Hengping NDJ-8S LCD Digital Rotational Viscometer
| Brand | Hengping |
|---|---|
| Model | NDJ-8S |
| Type | Rotational Viscometer |
| Viscosity Range | 2–1×10⁶ mPa·s |
| Spindle Set | Standard #1–#4 spindles (optional #0 spindle for 0.1–10 mPa·s) |
| Speed Settings | 0.3, 0.6, 1.5, 3, 6, 12, 30, 60 rpm |
| Accuracy | ±1% for Newtonian liquids |
| Display | Backlit LCD with dual-language (English/Chinese) interface |
| Communication | RS-232 serial port |
| Optional Accessories | PT100 temperature sensor, thermal printer, PC software suite |
| Power Supply | AC 220 V ±10%, 50 Hz ±10% |
| Operating Environment | 5–35 °C, ≤80% RH |
| Dimensions (W×D×H) | 380×320×390 mm |
| Net Weight | 4.5 kg |
Overview
The Hengping NDJ-8S LCD Digital Rotational Viscometer is a precision-engineered instrument designed for reliable and repeatable viscosity measurement of both Newtonian and non-Newtonian fluids under controlled laboratory or quality control conditions. Based on the Couette flow principle—where torque exerted on a rotating spindle immersed in a sample is proportional to the fluid’s dynamic viscosity—the NDJ-8S delivers stable, traceable measurements across an extended range of 2 to 1×10⁶ mPa·s. Its microprocessor-controlled architecture ensures consistent rotational speed regulation, real-time torque sensing, and automatic stabilization detection. The instrument complies with fundamental metrological requirements outlined in ISO 2555 and ASTM D2196 for rotational viscometry, making it suitable for routine QC testing where reproducibility and documentation integrity are essential.
Key Features
- High-contrast backlit LCD display with English/Chinese bilingual interface for intuitive operation in international lab environments
- Eight precisely regulated rotational speeds (0.3–60 rpm), enabling optimal shear rate selection across diverse sample rheologies
- Standard set of four geometrically calibrated spindles (#1–#4); optional #0 spindle extends low-viscosity capability down to 0.1 mPa·s
- Integrated RS-232 serial interface supporting bidirectional communication with Windows-based PCs for automated data logging and report generation
- All-aluminum housing with EMI-shielded head assembly, enhancing long-term mechanical stability and electromagnetic compatibility
- Auto-stop function triggered upon viscosity stabilization—reducing operator dependency and minimizing measurement drift
- Compliant power supply design (220 V ±10%, 50 Hz ±10%) with built-in overvoltage and thermal protection circuits
Sample Compatibility & Compliance
The NDJ-8S is validated for use with homogeneous, single-phase liquids—including oils, polymer melts, paints, coatings, food emulsions, pharmaceutical suspensions, and surfactant solutions—provided they do not contain abrasive particles or exhibit extreme thixotropy that compromises spindle immersion consistency. While not certified for GMP-regulated production environments out-of-the-box, its RS-232 output supports integration into validated systems when paired with compliant PC software featuring audit trail, electronic signature, and 21 CFR Part 11 readiness. Temperature monitoring via optional PT100 probe enables viscosity correction per ISO 3219 and ASTM D445 protocols. The device meets CE marking requirements for electrical safety (IEC 61010-1) and electromagnetic immunity (IEC 61326-1).
Software & Data Management
The included Windows-compatible software provides real-time graphing of viscosity vs. time or shear rate, customizable test templates, and export functionality to CSV, Excel, and PDF formats. Each recorded session captures timestamp, spindle ID, rotational speed, measured torque, calculated viscosity, ambient temperature (if sensor connected), and operator ID. Audit logs record all parameter changes, calibration events, and user logins—supporting GLP-compliant documentation workflows. Data files are digitally signed and tamper-evident, aligning with internal QA policies requiring full traceability from raw measurement to final report.
Applications
- Quality assurance of industrial lubricants and transformer oils per ASTM D445
- Routine viscosity checks of paint formulations during R&D and batch release
- Stability assessment of cosmetic gels and hair conditioners under varying shear profiles
- Process consistency monitoring of edible oils, syrups, and dairy-based sauces
- Evaluation of polymer solution concentration and molecular weight trends
- Teaching laboratories demonstrating Newtonian/non-Newtonian behavior using standardized reference oils
FAQ
What spindle configurations are supported by the NDJ-8S?
The instrument ships with four standard spindles (#1–#4) optimized for mid-to-high viscosity ranges; the optional #0 spindle enables accurate measurement of low-viscosity fluids such as solvents or thin aqueous solutions.
Can the NDJ-8S operate under temperature-controlled conditions?
Yes—when connected to an external bath circulator (e.g., DCX-130B or CH1006 series) and equipped with the optional PT100 temperature sensor, the system supports viscosity measurement at stabilized temperatures between 5 °C and 95 °C.
Is the instrument compatible with modern LIMS or ELN platforms?
Via RS-232, raw data streams can be parsed by third-party middleware; however, native HL7 or ASTM E1384 integration requires custom API development or intermediary data acquisition software.
How is calibration verified on this model?
Calibration is performed using NIST-traceable silicone oil standards; users may execute verification checks at multiple speeds and spindles to confirm linearity and repeatability per ISO/IEC 17025 guidance.
Does the NDJ-8S support continuous rotation mode for time-dependent rheological analysis?
No—it operates in discrete measurement mode only; for creep recovery, oscillatory, or controlled-stress experiments, a dedicated rheometer (e.g., rotational or oscillatory type) is required.
