ZiQi NDJ-8S Digital Rotational Viscometer

Overview

The ZiQi NDJ-8S Digital Rotational Viscometer is a precision-engineered benchtop instrument designed for reliable, repeatable measurement of dynamic viscosity in Newtonian and mildly non-Newtonian fluids across industrial QC labs, R&D facilities, and academic teaching environments. Based on the Couette principle—where torque required to rotate a spindle at controlled angular velocity within a fluid sample is measured—the NDJ-8S delivers quantitative rheological data under steady-shear conditions. Its direct-drive stepper motor eliminates gear backlash and slippage, ensuring traceable rotational speed fidelity across all eight discrete speed settings (0.3–60 rpm). The instrument operates without external water baths or temperature control units, making it suitable for ambient-temperature screening of paints, adhesives, pharmaceutical suspensions, food emulsions, lubricants, and polymer solutions where moderate shear sensitivity and broad dynamic range are critical.

Key Features

• Direct-coupled stepper motor drive system—no reduction gears—guarantees accurate, stable rotational speed and long-term mechanical integrity.
• Backlit blue LCD display with simultaneous readout of current viscosity value, selected spindle/speed combination, and real-time maximum measurable viscosity at that setting.
• Auto-range alert: Audible tone triggers when torque exceeds spindle capacity, preventing sensor overload and preserving calibration stability.
• Full-scale linear calibration correction applied digitally across the entire 1–2×10⁶ mPa·s range, supporting traceability to internal reference standards.
• Universal AC power input (100–240 V, 50/60 Hz) with integrated EMI filtering—optimized for use in electrically noisy production or shared lab environments.
• Compact footprint (275 × 230 × 475 mm) and rigid aluminum alloy housing ensure vibration resistance and operational stability on standard lab benches.

Sample Compatibility & Compliance

The NDJ-8S accommodates standard LV-type spindles (L1–L4), enabling viscosity characterization of low-to-medium viscosity liquids (e.g., solvents, syrups, coatings) as well as high-viscosity pastes and gels when using lower speeds and larger-diameter spindles. Optional L0 spindle extends low-shear capability for ultra-high-viscosity materials such as uncured silicone elastomers or bituminous binders. While the NDJ-8S itself does not include built-in temperature control or regulatory-grade audit trails, its measurement methodology aligns with foundational principles referenced in ASTM D2196, ISO 2555, and GB/T 2794—making it appropriate for preliminary screening, in-process verification, and internal method development prior to GLP/GMP validation. Users deploying this viscometer in regulated environments should implement supplementary documentation controls (e.g., manual logbooks, calibrated thermometers, and periodic inter-laboratory verification) to meet ISO/IEC 17025 or FDA 21 CFR Part 11 expectations.

Software & Data Management

The NDJ-8S operates as a standalone instrument with no proprietary software dependency. All measurements are displayed and retained locally on the LCD screen during active operation. For data capture and trending, users may integrate the viscometer into existing laboratory informatics systems via optional RS-232 or USB-to-serial adapters (not included). When connected, ASCII-formatted output—including timestamp (if externally synchronized), spindle ID, speed, viscosity value, and unit—is transmitted at user-defined intervals. This interface supports import into Excel, LabArchives, or LIMS platforms for batch reporting, statistical process control (SPC), and long-term stability monitoring. No embedded database, user roles, or electronic signature functionality is provided—consistent with its role as a dedicated physical property test tool rather than a fully validated analytical platform.

Applications

• Quality control of water-based and solvent-based coatings: verifying batch-to-batch consistency of flow behavior before spray application or dip coating.
• Pharmaceutical formulation support: assessing suspension stability and pourability of oral liquids and topical gels under low-shear conditions.
• Food product development: characterizing shear-thinning profiles of dressings, sauces, and dairy alternatives during routine production checks.
• Adhesive and sealant manufacturing: confirming open time, sag resistance, and pumpability of uncured formulations.
• Polymer solution evaluation: monitoring molecular weight trends via relative viscosity in dilute organic solvent systems.
• Academic instruction: demonstrating fundamental viscometry concepts including shear rate dependence, Newtonian vs. pseudoplastic response, and spindle selection criteria.

FAQ

What spindle configurations are supported by the NDJ-8S?

The instrument ships with four standard LV spindles (L1–L4); L0 is available as an optional accessory for extended high-viscosity measurement.
Is temperature control integrated into the NDJ-8S?

No—this is an ambient-temperature-only instrument. External thermostated sample holders or jacketed vessels must be used for temperature-dependent studies.
Can the NDJ-8S comply with FDA 21 CFR Part 11 requirements?

Not natively. It lacks electronic signatures, audit trails, and secure user authentication. Validation for regulated use requires procedural controls and third-party data capture solutions.
How often should calibration verification be performed?

We recommend daily verification using certified silicone oil standards (e.g., Brookfield NIST-traceable oils) before critical measurements, with full recalibration annually or after mechanical impact.
Does the NDJ-8S support continuous data logging?

Only when connected to a host PC via serial interface; onboard memory is limited to real-time display only.