Koehler K86200 Automatic Digital Density Meter (ASTM D1250, D4052, D5002 Compliant)
| Brand | Koehler |
|---|---|
| Origin | USA |
| Model | K86200 |
| Density Range | 0 to 3 g/cm³ |
| Temperature Control Range | 0°C to 90°C |
| Pressure Range | 0 to 10 bar |
| Density Accuracy | ±0.00005 g/cm³ |
| Temperature Accuracy | ±0.03°C |
| Density Repeatability | ±0.00001 g/cm³ |
| Temperature Repeatability | ±0.01°C |
| Resolution | 0.00001 g/cm³ / 0.01°C |
| Minimum Sample Volume | ~1 mL |
| Display | 10.4-inch color touchscreen (800×600 px) |
| Memory | 2 GB internal storage |
| Interfaces | 3× USB, 2× RS232, Ethernet port |
| Power | 85–260 VAC, 48–62 Hz, 150–200 W |
| Dimensions | 440 × 450 × 500 mm |
| Weight | 30 kg |
Overview
The Koehler K86200 Automatic Digital Density Meter is a high-precision oscillating U-tube densimeter engineered for accurate, traceable density and relative density measurements of liquid petroleum products, crude oils, distillates, and related hydrocarbon-based fluids. It operates on the principle of resonant frequency measurement: a precisely machined U-shaped glass tube is filled with sample and excited into oscillation; the resulting natural frequency correlates directly to the mass of the sample and—via temperature-controlled calibration—to its density. This method delivers exceptional stability, minimal operator dependency, and compliance with internationally recognized standard test methods including ASTM D1250 (Petroleum Measurement Tables), ASTM D4052 (Standard Test Method for Density, Relative Density, and API Gravity of Liquids by Digital Density Meter), and ASTM D5002 (Standard Test Method for Density of Crude Oils by Digital Density Analyzer). The instrument maintains thermal equilibrium via Peltier-based temperature control across a wide operational range (0°C to 90°C), ensuring conformity with ISO 12185 and DIN 51757 requirements for certified density analysis in refinery QC, custody transfer, and regulatory reporting environments.
Key Features
- Oscillating U-tube measurement technology with built-in temperature-controlled Peltier system for rapid, stable thermal equilibration
- 10.4-inch high-resolution color touchscreen interface (800 × 600 px) with chemical-resistant surface—designed for routine lab use in corrosive solvent or hydrocarbon-rich environments
- Real-time video magnification (10×) of the U-tube interior, enabling visual verification of bubble-free filling, meniscus position, and sample homogeneity prior to measurement
- Dual-mode operation: supports single-point, continuous, and multi-sample batch analysis with automated sequence programming
- Integrated 2 GB non-volatile memory for secure storage of raw data, calibration logs, user entries, and audit trails—retaining full measurement history without external media dependency
- Comprehensive connectivity suite: three USB ports, two RS232 serial interfaces, and Gigabit Ethernet for seamless integration with LIMS, ELN, and enterprise data systems
- Modular peripheral support—including barcode scanners, external keyboards, mice, and network printers—enabling paperless workflow execution under GLP/GMP conditions
Sample Compatibility & Compliance
The K86200 is validated for use with transparent to slightly hazy liquids exhibiting Newtonian behavior within the specified density range (0–3 g/cm³), including but not limited to: crude oil, gasoline, diesel, jet fuel, lubricating base stocks, biodiesel blends, and refined naphthas. It accommodates samples with viscosity up to 200 mPa·s without compromising accuracy or repeatability. All measurements are traceable to NIST-certified reference standards and fully compliant with ASTM D4052’s procedural rigor—including mandatory temperature stabilization, air calibration, and post-measurement cleaning cycles. The system meets essential regulatory expectations for electronic records and signatures under FDA 21 CFR Part 11 when configured with user access controls, electronic audit trail logging, and data integrity safeguards. Routine verification against certified density standards (e.g., water, benzene, bromobenzene) satisfies ISO/IEC 17025 internal quality assurance protocols.
Software & Data Management
Koehler’s proprietary DensitySuite™ software provides intuitive instrument control, real-time parameter visualization, and structured data export in CSV, XML, and PDF formats. The software embeds configurable calculation engines for API gravity, relative density (d15.6/15.6), and temperature-corrected density per ASTM D1250 tables. Each measurement record includes timestamp, operator ID, ambient conditions, calibration status, U-tube fill image snapshot, and raw oscillation waveform metadata. Audit trail functionality logs all user actions—including method edits, calibration events, and data deletions—with immutable timestamps and operator attribution. Exported datasets retain full traceability for submission to regulatory authorities or third-party auditors. Optional LIMS integration modules support HL7 and ASTM E1384 messaging standards.
Applications
- Refinery process control: real-time density monitoring of crude assay fractions and product streams
- Custody transfer verification for pipeline, marine, and rail transport of hydrocarbons
- Quality assurance of finished fuels (gasoline, diesel, aviation turbine fuel) per ASTM D975 and D1655 specifications
- API gravity determination for crude valuation and fiscal reporting (ASTM D1250)
- Blending optimization in biofuel production facilities using ethanol-diesel or FAME-diesel mixtures
- Research and development of novel synthetic lubricants and specialty solvents requiring high-resolution density profiling
- Regulatory compliance testing for EPA, IMO MARPOL Annex VI, and EU Fuel Quality Directive (2009/30/EC)
FAQ
What ASTM standards does the K86200 support out-of-the-box?
The K86200 is factory-configured and validated for ASTM D1250, D4052, and D5002, with preloaded correction tables and procedural workflows aligned to current editions.
Can the instrument measure viscous or suspended-phase samples?
It is optimized for homogeneous, low-to-moderate viscosity liquids (<200 mPa·s); particulates, emulsions, or highly viscous residues require filtration or dilution prior to analysis to avoid U-tube clogging or damping artifacts.
Is 21 CFR Part 11 compliance enabled by default?
Yes—when deployed with DensitySuite™ v3.2 or later and configured with role-based user accounts, electronic signatures, and audit trail activation, the system satisfies core Part 11 requirements for electronic records and signatures.
How is temperature calibration verified?
The integrated Pt100 sensor is calibrated against NIST-traceable reference thermometers during factory certification; users perform periodic verification using certified thermostats or ice-point baths per ASTM E77.
What maintenance is required between analyses?
Automated rinse-and-dry cycles follow each measurement; recommended quarterly validation includes air/water calibration checks, U-tube inspection under magnified view, and verification of seal integrity and pump performance.
