI-traceable mPa·s (cP) values without empirical calibration curves—leveraging geometric constants (cone angle, radius), rotational speed (RPM), and measured torque to compute shear stress and shear rate directly per ISO 3219:2022.

Key Features

• Electronic gap setting system: Eliminates manual feeler-gauge dependency; achieves reproducible 0.001 mm gap resolution via calibrated micrometer ring and real-time position feedback.
• Low-volume operation: Supports quantitative rheology with only 0.5–2.0 mL sample volume—critical for precious biological fluids, catalyst slurries, or noble-metal-containing pastes.
• Thermally integrated sample cup: Double-walled stainless-steel cup with inlet/outlet ports compatible with external recirculating chillers or heating baths (0–100 °C).
• Full-range torque transduction: High-stability beryllium-copper torsion spring sensor with ±1.0% full-scale accuracy and ±0.2% repeatability per ASTM D2196 Annex A2.
• Auto-zero and auto-range functions: Compensates for thermal drift and dynamically selects optimal torque range based on rotor/speed combination—ensuring maximal signal-to-noise ratio across all measurements.
• Modular cone rotor compatibility: Interchangeable stainless-steel cones (CPA-40Z to CPA-52Z) calibrated as matched sets with the sample cup—no recalibration required when swapping rotors.
• Integrated 7-inch capacitive touchscreen: Local control with real-time graphing, method storage, and export-ready CSV/TXT data output.

Sample Compatibility & Compliance

The DVNXLV accommodates Newtonian liquids, pseudoplastic suspensions, yield-stress gels, and weakly structured emulsions—provided they remain homogeneous under shear and do not exhibit significant particle sedimentation during measurement. All wetted surfaces are electropolished 316 stainless steel, resistant to organic solvents, aqueous buffers, and mild acids/bases. The instrument supports regulatory compliance workflows: audit trails, user access levels, electronic signatures, and raw-data integrity align with FDA 21 CFR Part 11 requirements when used with Brookfield’s optional Rheo3000 software. It meets ISO 3219:2022 (rotational viscometers), ASTM D2196 (non-Newtonian fluids), and USP (rheological evaluation of semisolid dosage forms). Calibration certificates are NIST-traceable and include uncertainty budgets per ISO/IEC 17025.

Software & Data Management

While standalone operation is fully functional via the built-in touchscreen, the DVNXLV integrates seamlessly with Brookfield’s Rheo3000 PC software (Windows 10/11). Rheo3000 enables advanced protocol scripting (ramp, oscillatory, time-sweep), real-time G′/G″ calculation (via optional strain-controlled mode add-on), statistical batch reporting, and automated compliance reporting for GLP/GMP environments. All raw torque vs. time and RPM vs. time datasets are stored with metadata (operator ID, timestamp, environmental temperature, rotor ID, gap value), supporting full data lineage. Export formats include CSV, Excel, PDF reports, and XML for LIMS integration.

Applications

• Pharmaceutical formulation: Viscosity profiling of topical gels, ophthalmic solutions, and injectable suspensions under physiologically relevant shear rates (0.1–1000 s⁻¹).
• Electronics manufacturing: Rheological validation of conductive inks, solder pastes, and dielectric coatings prior to screen printing or dispensing.
• Food science: Yield stress quantification of yogurts, sauces, and plant-based dairy alternatives to predict mouthfeel and stability.
• Academic rheology: Fundamental studies of polymer melts, colloidal dispersions, and wormlike micellar systems requiring precise shear history control.
• Quality control: Rapid pass/fail testing of incoming raw materials (e.g., resins, surfactants) against pre-established flow curve specifications.

FAQ

What is the minimum sample volume required for accurate measurement?
0.5 mL is sufficient when using the CPA-40Z or CPA-51Z cone rotors—verified per ISO 3219 Annex B for geometric validity.
Can the DVNXLV perform oscillatory measurements?
No—the DVNXLV is a steady-shear (rotational) rheometer. Oscillatory capability requires the DVNext CP+ or DVNext HR series with motor-in-head architecture.
Is temperature control internal or external?
Temperature is externally regulated via the double-walled sample cup’s fluid ports; users must supply a certified recirculating bath meeting ±0.1 °C stability.
How often does the system require calibration verification?
Annual verification with Brookfield-certified standard oils (e.g., NIST-traceable silicone standards) is recommended; daily zero-check is performed automatically at startup.
Are cleaning accessories included?
Luer-lock cleaning adapters and ultrasonic-compatible sample cup holders are available as optional accessories—not shipped standard.