LEMIS DM-230.1A & DM-230.1B Oscillating U-Tube Digital Densimeter
| Origin | Imported |
|---|---|
| Manufacturer Type | Authorized Distributor |
| Instrument Type | Oscillating U-Tube Densimeter |
| Portability | Portable |
| Sample Phase | Liquid |
| Application Focus | Petroleum Products Density Measurement |
| Density Range | 0.6–2.2 g/cm³ |
| Density Resolution | 0.0001 g/cm³ |
| Temperature Control Range | 15–40 °C (Peltier-regulated) |
| Temperature Accuracy | ±0.03 °C |
| Minimum Sample Volume | 1.5 mL |
| Compliance | ASTM D4052, ISO 12185, IP 365, GB/T 1884 |
Overview
The LEMIS DM-230.1A and DM-230.1B are high-precision, portable oscillating U-tube digital densimeters engineered for rapid, traceable density determination of liquid hydrocarbons and related petroleum products. Based on the fundamental principle of resonant frequency shift—where the natural oscillation period of a precisely machined U-shaped glass tube filled with sample is inversely proportional to its mass—and calibrated against certified reference standards (e.g., air/water or NIST-traceable hydrocarbon standards), these instruments deliver laboratory-grade accuracy in field-deployable form factors. Designed specifically for compliance with international standard test methods including ASTM D4052 (Standard Test Method for Density, Relative Density, and API Gravity of Crude Petroleum and Liquid Petroleum Products by Digital Density Meter), ISO 12185 (Crude petroleum and petroleum products — Determination of density — Oscillating U-tube method), and IP 365, the DM-230 series supports routine QC/QA workflows across upstream sampling, refinery blending control, custody transfer verification, and fuel specification validation.
Key Features
- Integrated Peltier-based temperature regulation with active feedback control ensures stable thermal equilibration across the full 15–40 °C operating range, critical for viscosity-sensitive samples such as diesel, jet fuel, and lubricating oils.
- Dual-model configuration: DM-230.1A optimized for general-purpose petroleum density measurement; DM-230.1B includes enhanced calibration memory and extended API gravity calculation routines aligned with API MPMS Chapter 11.1.
- Compact, battery-operated design (up to 8 hours continuous operation) with IP54-rated enclosure enables use in mobile laboratories, offshore platforms, and tank farm environments without external power or climate control.
- Automated air/water calibration sequence with real-time deviation logging meets GLP documentation requirements and supports audit-ready calibration records.
- High-strength borosilicate U-tube sensor with integrated platinum resistance thermometer (Pt100) ensures long-term dimensional stability and thermal coupling fidelity.
Sample Compatibility & Compliance
The DM-230.1A/B accommodates a broad spectrum of liquid petroleum derivatives—including gasoline, kerosene, naphtha, crude cuts, biodiesel blends (B5–B20), and base oils—provided they are free of suspended solids, entrained gas, or excessive volatility at measurement temperature. Sample introduction is via precision syringe through a sealed inlet port, minimizing operator exposure and evaporation loss. All firmware and calibration protocols adhere to ISO/IEC 17025:2017 technical competence requirements for testing laboratories. Instrument software architecture supports 21 CFR Part 11-compliant user access control, electronic signatures, and immutable audit trails when connected to a compliant networked environment.
Software & Data Management
The embedded firmware provides on-device data storage for up to 1,000 measurements with timestamp, temperature, density, API gravity, and user ID metadata. Optional PC connectivity via USB-C enables export of CSV-formatted reports compatible with LIMS integration. The companion LEMIS Densidata Suite (v3.2+) supports advanced statistical analysis (e.g., moving average trend monitoring, repeatability assessment per ASTM D4052 Annex A1), certificate generation per ISO/IEC 17025, and automated report templating aligned with internal QA templates or regulatory submission formats. All calibration and verification logs are digitally signed and time-stamped to satisfy GMP/GLP record retention mandates.
Applications
- Field verification of crude oil density prior to pipeline injection or marine loading
- In-line density trending during distillation column optimization
- Blending tank certification for reformulated gasoline (RFG) and ultra-low-sulfur diesel (ULSD)
- API gravity reporting for customs valuation and tax classification (e.g., 26 U.S.C. § 4081)
- Quality release testing of aviation turbine fuel (Jet A/A-1) per ASTM D1655 Annex A3
- Monitoring density drift in stored biofuels to detect phase separation or oxidation onset
FAQ
What standards does the DM-230.1A/B comply with for petroleum density measurement?
ASTM D4052, ISO 12185, IP 365, and GB/T 1884 are fully supported through built-in calculation engines and certified calibration protocols.
Can the instrument measure samples with high vapor pressure, such as light naphthas?
Yes—when used with the optional pressurized sample adapter kit (LEMIS P-SA-230), the system maintains sample integrity at vapor pressures up to 150 kPa absolute.
Is temperature calibration traceable to national metrology institutes?
The integrated Pt100 sensor is factory-calibrated against NIST-traceable dry-block standards; users may perform field verification using certified thermostats per ISO 17025 Clause 6.5.
How is data integrity ensured during offline field use?
All measurements include cryptographic hash signatures, internal clock synchronization, and write-once memory allocation to prevent post-acquisition modification.
Does the device support automatic API gravity conversion?
Yes—both models compute API gravity per ASTM D1250 and ISO 91-1 using the measured density and temperature, with selectable reference temperature (15.6 °C or 60 °F).
